AutoCAD Instruction Manual

AUTOCAD

CAD-Computer Aided Design, also known as Computer Aided Drafting, is the use of computer software and systems to design and create 2D and 3D virtual models of goods and products for the purposes of testing. It is also sometimes refered to as Computer assisted drafting. AutoCAD- is a CAD software application for 2D and 3D design and drawing developed and sold by Autodesk, initially released in late 1982.

AUTOCAD HISTORY AND TIMELINE

1. AUTOCAD V 1.0 DECEMBER 1982

2. AUTOCAD V1.2 APRIL 1983 3. AUTOCAD V1.3 AUGUST 1983 4. AUTOCAD V1.4

OCTOBER 1983 5. AUTOCAD V2.0

OCTOBER 1984 6. AUTOCAD V2.1 MAY 1985 7. AUTOCAD V2.5 JUNE 1986 8. AUTOCAD V2.6

APRIL 1987 9. AUTOCAD VR9

SEPTEMBER 1987 10. AUTOCAD R10

OCTOBER 1988 11. AUTOCAD R11

OCTOBER 1990 12. AUTOCAD R12 JUNE 1992 13. AUTOCAD R13

OCTOBER 1994 14. AUTOCAD R14 FEBRUARY 1997 15. AUTOCAD R2000 MARCH 1998 16. AUTOCAD R2000i JULY 2000 17. AUTOCAD R2002 JULY 2001 18. AUTOCAD R2004 MARCH 2003 19. AUTOCAD R2005 MARCH 2004 20. AUTOCAD R2006 MARCH 2005 21. AUTOCAD R2007 MARCH 2006

22. AUTOCAD R2008 MARCH 2007 23. AUTOCAD R2009

JUNE 2008 24. AUTOCAD 2010

MARCH 2009 FIELDS OF USE

THE ARCHITECHURAL, ENGINEERING, AND CONSTRUCTION (AEC) INDUSTRY

Architechural Architechural engineering Interior design Interior Architechture Building engineering Civil engineering and insfrastructure Construction Roads and highways Railroads and Tunnels Water supply and hydraulic Engineering Storm Drain, Wastewater and sewer system Mapping and Surveying Chemical Plant Design Factory Layout Heating, Ventilation and air-conditioning

(HVAC) MECHANICAL (MCAD) ENGINEERING

Automotive- vehicles Aerospace Consumer Goods Machinery Shipbuilding Bio chemical system Electronic design automation (EDA) Electronic and Electrical (ECAD) Digital circuit design Electrical engineering Manufacturing process planning Industrial Design Software application Apparel and Textile CAD

AUTOCAD WINDOW

1. Title Bar - This will show you what program you are running and what the current filename is.

2. Pull-down menus - These are the standard pull-down menus through which you can access almost all commands.

3/8/2015 POWER SKILLS TECHNICAL CENTER www.powerskillsonline.com

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AUTOCAD 3. Main toolbar - This has most of the standard

Windows icons, as well as the most common AutoCAD commands.

4. Property toolbar - This toolbar gives a way to quickly modify an object's properties, such as layer and linetype.

5. Floating toolbar - This is a toolbar that can be moved around the screen, or 'docked' as the main toolbar is.

6. Drawing space - This is where you draw. You have an almost infinite area to draw and this is just a 'section' of the entire space.

7. Scrollbars - These work like in other windows programs. You can also use the PAN command to move around your drawing.

8. WCS Icon - This is here to show you which direction positive X and positive Y go. The W means you're in the World Co-ordinate System. (It can be changed to a User Co-ordinate System.)

9. Status Bar Tray Icons - These icons give you updates on items like reference files program updates and print status.

10. Command line - When you type a command, you will see it here. AutoCAD uses this space to 'prompt' you for information. It will give you a lot of information and tell you where you are in the command. Watch this line while learning.

11. Status bar - This allows to see and change different modes of drawing such as Ortho, Osnaps, Grid, Otrack, etc.

THE X,Y COORDINATE SYSTEM

Everything that you draw in AutoCAD is exact. It will be more accurate than you will ever need it to be. All objects drawn on the screen are placed there based on a simple X,Y co-ordinate system. In AutoCAD this is known as the World Co-ordinate System (WCS). You must understand this to know how to put things where you want them.

In order to work effectively with AutoCAD, you have to work with this system. Until you are comfortable and familiar with it.

Here is how it works:

AutoCAD uses points to determine where an object is located. There is an origin where it begins counting from. This point is (0,0). Every object is located in relation to the origin. If you were to draw a line straight out to the right from the origin, this would be considered the positive X-axis. If you were to draw a line straight up, this would be the positive Y-axis. The picture at the left shows a point located at (2,3). This means that the point is 2 units over in the X-axis and 3 units up in the Y-axis. When you are working with points, X always comes first. The other point shown is (-3,1). This means that the point is 3 units in the negative X-axis (left) and 1 unit in the positive Y-axis (up).

Most of the time you will not have an indication of where the origin is. You may need to draw a line from the endpoint of an existing line. To do this you use relative or polar coordinates.

Entering Points in AutoCAD

You can enter points directly on the command line using three different systems. The one you use will depend on which is more applicable for the situation. The first assignment will get you used to this. The three systems are as follows:

ABSOLUTE CO-ORDINATES - Using this method, you enter the points as they relate to the origin of the WCS. To enter a point just enter in the exact point as X,Y.

RELATIVE CO-ORDINATES - This allows you to enter points in relation to the first point you have entered. After you've entered one point, the next would be entered as @X,Y. This means that AutoCAD will draw a line from the first point to another point X units over and Y units up relative to the previous point.

POLAR CO-ORDINATES - You would use this system if you know that you want to draw a line a certain distance at a particular angle. You would enter this as @D<A. In this case, D is the distance and A is the angle. Example: @10<90 will draw a line 10 units straight up from the first point.

The three ways of entering co-ordinates shown above are the ONLY way AutoCAD accepts input.


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http://we-r-here.com/cad/tutorials/level_1/1-1.htm%23relative%23relative

AUTOCAD First decide which style you need to use, and then enter as shown. Remember that X is always before Y (alphabetical). Don't forget the '@' symbol when you are entering relative points. Any typing error or omission will give you results you don't want. If you make a mistake and need to see what you typed, press F2 to bring up the text screen and check your typing. (press F2 to get back to your drawing.)

STARTING A DRAWING

There are three main methods that you can use to create a new drawing. (The first option, Open a Drawing, is not available from the NEW command. To open an existing drawing, use OPEN.) Choose one of the buttons at the top of the dialog box

1. Start from Scratch

Starts an empty drawing using default imperial or metric settings. AutoCAD stores this setting in the MEASUREINIT system variable. You can change the measurement system for a given drawing by using the MEASUREMENT system variable. To start a new drawing based on a customized template, see Use a Template.

Imperial

Starts a new drawing based on the Imperial measurement system. The default drawing boundary (the drawing limits) is 12 × 9 inches.

Metric

Starts a new drawing based on the metric measurement system. The default drawing boundary (the drawing limits) is 429 × 297 millimeters.

2. Use a Template

Starts a drawing based on a drawing template file. Template drawings store all the settings for a drawing and may also include predefined layers, dimension styles, and views. Template drawings are distinguished from other drawing files by the .dwt file extension. They are normally kept in the template directory.

Several template drawings are included with AutoCAD. You can make additional template drawings by changing the extensions of drawing file names to

.dwt. See Use a Template File to Start a Drawing in the User's Guide.

Select a Template

Lists all DWT files that currently exist in the drawing template file location, which is specified in the Options dialog box. Choose a file to use as a starting point for your new drawing. A preview image of the selected file is displayed to the right.

Browse

Displays the Select Template dialog box (a standard file selection dialog box) where you can access template files that are not available in the Select a Template list.

3. Use a Wizard

Sets up a drawing using a step-by-step guide. You can choose from two wizards: Quick Setup and Advanced Setup.

Quick Setup

Displays the Quick Setup wizard, in which you can specify the units and area for your new drawing. The Quick Setup wizard also changes settings, such as text height and snap spacing, to an appropriate scale.

Advanced Setup

Displays the Advanced Setup wizard, in which you can specify the units, angle, angle measure, angle direction, and area for your new drawing. The Quick Setup wizard also changes settings, such as text height and snap spacing, to an appropriate scale

SAVING A FILE

Saves the drawing under the current file name or a specified name

Keyboard SAVE or CTRL+S

Menubar > File > Save as

QSAVE- The QSAVE command is equivalent to clicking Save on the File menu.


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AUTOCAD If the drawing is named, AutoCAD saves the drawing

using the file format specified on the Open and Save tab of the Options dialog box and does not request a file name. If the drawing is unnamed, AutoCAD displays the Save Drawing As dialog box (see SAVEAS) and saves the drawing with the file name and format you specify.

If the drawing is read-only, use the SAVEAS command to save the changed file under a different name

SAVING FILE AS

JPG FORMAT JPGOUT

BMP FORMAT BMPOUT

TIFF FORMATT TIFOUT

PNG FORMAT PNGOUT

GIF FORMAT GIFOUT

GRID- Pattern of dots displayed on screen to guide you. (F7)

LIMITS- Drawing limits is used to define the extent of the grid display and to toggle limits mode which can be used to define the extent of your drawing.

Reset Model space limits: Example you want to change the limits to 20,20.

command: limits (enter)

Specify lower left corner or [ON/OFF] <0.000,0.000> (enter)

Specify upper right corner <12.0000,9.0000> 20,20 (enter)

LINE- Line are probably the most simple command of AutoCAD.a line can be drawn between any two points picked within area.

Draw toolbar

Pull down menu Draw > Line

Keyboard LINE or L

ERASE- The command erases(deletes) any selected object(s) from the drawing.

Modify toolbar Pull down menu Modify > Erase Keyboard ERASE or E

UNDO- Use to cancel actions you’ve made.

Standard toolbar

Keyboard UNDO, U or Ctrl + Z

ZOOM- Increases or decreases the apparent size of object in the current viewport.

Zoom All Z(enter) A(enter)

Zoom Extents Z(enter)E(enter)

Zoom Window Z(enter)W(enter)

Zoom Center Z(enter) C(enter)

Zoom Dynamic Z(enter) D(enter)

Zoom Previous Z(enter) P(enter)

Zoom Scale Z(enter) S(enter)


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AUTOCAD DIRECT DISTANCE ENTRY

Direct distance entry is one of those AutoCAD features that is often overlooked. This is rather unfortunate because it can be extremely useful and an amazing time-saver. Basically, direct distance entry enables you to draw an object, such as a line, by pointing in a particular direction with the cursor and entering a distance at the command line.

How does it work?

Say, for example, you wanted to draw a horizontal line with a length of 30 drawing units. Start the Line

command, Draw Line from the pull-down menu or from the Draw toolbar. When prompted, to specify the first point for the line, pick a point somewhere on the left side of the drawing area.

You now need to constrain the line to the horizontal. You can do this using Polar Tracking . Use the POLAR button on the status bar to turn on Polar Tracking. Usually, Polar Tracking is on by default, so you may not need to do this.

Now, move your cursor to the right of the first pick point. If you are within a few degrees of the horizontal, you should see something similar to the illustration above. Hold your cursor in this position and simply enter 30 at the keyboard. When you hit the Return key, a line segment is drawn, 30 units long and in the direction you were pointing.

Obviously, you could vary this sequence to get different effects. If you only want to draw horizontal or vertical lines, you could use Ortho rather than Polar Tracking. Or, you could configure polar tracking to snap to other angles like 45º or 30º. You might even want to turn both Ortho and Polar Tracking off and use free angles.

SNAP- This is a drawing mode that allows you to snap your cursor to precise point laid out in grid pattern.

Statusbar SNAP Keyboard F9

GRID- Pattern of dots displayed on screen to guide you.

Statusbar GRID Keyboard F7

ORTHO- Ortho is short for Orthogonal, which . means either Horizontal or vertical.

Statusbar ORTHO Keyboard F8

POLAR- Allows you to snap into angles you choose to configure.

Statusbar POLAR Keyboard F10

OTRACK

Statusbar OTRACK Keyboard F11

Object Snaps (OSNAP)

Suppose you want to draw a line from the center of the circle to the middle of the vertical line you extended earlier. AutoCAD has a feature that makes this very easy. These are the Object Snaps (or Osnaps "Oh-Snaps"). Type OS <ENTER> . You will see this dialog box appear.

You may select whichever points you want to 'snap' on an object. Here is a list of your options. Followed by the command entry to invoke the needed Osnap.

Endpoint - snaps to either the beginning or the end of an object such as a line - END

Midpoint - snaps to the exact middle of a line or an arc - MID

Center - snaps to the center-point of a circle or arc - CEN

Node - snaps to 'nodes' (not covered in this course) - NOD

Quadrant - snaps to any of the four quadrants of a circle - QUA

Intersection - snaps to the point where two object cross - INT

Extension - Snaps to the phantom extension of an arc or line - EXT


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AUTOCAD Insertion - snaps to the insertion point of an object (such

as a block or text) - INS Perpendicular - will snap so that the result is

perpendicular to line selected - PER Tangent - snaps to create a line tangent to a circle or arc

- TAN Nearest - will find the closest point an object and snap

to that point - NEA Parallel -Snaps parallel to a specified line - PAR None - temporarily turns off all Osnaps. (Pressing your

F3 Key is quicker) - NON Osnap settings - opens the Osnap dialog box. Temporary Tracking - Creates a temporary tracking

point

CIRCLE

The circle command is used to draw circles. There are number of ways you can define the circle.

The default method is to pick the center point and then to either pick a second point on the circumference of the circle or enter the radius at the keyboard.

Draw toolbar

Pull down menu>Draw> Circle>Center>Radius

Keyboard CIRCLE or C

RECTANGLE

The rectangle command is used to draw a rectangle whose sides are vertical or horizontal. Th position and size of the rectangle are defined by picking two diagonal corners.

Draw toolbar

Pull down menu > Draw > Rectangle

Keyboard RECTANGLE or REC

COPY- To make a duplicate of selectd object

Modify toolbar

Pulldown menu > Modify > Copy

Keyboard COPY or CO

MOVE- To transfer an object from one place to another.

Modify toolbar

Pull down menu > Modify > Move

Keyboard MOVE or M


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AUTOCAD DTEXT

Keyboard DTEXT or DT

MULTITEXT

Draw toolbar A

Keyboard MULTITEXT or MT

ALIGN- Allows you to enter boundary, text will

Automatically adjust height and length to

fit.

FIT- Allows you to enter boundary, text will

Automatically adjust length to fit.

CENTER- Allows you to specify the center of

text.

MIDDLE- Allows you to specify the middle of

text.

TL- Allows you to specify the topleft of text.

TC- Allows you to specify the top center of text.

TR- Allows you to specify the top right of text

ML- Allows you to specify the middle left of text.

MR- Allows you to specify the middle right of

text.

BL- Allows you to specify the bottom left of text.

BC-Allows you to specify the bottom center of

text.

BR- Allows you to specify the bottom right of

text.

SPELL- Corrects the spelling in text objects created with TEXT, MTEXT, LEADER, and ATTDEF. The Check Spelling dialog box is displayed only if AutoCAD finds a misspelled or unknown word in the specified text

SOLID- Creates solid-filled triangles and quadrilaterals

Keyboard SOLID or SO

SCALE- The Scale command can be used to change the size of an object or group of objects

Modify Toolbar SCALE

Pull down menu Modify .> Scale

Keyboard SCALE or SC

ROTATE- The Rotate command allows an object or objects to be rotated about a point selected by the user. AutoCAD prompts for a second rotation point or an angle which can be typed at the keyboard.

Modify toolbar ROTATE

Pull down menu > Modify > Rotate

DONUT- This command allows you to draw a solid donut shape.

Pull down menu > Donut

Keyboard DONUT or DO


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AUTOCAD

OBJECT SELECTION

SELECTING OBJECT BY PICKING-

Perhaps the most obvious way to select an object in AutoCAD is simply to pick it.

1.WINDOW SELECTION-

The Window option is invoked by typing W in response to the "Select objects" prompt. Window allows you to define a rectangle using two points in exactly the same way as the RECTANGLE command. Once the window is defined, all objects which lie entirely within the window will be selected.

2.CROSSING WINDOW SELECTION

The Crossing Window option is invoked by typing C at the "Select objects" prompt and is a variation of the Window command. The command sequence is exactly the same but objects are selected which lie entirely within the window and those which cross the window border

3.FENCE SELECTION-

The Fence option allows you to draw a multi-segment line, like a Polyline. All objects which

cross the fence will be selected. The Fence option is invoked by typing F at the "Select objects" prompt

4.WINDOW POLYGON SELECTION

The Window Polygon option, invoked by typing WP is similar to the Window option except that you can define an irregular polygon shape within which objects will be selected. As with the Window option, only objects which fall entirely within the polygon will be selected.

5.CROSSING POLYGON SELECTION

The Crossing Polygon option can be used in exactly the same way as the Window Polygon option but it has the same selection criteria as the Crossing Window option, i.e. objects will be selected if they fall entirely within or touch the polygon boundary. This option is invoked by typing CP at the "Select objects" prompt.

6.USING PREVIOUS SELECTION

AutoCAD always remembers the last selection set you defined. This is very useful because you may need to make a number of changes using different commands to the same group of objects. In order to re-select the last selection set you can use the Previous option. The previous option is invoked by typing P at the "Select objects" prompt.

7.SELECTING THE LAST OBJECT

You can select the last object created by entering L at the "Select objects" prom

TIP AutoCAD Dynamic Viewing

.* Realtime Pan -- drag mouse while holding down middle button (wheel). * Joystick Pan -- drag while holding down Ctrl key and middle button. The scene moves around you. * Realtime 3dOrbit -- drag while holding down Shift key and middle button. You move around the scene.for AutoCAD 2007 up

* Realtime Zoom -- roll the wheel. * Zoom to Extents -- double-click the wheel.


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AUTOCAD

TOOLPALETTES

1. For example, you would like to publish some

standard parts that are commonly used by your

company. The most practical way to do this is

classifying your blocks into groups that you will

determine by yourself and store them together.

Besides, all of the blocks ( “Part01”, “Part02” and

“Part03” ) that are shown below are all stored in

the same drawing file and “Library01.dwg” name

was used as the filename. These blocks inside the

drawing represent different cover parts and are

organized in a logical way.

One of the biggest advantages of storing blocks

all together inside the same drawing is that

AutoCAD files don’t occupy much space. By this

way, it will be easier to use the same file for

searching files and changing any property of the

block.

Figure 1

2. If the TOOLPALETTE is not seen on the screen,

then you can use either TOOLPALETTES

command, Tool/Tool Palettes menu command

or ‘CTRL+3’ button combination. Press the right

mouse button and enter ‘New Palette’

command. Then, create a new library (page, tab).

Figure 2

3. I gave the name of ‘MyBlock‘ to the new tab,

of course you can name it in different ways.

Figure 3

4. Let TOOLPALETTE stay on the screen. Now, we

will open DESIGNCENTER‘ by using ‘CTRL+2’

button combination and enter the location of

“Library01.dwg” file that I explained above into

the ‘Folders’ section. When you click on the

‘Blocks’’ from tree-menu, you can see the blocks

that exist inside this drawing. You can ‘Drag and


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AUTOCAD

Drop’ the blocks that you can see here from

window number (1) to window number (2). You

can select the blocks one by one by using ‘SHIFT

+ Left mouse button’.

Figure 4

5. As a result of this operation, AutoCAD will

prepare ‘Thumbnail’ views for all of the blocks

here.

Figure 5

6. You can change the names and several

properties of blocks by using ‘Properties’ option.

DASHBOARD

DASHBOARD feature that came together with

AutoCAD 2007 is providing such a functionality.

Even though DASHBOARD is more or less some

kind of a TOOLPALETTE, it has some particular

differences. Controls on it are slightly different.

Besides, you cannot add tabs to DASHBOARD.

You cannot customize DASHBOARD in AutoCAD

2007, but since AutoCAD 2008 it is customizable

now. However, usage of DASHBOARD is mainly

based on control panels rather than tabs. Now,

let’s start learning by taking a look at how

DASHBOARD looks first (Fig. 1).


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AUTOCAD

Fig.1

In Fig. 1, you can see the DASHBOARD that

belongs to AutoCAD 2008. Please note that each

control panel is divided by a line. Each panel

consists of controls like mini buttons, combo lists,

sliding bars etc. That is the main difference

compared to TOOLPALETTEs. Moreover, each

panel can expand in between each other (Fig. 2).

Fig.2

Expanding and contracting operations are done by

using the double arrow icon in down direction (

expanding ) or double arrow icon in up direction

(contracting ) that can be found just beside the

large icon that represent each panel. Its usage is

pretty simple. DASHBOARD, similar to

TOOLPALETTE, can be either docked or can be

opened/closed automatically. We can make these

settings from the mini menu that is just under the

gray ( or blue ) band.

Fig.3

If you also would like to have wide drawing area

like me, then you can choose the ‘auto-hide’

option. It is also possible to open or close

different control panels again from the same

menu. Before finishing the article, let me remind

you once more how to open or close

DASHBOARD. If the dashboard is closed then you

can open DASHBOARD by entering DASHBOARD

from command line or select Dashboard from the

Window menu.


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AUTOCAD

EXTEND- This command extends a line, polyline or arc to meet another drawing object (known as the boundary edge). In the illustration on the right, two lines (red) are extended to meet another line (cyan) which forms the boundary edge. This command works in a similar way to the Trim command

Modify toolbar

Pull down menu > Modify > Extend

Keyboard EXTEND or E

TRIM- The Trim command can be used to trim a part of an object. In order to trim an object you must draw a second object which forms the "cutting edge". Cutting edges can be lines, xlines, rays, polylines, circles, arcs or ellipses. Blocks and text cannot be trimmed or used as cutting edges

Modify toolbar

Pull down menu > Modify > Trim

Keyboard TRIM or TR

FILLET- The Fillet command is a very useful tool which allows you to draw an arc between two intersecting lines or adjacent polyline segments. You first need to use the command to set the required radius and then a second time to select the two lines.

The Fillet command can also be used to fillet arcs and circles. The "Polyline" option also allows you to fillet all vertices of a polyline with a single command. It's worth experimenting with this command, it can save you lots of time and enables you to construct shapes which otherwise would be quite difficult

Modify toolbar

Pull down menu > Modify > Fillet

Keyboard FILLET or F

CHAMFER- The Chamfer command enables you to create a chamfer between any two non-parallel lines as in the illustration below or any two adjacent polyline segments. Usually, the Chamfer command is used to set the chamfer distances before drawing the chamfer.

Modify toolbar

Pull down menu > Modify > Chamfer

Keyboard CHAMFER or Cha

MIRROR- defining the position The Mirror command allows you to mirror selected objects in your drawing by picking them and then of an imaginary mirror line using two points

Modify toolbar

Pull down menu > Modify > Mirror

Keyboard MIRROR 0r MI

OFFSET- Offset is probably one of the most useful commands for constructing drawings. The Offset command creates a new object parallel to or concentric with a selected object. The new object is drawn at a user defined distance (the offset) from the original and in a direction chosen by the user with a pick point. You can offset lines, arcs, circles, ellipses, 2D polylines, xlines, rays and planar splines.

Modify Toolbar

Pull down menu > Mody > Offset

Keyboard OFFSET or O

Setting Colour and Linetype "ByLayer"

AutoCAD offers two methods of setting the colour and linetype of a drawing object. First of all, colour and linetype can be set ByLayer. In other words, an object will be displayed in the colour and linetype of its layer. For example, if you draw a circle on a layer which you have called "Detail" and you have


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AUTOCAD also set the colour of Detail to blue and the linetype to dashed, then the circle will be displayed in a dashed blue line. When an object takes on the properties of its layer, the colour and linetype are said to be set "ByLayer".

The second method AutoCAD offers is to set the colour and linetype by object. Setting properties by object overrides those set ByLayer. In general it is good drawing practice to set colour and linetype properties ByLayer, this is more efficient and less confusing in the long-run. For example, imagine that you have drawn hundreds of objects on the same layer and have set their colour to green. Later in the drawing process you decide that these objects should, in fact, be yellow. In order to make the change you would have to use the Properties command and select every one of the objects by picking them. By contrast, if you had set the objects colour to ByLayer, you would only have to change the layer colour from green to yellow and all of the objects would change.

There are times , however, when in is useful to be able to set colour and linetype properties by object. Setting properties by object is covered later in this tutorial. The following sections cover the setting of colour and linetype ByLayer.

Setting the Colour of a Layer

It is often convenient to set the layer colour when the layer is created, although this can be done at any time. The layer colour can be changed as many times as you like. Each time it is changed, any objects on that layer will change to the new colour, providing their colour is set to "ByLayer".

the two logical colour buttons, ByLayer and

ByBlock are no longer greyed-out.

To set a layer colour, open the Layer & Linetype Properties dialogue box, click on and then click on the colour icon in the layer list associated with the layer you want. Notice that all layers have their own colour icon and that this changes to display the layer colour. Clicking on the icon brings up the Select Color dialogue box, shown on the right. You can select any of the 255 standard AutoCAD colours by picking on the colour palette or by

entering the colour name or number in the text edit box. When you have selected the colour you want, click on the "OK" button to set the colour. AutoCAD uses only 255 colours plus the drawing background colour, irrespective of the capabilities of your video display.

Assigning different colours to your layers will make working with complex drawings much easier. You will be able to see at a glance what a particular line represents. For example, your construction lines may be on a layer called "Construction" and have the colour yellow. This will visually differentiate these lines from lines on other layers with different colours.

Setting the Linetype of a Layer

In the same way that you can assign a colour to a layer you can also assign a linetype to a layer. For example, you could have all the lines on a layer called "Construction" display in a yellow dashed line. To set a linetype to a layer, click on and then click on the current linetype name associated with your layer in the layer list. By default, layers have the "Continuous" linetype. Clicking on the linetype name brings up the Select Linetype dialogue box, shown on the right. You will notice that the "Continuous" linetype is the only one listed. That's because all linetypes, except "Continuous", are stored in an external file and have to be loaded before they can be used.

Loading Linetypes


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AUTOCAD To load a linetype, click on the "Load..." button in

the Select Linetype dialogue box. The Load or Reload Linetypes dialogue box appears and displays a list of the available linetypes. Select as many of the listed linetypes as you wish and then click the OK button to return to the Select Linetype dialogue box.

Selecting from list boxes works the same way in AutoCAD as it does in any other Windows application. For example, if you wish to select a block of linetypes from the list at one time, select the first linetype in the block, hold the Shift key down on the keyboard and select the last linetype in the block. All linetypes in the block will be highlighted and you can click the "OK" button to load them all in one go. You can also hold the Control (Ctrl) key down on the keyboard to make multiple selections which aren't adjacent in the list (see illustration above).

When you return to the Select Linetype dialogue box the loaded linetypes are displayed in the list. To assign a particular linetype to a layer, simply click on the name to highlight it and then click on the OK button. When you return to the Layer & Linetype Properties dialogue box, the new linetype name will be listed against your layer in the "Linetype" column. From now on, all objects drawn on this layer will be drawn with the chosen linetype. However, just like colours, you may change the linetype at any time and the objects drawn on that layer will automatically be updated to display the new linetype.

Colours

In the same way that you can set a current layer, you can set a current colour so that every object you draw will be displayed in a particular colour irrespective of which layer it is on. As mentioned earlier, this method of assigning colour, by object, is recommended only in special circumstances. In general, colour should be assigned ByLayer. See Setting Colour and Linetype "ByLayer" for more information.

To set a current colour, simply click on the "Color Control" box on the Object Properties toolbar. The drop-down list contains the two logical colours ByLayer and ByBlock, the seven standard AutoCAD colours, Red, Yellow, Green, Cyan, Blue, Magenta and White (colour numbers 1 to 7 respectively) and the "Other..." option. Notice that the default colour for any new drawing is "ByLayer", this is because in most circumstances you will want to assign colours by this method. Select a colour directly from the drop-down list or click on the "Other..." option to bring up the Select Color dialogue box (illustrated below) where you can select any of the AutoCAD colours from the Full


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Linetypes

As with layers and colours, a current linetype can be set so that all objects drawn will be displayed with that linetype. However, the same warnings given above about assigning colour by object also apply to assigning linetypes by object, namely that linetypes should be set ByLayer wherever possible. That said, to set a current linetype, click on the "Linetype Control" box on the Object Properties toolbar, and select a linetype from the drop-down list. The list contains the two logical linetypes, ByLayer and ByBlock, these have the same function as the two logical colours of the same name and a list of the currently loaded linetypes.

If you have just started a new drawing the only true linetype available will be the "Continuous" linetype. Before you are able to assign any other linetype, you must first load the linetypes you may need. To load linetypes you must use the "Linetype" command. Click on the button on the Object Properties toolbar. You will now see the familiar Layer & Linetype Properties dialogue box but this time the "Linetype" tab is automatically selected to display the linetype information, see illustration below

In the Layer & Linetype Properties dialogue box, click on the "Load..." button, this brings up the Load or Reload Linetypes dialogue box which you have seen previously in this tutorial. Select the required linetypes from this dialogue box and then click the "OK" button to return to the Layer & Linetype Properties dialogue box, where you will see the newly loaded linetypes in the Linetype list. This selection process is the same as that described in the "Loading Linetypes" section of this tutorial, above. Now that the required linetypes have been loaded you can set the current linetype either by highlighting it in the Linetype list and then clicking the "Current" button in the Layer & Linetype Properties dialogue box or you can simply select the linetype from the drop-down list in the Object Properties toolbar.

Setting the Linetype ScaleIn many cases your linetypes will display just as you want them. However, it is inevitable that at some time you will need to change the scale at which your linetypes are displayed. By default the linetype scale is set to 1.0, this means that each linetype pattern will repeat every 1.0 drawing units. To make the pattern appear larger, change the scale to a larger number. Setting the linetype scale to 5.0 for example causes the linetype pattern to repeat every 5.0 drawing units so that the pattern will appear 5 times larger. Conversely, setting the scale to 0.2 causes a repetition every 0.2 drawing units which will make the pattern appear 5 times smaller. See the illustrations below.


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To change the linetype scale, click on the button to bring up the Layer & Linetype Properties dialogue box. If the "Details" section of the dialogue box is not visible, click on the "Details>>" button to reveal it. The dialogue box should now look similar to the one shown above. You set the linetype scale by changing the value in the "Global scale factor" edit box. Once you have changed the scale factor, click on the OK button to return to your drawing. AutoCAD automatically regenerates the drawing to display all linetypes with the new scale factor.

You may have noticed from the Layer & Linetype Properties dialogue box that you can also set the linetype scale by object, using the "Current object scale" edit box. Whilst this is perfectly easy to do, the results can sometimes be unexpected, since the linetype scale of any object is a function of both the Global and Current scales. For example, setting the Global scale to 2.0 and the Current scale of an object to 0.5 results in the same appearance as if both scales were set to 1.0, the default values. In short, unless you have a really compelling reason to change it, keep the Current object scale set to 1.0, this will avoid any confusion in the future.

MATCH PROPERTIES

Another way to change the properties of an object or objects is to match the properties of any other object using the Match Properties command on the Standard toolbar

Pull down menu > Modify > Match Properties

Keyboard MATCH PROP or MA

BHATCH- Fills an enclosed area or selected objects with a hatch pattern or gradient fill

Draw toolbar

Pull down menu > Draw > Hatch

Keyboard BHATCH or H

Start the Boundary Hatch by typing H <ENTER> . When you start the command, you will see this dialog box appear:

As usual, start at the top of the dialog box and work your way down. We're going to say that this is a cross section of piece of steel, so choose the predefined Hatch pattern called STEEL.


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Set the scale of the hatch to 6. This is just a number that works for this object. A larger number will make the hatch bigger (maybe so big you won't see it) and a smaller number can make the hatch so dense that it looks solid (try different numbers later to see if I'm wrong).

Make this "Associative" - this means that if you adjust the rectangle or circle, the hatch will automatically correct itself to the new boundary.

Finally, hit the Preview button to see if this is what you are after, it should match the image below.

DIMENSION PARTS

Also, you can modify the dimension text dramatically, here are some examples:

Introduction This tutorial describes the options and commands available for dimensioning

drawings and how to use them. The correct use of AutoCADs dimension tools is the key to producing clear and concise measured drawings. If you just need to quickly find a description of the various dimension commands, click on the appropriate button on the QuickFind toolbar below.

AutoCAD provides a whole range of dimensioning tools which can be used to quickly dimension any drawing without the need for measurement. Dimensioning in AutoCAD is automatic; lines, arrows and text are all taken care of by the dimension commands. AutoCAD dimensions are special blocks which can easily be edited or erased as necessary.

AutoCAD provides lots of control over the way dimensions look. Using a system similar to text styles, dimension styles allow you to design dimensions so that they look just the way you want them to.


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For example, the illustration above shows two different dimension styles. The one on the left is the default style known as STANDARD. If you do not create a style of your own or modify the standard style, all dimensions will look like this. The dimension line has arrow heads and the dimension text is positioned above the line and is drawn using the current text style. The dimension on the right has been drawn using a new style. The arrows have been changed to obliques, the vertical alignment of the text has been centred and the current text style has been changed.

There are lots of dimension commands which include facilities for indicating tolerances and alternate units dimensioning. However, this tutorial aims to cover the most common commands for general use and constitutes an introduction to dimensioning with AutoCAD. If you would like to learn more about dimensions, refer to the AutoCAD user manual.

AutoCAD divides dimensions into four main categories: Linear, Radial, Ordinate and Angular. For the purposes of this tutorial we will only consider some of the commands within the Linear, Radial and Angular categories.

When you create dimensions, AutoCAD automatically creates a new layer called "Defpoints". This is a special layer which cannot be deleted or renamed. AutoCAD uses this layer to store dimension information and you can effectively ignore it. (see Object Properties for more information on layers)

When working with dimensions it is very important that line origins are picked accurately so that the resulting measurement and text are correct. Always use an Osnap to pick dimension

line

origins. If you have a lot of dimensioning work to do, it will be worth using a running Osnap. Running object snaps are set using the Osnap Settings dialogue box. To display this dialogue box type DDOSNAP at the keyboard or select Tools/Object Snap Settings from the Pull-down menu. There is also a keyboard short-cut; you can display the Osnap Settings dialogue box simply by hitting the F3 key.

This tutorial is not designed as a reference for dimensioning conventions. If you wish to learn more about dimensioning conventions, consult BS 308: Part 2.

Selecting Dimension Commands Selecting and working with the dimension commands in AutoCAD R14 is much easier than in previous versions. All commands can be accessed from the keyboard and now most commands are also available from the Dimension pull-down menu and the Dimension


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toolbar. The Dimension toolbar is particularly useful because it places all the dimension commands a single mouse click away. Since the Dimension toolbar is not displayed by default you will need to enable it from the Toolbars dialogue

box. To display the Toolbar dialogue box, select View/Toolbars… from the pull-down or type TOOLBAR at the keyboard. To display the Dimension toolbar, click in the checkbox against "Dimension" in the toolbar list.

The Linear Dimension Commands As the name suggests the Linear dimension commands are used to dimension along straight lines. There are five linear dimension commands, namely: DIMLINEAR, DIMCONTINUE, DIMBASELINE, DIMALIGNED and DIMROTATED. The DIMLINEAR command is probably the most common dimension command you will use.

The Linear Dimension Command

Toolbar Pull-down Dimension/Linear

Keyboard DIMLINEAR

You can use this command to generate horizontal and vertical dimensions. Creating a linear dimension is easy. All you have to do is start the command, specify the

two points between which you want the dimension to be drawn and pick a point to fix the position of the dimension line. Consider the diagram

(right) whilst working through the following examples.

Command Sequence Command: DIMLINEAR First extension line origin or press ENTER to select: (pick P1) Second extension line origin: (pick P2) Dimension line location (Mtext/Text/Angle/Horizontal/Vertical/Rotated): (pick a point to position the dimension line, you will see the dimension rubber banding)

You may have noticed that the first prompt asks you to pick the first extension line origin or to press the ENTER key. Pressing the Enter/Return key results in the following prompt:

Select object to dimension:

AutoCAD allows you to dimension an object simply by picking it. Try this out. Draw a line or a circle and use this option rather than the two point option to see what happens.

Dimensions will automatically adjust themselves to accommodate most situations. For example, the illustration on the right shows what happens to a dimension if the gap between the two extension lines is too small for the dimension text.

The Continue Dimension Command

Toolbar Pull-down Dimension/Continue

Keyboard DIMCONTINUE


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You can use the Continue command to add a string of dimensions. In the illustration above the "36mm" dimension has been continued from the "64mm" dimension.

Command Sequence Command: DIMCONTINUE Specify a second extension line origin or (Undo/<Select>): (pick P3) Specify a second extension line origin

or (Undo/<Select>): (pick another or to end) There is no prompt for the first line origin, AutoCAD automatically selects the second line origin of the previous dimension to be the first of the new dimension. There is also no prompt for the dimension line position, AutoCAD automatically matches up with the previous dimension.

Using the Continue command you can very quickly generate a string of dimensions which align perfectly. In the example above, the "34.41" dimension was drawn with the DIMLINEAR command; all the other dimensions were drawn using the DIMCONTINUE command and simply picking the four points, one after the other. You can only continue a dimension in a single direction. To generate the "26mm" dimension in the previous illustration, you will need to use the DIMLINEAR command and pick P3 and P4 or enter at the first prompt and pick the line. The Baseline Dimension Command

Toolbar Pull-down Dimension/Baseline

Keyboard DIMBASELINE

You can use this command to generate a series of dimensions from a single base point. You must already have created the first dimension in the sequence using a command such as DIMLINEAR. The DIMBASELINE command then creates further dimensions in a similar way to the DIMCONTINUE command. All the user has to do is pick points.

Command Sequence Command: DIMBASELINE Specify a second extension line origin or (Undo/<Select>): (pick next point) Specify a second extension line origin

or (Undo/<Select>): (pick another or to end) Select base dimension: ( again to end)

In the example above, the "35.07" dimension was created using the DIMLINEAR command. The others were created using DIMBASELINE and picking points 1 and 2.

The Aligned Dimension Command

Toolbar Pull-down Dimension/Aligned

Keyboard DIMALIGNED


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You can use this command to generate aligned dimensions. These are dimensions along inclined lines which cannot be dimensioned with the DIMLINEAR dimension command because that command will only give a measured dimension in either a horizontal or vertical direction. However, as you can see from the command sequence below, this command works in exactly the same way.

Command Sequence Command: DIMALIGNED First extension line origin or press ENTER to select:(pick P1) Second extension line origin: (pick P2) Dimension line location (Mtext/Text/Angle): (pick a point)

The DIMCONTINUE and DIMBASELINE commands can both be used in conjunction with DIMALIGNED dimensions.

Changing the Text You may have noticed that when you are prompted to pick the dimension line location you are also offered a number of options. The options vary depending upon the particular command that you are using. However, the Mtext and Text options, which are common to all dimension commands are particularly useful. Essentially they do the same thing, they allow you to change the text which will appear on the dimension line. The Text option allows you to enter a single line of text and the Mtext option starts the MTEXT command and enables you to add formatted, multiline text to the dimension. These options can be used to add descriptions to your dimensions or to modify the measured distance.

In the example above, the Mtext option has been used to create a multi-line annotation. When you use this option you will notice that the Multiline Text Editor dialogue already has some text in the text window. This is the measured dimension and is displayed as "<>". If you delete this marker the dimension measurement will not appear in the annotation.

If you need to edit dimension text after the dimension is drawn, you can use the DDEDIT command, Modify/Object/Text… from the pull-down. If you select a dimension, the Multiline Text Editor will appear and you can make any necessary changes to the annotation.

The illustration on the right shows an extract from the Multiline Text

Editor as it would appear if the dimension above were selected.

The Radial Dimension Commands There are two main radial dimension commands, DIMDIAMETER and


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DIMRADIUS. Both commands result in a similar looking dimension so AutoCAD automatically inserts a "R" to indicate a radius and the dimension symbol to indicate a dimension. You can get AutoCAD to display the dimension symbol by including "%%c" in any text string. For example, in order to draw the 40mm diameter text as it is shown in the

illustration on the right, you would need

to type "%%c40mm". You can use this special character with any of the text commands.

The Diameter and Radius commands are supplemented by the DIMCENTER command which can be used to add a center mark to any circle or arc. The DIMDIAMETER and DIMRADIUS commands do not automatically draw a center mark.

By convention it is usual to dimension full circles using a diameter and arcs (partial circles) using radius. You will find more information on dimensioning conventions in BS 308: Part 2.

The Diameter Dimension Command

Toolbar Pull-down Dimension/Diameter

Keyboard DIMDIAMETER

You can use the Diameter command to annotate a circle or an arc with a diameter

dimension. To achieve this simply start the command, pick a point on the circumference of the circle, pick a second point to determine the length of the leader and then add the dimension text or Return to accept the default.

Command Sequence Command: DIMDIAMETER Select arc or circle: (pick the circumference P1) Dimension line location (Mtext/Text/Angle): (move the cursor until you are happy with the text position and then pick to complete the sequence)

The Radius Dimension Command

Toolbar Pull-down Dimension/Radius

Keyboard DIMRADIUS

The Radius command is identical to the Diameter command except that the dimension measurement is a radius rather than a dimension and the resulting dimension text is prefixed with a "R" to indicate radius.

Command Sequence Command: DIMRADIUS Select arc or circle: (pick the circumference P2) Dimension line location (Mtext/Text/Angle): (move the cursor until you are happy with the text position and then pick to complete the sequence)

Notice that in the illustration above the radius dimension has been positioned inside the circle. Both diameter and radius dimensions can be positioned either inside or outside an arc or circle.


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Practice with the Radial and Diameter commands until you understand how they work.

The Center Mark Command

Toolbar

Pull-down Dimension/Center Mark

Keyboard DIMCENTER

You can use the Center Mark command to annotate a circle or an arc with a cross at the center. The illustration above shows a center mark added to a circle after a diameter has been drawn.

Command Sequence Command: DIMCENTER Select arc or circle: (Pick the circumference of a circle or arc) A cross is drawn at the center point.

Angular Dimensions There is only one command in this section and it is used to annotate angular measurements.

The Angular Dimension Command

Toolbar Pull-down Dimension/Angular

Keyboard DIMANGULAR

The Angular command is amazingly flexible and can be used to indicate an angle in almost

any situation. Just like the other dimension commands, all parts of the process are rubber banded so you can see the results of your actions before you make the final

pick.

Command Sequence Command: DIMANGULAR Select arc, circle, line, or press ENTER: (pick a line) Second line: (pick another line) Dimension arc line location (Mtext/Text/Angle): (pick point) Move the cursor position until you are happy with the result. Notice that you can move the cursor to either side of the lines and the angular dimension will change accordingly.

You may have noticed that at the first prompt you are given the option to press ENTER. If you use this option you will be prompted to pick the angle vertex and then the two angle endpoints. This is quite useful if the angle you need to dimension is not defined by physical lines on the drawing. The illustration on the right shows the result of this option. The centre point of circle 1 was picked as the angle vertex and the centre points of circles 2 and 3 were picked for the two angle endpoints.

The degree character is automatically inserted for you, however, if you ever need to type it, you can do so by typing "%%d". This is another of AutoCADs special characters.

Ordinate Dimensions Ordinate dimensions are not really dimensions at all in that they do not indicate a measurement. Rather they annotate known co-


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ordinate points. The DIMORDINATE command is used to indicate the X and Y ordinate values at any point.

The Ordinate Dimension Command

Toolbar Pull-down Dimension/Ordinate

Keyboard DIMORDINATE

The Ordinate command is used to annotate co-ordinate points with X or Y values. This may be useful for setting-out on site plans.

Command Sequence Command: DIMORDINATE Select feature: (pick the point to annotate) Leader endpoint (Xdatum/Ydatum/Mtext/Text): (pick endpoint or use one of the options)

By default a vertical leader will display the X ordinate and a horizontal one will display the Y ordinate. However, you can use the Xdatum and Ydatum options to override this default.

In the illustration above, the building corner on the left has been annotated with X and Y ordinates using the default method. The one on the right has a Y ordinate which has been forced to display in a vertical position using the Ydatum option. You could also use the Text or Mtext options to clearly describe the point you are annotating.

Annotation with

Leaders Ordinate dimensions are not really dimensions at all in that they do not indicate a measurement. Rather they annotate known co-ordinate points. The DIMORDINATE command is used to indicate the X and Y ordinate values at any point.

The Leader Command

Toolbar Pull-down Dimension/Leader

Keyboard LEADER

The Leader command can be used to annotate any point on a drawing. The command sequence below was used to draw the leader shown in the illustration above.

Command Sequence Command: LEADER

From point: (pick the point to annotate) To point: (pick vertex point) To point (Format/Annotation/Undo)<Annotation>: (pick end point) To point (Format/Annotation/Undo)<Annotation>:

Annotation (or press ENTER for

options): Corner of MText: building MText: (to end)

Unlike other dimension commands the leader and annotation text are drawn as separate objects. So, if you need to move or edit the


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text, you can do so without affecting the leader line.

As you can see by the command line, there are a number of options with this command including "Format" options which include "Spline". Experiment with these options until you understand them.

Editing Dimensions The dimension edit commands, DIMEDIT and DIMTEDIT are used primarily to adjust the position of the text part of a dimension. This is usually only necessary if the drawing is quite complex and the dimension would read more clearly if it were in a different position.

The Dimension Text Edit Command

Toolbar Pull-down Dimension/Align Text/options

Keyboard DIMTEDIT

The Dimension Text Edit command is used to modify the text position of any single dimension. The command can be used to position the text dynamically (this is the default)or one of the options can be used for a specific type of movement. For example, the dimension shown on the right has been modified by dynamically moving the position of the text and then the text has been rotated using the Angle option.

Command Sequence Command: DIMTEDIT Select dimension: (pick the dimension you want to edit) Enter text location (Left/Right/Home/Angle): (pick a new position or use an option)

The results of the four available options are shown in the illustration below.

The Left option moves the text to a left justified position within the dimension.

The Right option moves the text to a right justified position within the dimension.

The Home option returns the text to the home position after it has been modified.

The Angle option enables the text to be rotated about its center.

The Dimension Edit Command

Toolbar

Pull-down

Dimension/Oblique (other options are duplicated in DIMTEDIT so don't appear)

Keyboard DIMEDIT

The Dimension Edit command can be used to modify and change the text of any number of dimensions. The command could, for example, be used to add a standard prefix or suffix to a number of dimensions.

Command Sequence Command: DIMEDIT Dimension Edit (Home/New/Rotate/Oblique) <Home>: (choose an option) Select objects: (pick one or more dimensions) Select objects: (pick more or end)

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results of the various options are illustrated below.

The Home option returns dimensions to their home position.

The New option displays the Multiline Text Editor. The changes you make to the text will be applied to all selected dimensions so it is important not to delete the "<>" marker from the text string. Deleting this marker will remove the values from all selected dimensions.

The Rotate option can be used to rotate dimension text about its center point. It works in exactly the same way as the Angle option of the DIMTEDIT command except that you can rotate any number of dimensions at once.

The Oblique option is used to set the dimension lines at an angle. This option can be very useful when you are dimensioning a drawing in isometric projection (see the illustration on the right). In this case the drawing has been dimensioned using the Aligned command and then the oblique angle modified to suit the dimension position. This usually means setting an angle of 30, 330 or 90 degrees depending upon the dimension orientation. If you are creating details in isometric projection make sure you are using the isometric snap/grid option for greater efficiency. For more information on drawing in isometric projection and the use of the isometric snap grid, see the "Drawing Aids" tutorial.

Dimension Styles Dimension styles are the main method used to control the way dimensions look. Using styles you can change the text font, the arrow head

style, the relative position of the text, the scale of dimensions and many other parameters. Styles are created using the DIMSTYLE command.

Dimension styling is a relatively complex area of AutoCAD and the finer points are beyond the scope of this tutorial. However, the main points which will enable you to create clear, good looking styles are set out below.

Dimension Style Command

Toolbar

Pull-down Dimension/Style…

Keyboard DDIM short-cut D

The Dimension Style command can be used to change the appearance of dimensions. The best method is to create a new style before you start

creating dimensions so that you can leave the STANDARD style as a default option. Having created a new style from STANDARD you can then apply any modifications you generally require to the parent style and then

more specific modifications to the child styles in order to create a style family.


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Dimension styles are created using the Dimension Styles dialogue box. The dialogue box is shown on the right. As you can see from the dialogue box, a style is applied to a family of dimensions. By default, any style changes are made to the parent. Each style parent has six child styles. The child styles, Linear, Radial, Angular, Diameter, Ordinate and Leader can be used to modify the parent style when that particular type of dimension is used. For example, you may like to use a tick rather than an arrow head for your dimensions but this isn't really appropriate for a leader, so the Leader child style can be changed so that leaders will always be drawn with an arrow head whilst all other dimensions of the same style family are drawn using ticks.

Creating a new style To create a new dimension style, make sure the STANDARD style is the current style, click in the Name edit box and type the name of the new style you wish to create. Click the Save button. You will see a message in the lower left corner of the dialogue box which says "Created name from STANDARD" where name is the new style name which you typed. The new style is automatically set as the current style. You may rename the new style if you wish, simply by typing a new name in the Name edit box and clicking on the Rename button.

The new style which you have created is identical to the STANDARD style, so you must now modify your new style so that it can be used to create dimensions which conform to your own requirements. Style changes are made in three categories, Geometry, Format and Annotation. As you can see from the Dimension Styles dialogue box, each category is represented by a button which leads to a dialogue box which is used to modify the settings in that particular category.

Setting the Arrow Head Type The style of arrow heads is set using the Geometry dialogue box, illustrated above. As you can see, the STANDARD style has Closed Filled arrow heads as a default.To change the arrow head style for a new dimension style, make sure the style is current and that the "Parent" radio button is selected (this assumes you are not modifying a child style), click on the "Geometry…" button and select a new arrow head type from the "1st" drop-down list. Once selected the new arrow type is illustrated in the dialogue box. If you require different arrow heads at each end of your dimensions you can set the other type using the "2nd" drop-down list. Click on "OK" to return to the Dimension Styles dialogue box.

Dimension Scale When you are working with drawings which will be plotted at different scales, you will need some way of changing the scale of the dimension lines relative to your drawing so that they always appear the same size, irrespective of plotting scale. You can achieve this by using the Scale variable. This option is also available from the Geometry dialogue box. The default


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value is set to 1.0. The larger the value the larger the dimension will appear. For example, a value of 2.0 would double the text height and the arrow size. To change the scale of dimensions, simply type the required scale in the "Overall Scale" edit box. Try changing the scale factor and check the results. The scaling applies to individual styles, so you could create different styles with different dimension scales to be used for different plotting scales.

Note that changing the scale of dimensions does not affect the dimension value, this is always calculated in drawing units.

Setting the Text Location To change the text location click on the "Format…" button in the Dimension Styles dialogue box. The Format dialogue box is shown below. By default the horizontal justification is set to "Centred" and the vertical justification to "Above". This means that the dimension text will appear centred above a horizontal dimension line and centred left of a vertical dimension line. To have the text centred within the dimension line, click on the down arrow of the "Vertical Justification" pull-down list to reveal the options and click on "Centered". The illustration changes to reflect your choice. Click on "OK" to return to the Dimension Styles dialogue box. You can see the result of this action by looking at the illustration below. Experiment with the

Horizontal Justification and Vertical Justification

options to see what results they give.

You can also use Text the option in this dialogue box to change the text orientation in aligned dimensions. By default all dimension text is aligned with the dimension. This option allows you to force text to appear horizontal, irrespective of the orientation of the dimension.

You have independent control over dimension text which appears inside and outside of the dimension lines.

The illustration on the left shows a dimension with vertical justification set to "Above" (far left) and to "Centred" (near left).

Setting Text Style and Units Text style and units are both set using the Annotation dialogue box, illustrated below. To set a text style to a dimension you must first have created the style using the Text Style command (Format/Text Style… from the pull-down menu). To assign the text style to a dimension style, click on the "Annotation…" button in the Dimension Styles dialogue box, click on the drop-down list in the "Text" area of the Annotation dialogue and select the required text style from the list. Click on "OK" to return to the Dimension Styles dialogue.

AutoCAD gives you the option to automatically include a unit prefix or suffix with the dimension text. For example, you could set the dimension style in such a way that it created dimensions with "m" to indicate metres after each dimension text. Most usually, dimensions are drawn without units displayed but with a note on the drawing indicating the units used, such as "All dimensions in metres". However, you may have a drawing where


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different units are being used for different elements of the drawing. In such a case it is a good idea to include units to avoid confusion. Remember that the main idea behind dimensioning is to give the maximum amount of information in the clearest and most concise way. To add units to a dimension style, click on the "Annotation…" button in the Dimension Styles dialogue box and enter the required unit character(s) in the "Prefix" and/or "Suffix" edit boxes of the "Primary Units" area of the dialogue box. For example, if you wanted to display metres, you would type "m" in the "Suffix" edit box.

The Dimension Update Command

Toolbar Pull-down Dimension/Update

Keyboard DIM UPDATE

The Dimension Update command is used to apply the current dimension style to existing dimensions. You can use this command to change the style of a dimension. Unlike text styles, dimension styles do not automatically update when the style is changed. The UPDATE command must be used to force dimensions to appear in the current text style.

CommanSequence Command: DIM Dim: UPDATE Select objects: (pick dimension to update) Select objects: (pick more dimensions or to end) Dim: (press the escape key, Esc to return Command: _dimradius

Select arc or circle:

Select an arc or circle. Specify dimension line location or [Mtext /Text /Angle]: Click on the point where

you want the dimension to be.

Fig.2 Radius dimensioning.

Exact measurement of the circle in the figure

is 25 units.

JOGGED command does not exist in the

previous versions. This command enables

you to show dimensions for an arc or circle.

As a difference, it shows the dimensions with

a specific symbol as zigzag line.

Command: _dimjogged

Select arc or circle: Click

on an arc or circle. Specify center location override: Choose center. Specify dimension line location or [Mtext /Text /Angle]: Click on where you want

the dimension to be. Specify jog location:


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Specify the location of the dimension text.

Fig.4 JOGGED dimension.

In the figure above, you can see the example

of showing dimension for circle with JOGGED

command.

DIAMETER It is used to present the radius

dimension with (Ø) symbol.

Command: _dimdiameter

Select arc or circle: Select

. Specify dimension line location or [ Mtext/ Text/ Angle]: pick the location.

Fig.6 Radius dimensioning.

ANGULAR enables you to show the

dimension of angular parts. You can click on

both corners and find the angle

measurement. Of there is no second line,

you can draw a temporary line and make

dimensioning by that.

Command: _dimangular

Select arc, circle, line, or : Click on the an arc, circle, line

or corner. Select second line: Select

the second line. Specify dimension arc line location or [ Mtext/ Text/ Angle]: Click on the

location where you want the dimension to be.

Fig.8 Angular dimensioning.

to the command prompt)

Command: _qdim

Select geometry to dimension: 1 found

(If the entity you want to dimension is a POLYLINE then QDIM will easily handle this. Or you can make mulitple selections for the entities you want to dimension one by one and make multiple dimensioning for them)


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Finally, click on the location where you want the dimension to be.

Fig. 2 If you draw a POLYLINE, you can

place all of the dimensions by only one

click.

If you want, you can select all of the entities

you want to dimension by selecting them

with a selection window and dimension all of

them at once, as well as you can make this

operation one bu one for each entity.

Command: _dimbaseline

It enables you to make dimensioning by

taking the location, which has been

dimensioned last, as reference. First,

dimension a step by LINEAR as shown in

Fig. 4.

Then press Baseline dimensioning. Command

will automatically find the first point and

prompt you to enter the second point. Click

on each of the corners respectively.

Fig.4 BASELINE dimensioning.

Command will also automatically determine

the space between the dimensions. If your

dimensions are mixed up, you can make the

relevant necassary adjustments by the help

of Dimension style settings II

article written by Orhan Toker.

Continue Dimension

This dimensioning type enables you to make

dimensions which are the continuations of

each other. At the first stage, dimension the

first step as LINEAR. Then, choose

CONTINUE dimensioning and choose the

end points.


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Fig. 6 Continuing dimensioning

Command: _qleader

As shown in Fig.2, click on points 1, 2 and 3

respectively. Enter your text and text width.

If you press ENTER once, cursor goes to the

line below, if you press ENTER twice, you

end the operation.

With CENTER MARK command, you can

mark centers of CIRCLE or ARC.

Command: _dimcenter

Select arc or circle: Click

on arc or circle.

You can either put a marking at the center of

the circle as seen in figure or by applying the

settings explained by Orhan’s Dimension

Style Settings 3: Dimension arrows and

symbols article. You can place markings as

seen below.

Fig. 7 Centermark may also be used as a

set of axis.

Let’s enter dimension style settings and then

“Symbols and Arrows” tab. (Fig.2).


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Fig.2 Go to symbols and arrows tab.

Arrowheads

You can define arrowheads for first arrow,

second arrow and dimensioning labels (DIM /

LEADER) , separately for each. When you

choose the first arrowhead, second one will

automatically become the same. But, when

you change the second one, first one will not

change.

Arrow Size

Whatever you enter for this variable, affects

all the three symbols I mentioned before.

Arrowsize can change according to the arrow

type you choose. For example, extensions of

arrow size can be double when you want

architectural cuts, on the contrary half will

look better if you choose point.

Center Mark

Fig.3 Center mark can be the axis lines

at the same time.

You can put center marks into circles or arcs

inside the AutoCAD dimensioning system.

This symbol can be either a short plus sign

(mark), or (lines). You can change the

properties of read area I have marked in

Fig.3. Axis lines will also extend as equal to

this setting.

Arc Length Symbol

Fig.4 AutoCAD puts an arc symbol so

that arc length is does not intervene

with the radius.

For your arc length dimensioning, a small arc

symbol is placed near the dimension. With

this setting, you can determine where this


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symbol will be placed. Our options are in

front of, under and not to put.

Radius, Dimension Jog

Fig.5 Jog

Sometimes we show the radius or diameter

dimension for very large arcs or circles with

a zigzag line. In AutoCAD it is called jog

dimension. The last setting in this tab is jog

angle

Fig.1 Dimensions which has come inside

each other.

Those of you, who know technical drawings,

know that when we are making dimensioning

for small spaces, we should make it from

outside to inside. But things get complicated

when the dimension text does not fit. If you

place it on the sides, it will be mixed up with

the other one. There we go, FIT tab inside

the dimension style settings is for this

matter.

Fig. 2 It is possible to lift the text up

First thing that comes into our minds is

“arrows should remain same, but the

text should go up a little” ( Fig.2 ) Here is

the setting you have to do,

Fig. 3

If you set the “Text Placement” in FIT tab

as seen in Fig.3 then the texts are placed up

by a reference extension. This setting is OK.


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Fig .4 Another solution is to keep the

text always inside.

On the other hand, all of the dimension text

can remain inside as seen in Fig.4. In order

to do this, you must use “Always keep text

between ext. Lines” option from “Fit

Options”. Another point is that, if you use

“Supress arrows if they don’t fit inside

extension lines” there will be no arrows for

the narrow dimension spaces (Fig.5).

Fig. 5 Fit options

One of the most important and unknown

setting for dimensions is “Scale for

dimension features”. By using “Use

overall scale of:” among these options, you

can enlarge or narrow all of the physical

properties of the dimension (like dimension

arrow size, text height etc.) by the amount

of value you enter here. Thus, if you enter 2,

all of the dimension style properties will

double (Of cource except the measured value

).

In this part, there is also a “Scale

dimensions to layout” option. This option

is for those who use LAYOUT. AutoCAD

automatically scales all of the dimensions.

For this reason, we are always suggesting

you to use LAYOUT.

Fig. 6 Overall scale

We also have fine tuning settings. . “Place

text manually” option asks you to place all

of the dimension text during the

dimensioning. We strongly suggest you to

leave this field empty. Our last setting is

“Draw dim line between ext lines”, which

is not to place dimension line in between if

the spacing is very small. This option should

also be left blank.

Fig.7 Fine tunings


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You can change each of these settings in

these tabs, so that you can learn what they

are for.

Fig. 1 The units affect the appearance.

Let’s have look at the unit in Fig.1. The

writing style of this dimensioning has not

been edited and it has directly written on the

measured value. At the first look there are

two unnecessary situations in the

dimensioning. The first thing is the writing

style of 5,000 where the zeros are

unnecessary. The second is the needless

three decimals in 16,405 measured value

(sometimes 1/100 scale can be acceptable)

Let’s eliminate these two situations.

Fig. 2. The unit changes are performed

under the “Primary Units”tab.

When we examine the “Linear Dimension”

section in detail in Primary Units tab we

can solve our problem above and can make

some necessary changes. First of all , we

solve the precision value by adding 00 in

Precision section. The other one can be

solved by check the “Trailing” in “Zero

Suppression” section. “Trailing zero

suppression” means hide the zeros after

commas should be checked. We have

completed the first phase.


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Fig.3. The extra zeros and numbers

were eliminated by the adjustments we

performed.

Now let’s have look at the other items

and see how it works:

Round Off value can be used whenever

requested. For example in architecture 5mm

precision is being used and cm is accepted as

standard unit. Therefore from this time only

0.5 precision after the point is very

important for us. If “Round off” value is

entered as 0.5 then 24.6 will be showed as

25.0 as well as 24.3 will be showed as 24.5.

In other words if the value is greater than

0.5 then it rounds the latter value if not it

rounds the former one.

Prefix and Suffix values are used when you

want extra writing in front or behind of the

values. For example if the suffix value is

entered as mm then mm expression will be

displayed in the screen (25 mm).

Scale Factor is used when you want to

multiply the measure value. For example in

spite of our all warnings you have drawn one

to one means 1/50 (1 m = 2 units) drawing.

If Scale Factor is made as 50 it will give the

measured value in cm. If you make it only in

the Layout portion please click on the mini

table below in order to prevent other values

to be not disturbed.

Fig.4. The unit can be also written.

Fig.1 You can also have AutoCAD to

write the alternative measurement

under the main dimension.

As you know, AutoCAD automatically

measures the distance between the two

points you have chosen and writes it while

you are making the drawing, unless you

specify anything else. Now you will see one

of the benefits, as I had mentioned in my

article Understanding scale concept and


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units in Autocad, of preparing the drawing

one to one, not according to a scale.

Let’s say you are managing one project with

a Japanese originated company and they are

using engineering units but you are using

metric units. So, both sides may have

difficulty in reading the units. You can

resolve this by making a small adjustment in

the dimension style settings. Let’s go to

“Alternate Units” tab in the dimension style

settings.

Fig. 2 When you choose the option that

is marked with red, other settings will

open.

First of all, we should start by marking

“Display alternate units” option. By

marking this option, we have both opened

the alternative settings and activated the

settings. Now, let’s have a look at these

settings.

Unit Format: In this drop down menu, there

are the default unit settings. It is used to

change the variable as architectural,

scientific, engineering settings. Let’s choose

engineering for Japanese.

Precision: Here, you can determine how

much precision you want for the format you

have chosen.

Multiplier for all units: We can roughly say

that it is the ratio of your unit to the

alternative unit, i.e. if 25.4mm = 1”, then

your multiplier will be 0.03937. As I have

told you, the default formats in the drop

down menu I have mentioned above works.

However, for a special unit (for example

fathom :) ) you will have to specify the

multiplier.

Round distances to: Similarly as I

mentioned in my previous articles, you can

of course specify a rounding value. However,

according to the unit system you have

chosen, the rounding values may be a little

different.

Prefix/Suffix: It is same as they are in the

units. Whatever you write here, will come in

front or after the alternative dimension.

Zero Suppression: It is possible not to

write the 0 feet or 0 inch values that are


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remaining at the end of the decimal part of

the alternative unit system.

Fig. 3 Where shall we put the alternative

dimension?

We can set the location where the alternative

dimension will be placed by “Placement”

option. I always prefer to put it below. You

can have this by marking the “Below the

primary value” option.

Fig. 1 Assigning symmetrical tolerance

values.

To achieve this, you must select the format

you like from the “Tolerance Format” pull-

down menu from TOLARENCES tab in

dimension style settings (Fig. 2).

Fig. 2 We can make tolerance assigning,

which we are used to, from basic

tolerance settings.

By using the first option, which is

“Symmetrical”, you can get the tolerance

format as shown in Fig. 1. By using the

other settings, you can change values like

decimal digits after dot (precision), upper

and lower values and text height scale

(scaling for height).

Below, you can find examples for tolerance

formats.

Fig. 3 Tolerance by using deviation

method.


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Fig. 4 Showing tolerances by using

upper and lower limits.

Fig. 5 Basic tolerance (You should put

tolerance beside it by yourself).

:ARRAY COMMAND

The Array command makes multiple copies of selected objects in a rectangular matrix (columns and rows) or a polar (circular) pattern

• RECTANGULAR ARRAY- Arrays the selected object in Rows/ column arrangement.

Now start the Array command.First of all, make sure that the Rectangular Array radio button is selected and that you are looking at the Rectangular Array dialogue box and now follow the steps below:

1. Click the Select objects button. The dialogue box will temporarily disappear enabling you to select the rectangle you just drew. Press the Return button on your keyboard to complete the selection. You are now returned to the dialogue box and the message immediately below the Select Objects button should read "1 objects selected".

2. Enter the number of rows required in the Rows edit box. For this example, enter the value "3". Notice that the schematic preview on the right hand side of the dialogue box updates to reflect the values you are entering.

3. Enter the number of columns required in the Columns edit box. Enter the value "2".


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AUTOCAD 4. Enter the row offset in the Row Offset edit box.

This is the distance DR in the illustration above. Note that tis is not the distance between rows. In this example, our rectangle is 10 units high and we will enter a row offset of 15. The result will be a 5 unit gap between rectangles.

5. Enter the column offset in the Column Offset edit box. The same parameters apply as for the row offset. Enter a value of 25 to give a 5 unit gap between our rectangles.

6. Click on the Preview button. Once again, the dialogue box disappears and the specified array is temporarily drawn so that we can preview it. We are now offered 3 choices. If the array isn't quite right, click the Modify button to return to the Array dialogue box. If you are happy with the array, click the Accept button, the array will be permanently drawn and the command is ended.

You should now have an array that looks similar to the one in the illustration above consisting of 6 rectangles arranged in 3 rows and 2 columns. As you can se, this command is very powerful and can save lots of time if used carefully.

• POLAR ARRAY-

Arrays the selected object in circular arrangement.

You can try this for yourself by drawing another rectangle as described above. This time, though, locate the rectangle in the centre top half of the drawing area. Now, start the Array command, click the Polar Array radio button

and follow the steps below:

1. Click the Select objects button. The dialogue box will temporarily disappear enabling you to select the rectangle you just drew. Press the Return button on your keyboard to complete the selection. You are now returned to the dialogue box and the message immediately below the Select Objects button should read "1 objects selected".

2. Specify the center point for the array. This is the point C in the illustration below. You can do this by entering x and y co-ordinates into the appropriate edit boxes if you know what these values should be. However, this is rarely the case and most often you will want to click the Pick Center Point button to pick a point from the drawing area. Pick a point somewhere below the rectangle you have just drawn.

3. Enter a value for the total number of items. For this example, enter the value "6". Notice that once again, the schematic preview updates to reflect the values you have entered.

4. Make sure that the Rotate items as copied checkbox is checked.

5. Click on the Preview button. Once again, the dialogue box disappears and the specified array is temporarily drawn so that we can preview it. We are now offered 3 choices. If the array isn't quite right, click the Modify button to return to the Array dialogue box. If you are happy with the array, click the Accept button, the array will be permanently drawn and the command is ended.

The array you have just drawn should look something like the one illustrated below, left. Take some time to play around with the other options in the Array dialogue box to see what they can do


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ARRAY-

Modify toolbar >

Pull down menu > Modify > Array

Keyboard ARRAY or AR

ELLIPSE COMMAND- The Ellipse command gives you a number of different creation options. The default option is to pick the two end points of an axis and then a third point to define the eccentricity of the ellipse. After you have mastered the default option, try out the others.

Draw toolbar

Pull down menu >draw > Ellipse

Keyboard ELLIPSE or EL

ARC- The Arc command allows you to draw an arc of a circle. There are numerous ways to define an arc, the default method uses three pick points, a start point, a second point and an end point. Using this method, the drawn arc will start at the first pick point, pass through the second point and end at the third point. Once you have mastered the default method try some of the others. You may, for example need to draw an arc with a specific radius. All of the Arc command options are available from the pull-down menu.

Draw toolbar

Pull down menu > Draw > Arc

Keyboard ARC or A

EXPLODE- The Explode command is used to "explode" single objects back to their constituent parts. In other words, the command is used to return blocks, polylines etc. (which may be composed of a number of component objects) back to their individual component parts. The change has no visible effect

Modify toolbar

Pull down menu > Modify > Explode

Keyboard EXPLODE or X


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AUTOCAD The Dimension Style Manager

Keyboard DDIM or D So now that you have seen what can do - how do you do it? All options are available in the DDIM (Dimension Style Manager) dialog box.

On the left is current style for working with (highlighted in green) and below that is an indicator that the style has overrides.

In this lesson, you will create a new Dimension Style and use it in a drawing. From there, you should try different styles and get familiar with the options. Most companies these days will have a standard style (or set of styles) to use on drawings, but this is a very important tool to know if you want to turn out professional looking drawings.

Start but invoking the DDIM command and press the NEW button to open the small dialog for entering the name of the style you are creating. In this example I used the name "DIMSTYLE 1".

Make sure that "Start with" has "Standard" as its setting. Press the Continue Button when everything is set. This will open the dialog box for settings, so just press OK to close it for now.

Back at the "Dimension Style Manager" dialog box, you will see that the new style you created is listed at the top (left side). To modify it, select the name, then press the modify button. The dialog box opens at you are at the first tab (Lines and Arrows).

As a general rule, I recommend not change much on this tab - especially when you're learning. Set as defaults, the dimensions are sized proportionately, if you change the setting on one parameter, your dimension can look 'off-balance'. For example, you could end up with huge arrows and small text. For the purposes of this lesson, the only thing that will change on this tab is the arrowheads. Select something other than the standard. You'll also see that you can set the colours, but just like regular objects, it's best to leave them set to "Bylayer" - and make sure you have a separate layer for all dimensions.

Go to the second tab (Text).

Start up the Text Styles dialog box by pressing the button with the ... next to the text name. Create a new textstyle using RomanS and a width of 0.8 and call it "DIMTEXT". (For more info, see Lesson 1-8.) Close the Text Styles dialog box. Select DIMTEXT as your text for dimensions as shown.

The great thing about this dialog box is that it shows you a preview of what your changes will do the final dimension in the top right window. In the bottom right, select ISO as the Text Alignment option. Try some other changes to see their effects in the preview, then end with the settings as shown below:


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So far you haven't changed much, but you've seen the options available in just 2 tabs. Click on the next tab to continue.

As a rule, I leave this tab alone. AutoCAD does a good job of placing and fitting dimension where I want them. If I don't agree, I usually just use grips to edit the placement. Click on the next tab (Primary Units) to continue.

In the Primary Units, you find some of the more common parameters that need to be changed. Precision is very important. First off, you usually don't need to show 4 decimal places. If you do show 4 decimals places and send your drawing off to the machinist, you are asking him to manufacture the part to within 1/10000 of a unit - which can be a very expensive mistake. 3 Decimal places is usually enough - or less for rougher jobs.

Also, I have added a couple of other changes; adding leading and trailing zeros and a suffix denoting the units.

Make the changes you see above and check the preview after each change. In this tab, you can also set the overall scale of your dimensions. This can also be done using the DIMSCALE command.

The next tab (alternate units) is used if you want to display two different units in your dimension. For example, you can draw your drawing in imperial inches, then dimension with inches as your primary units and add the alternate units behind. Skip this tab for now and go on to the last tab (Tolerances).

In this example, you will set the tolerances to be +/- .05 units and display them at 80% of the primary units. Sound easy? It is. Look at the image below to see how this is done.

WBLOCK command - a create tool for creating a new file from content in your current open drawing.

Keyboard WBLOCK or W


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Standard toolbar

Pull down menu > Format > Layer

Keyboard LAYER

LAYER- Although AutoCAD provides many shortcuts for working with layers, many of which will be covered later, the Layer command provides the most comprehensive control over layers and layer operations. This command uses a dialogue box. The dialogue box is a tabbed dialogue box and can be modified to show more or less details. This is quite nice because in its simplified form it looks much less intimidating to beginners. The following setions demonstrate how the Layer command can be used to perform many of the most common layer operations.

Creating a New LayerTo create a new layer, click on in the Object Properties toolbar, the Layer & Linetype Properties dialogue box, illustrated below, appears. This is a tabbed dialogue box and can be used to control either layer properties or linetype properties depending upon which tab is selected. The Layer tab is always selected by default. Now click on the "New" button. A new layer called "Layer1" is automatically created in the layer list below layer 0. As you can see from the illustration, the layer name is automatically highlighted for you so that you can give the layer a more meaningful name. When you have entered an appropriate name, press the key to complete the operation. You have now created a new layer and given it a name. Notice that by default it has been assigned the colour white and the linetype "Continuous".

There are a few restrictions to consider when you are naming layers. The most annoying is that you cannot use spaces within layer names. So, for example, the layer name "Tree trunk" is illegal. However, it is common practice to replace the space with either a hyphen or an underscore, both of which are valid layer name characters. So, the layer names "Tree-trunk" and "Tree_trunk" are both acceptable. Some other special characters are also not allowed. If you do use an illegal character, AutoCAD will alert you with the error message box illustrated above. Notice that it very helpfully tells you which characters are legal. Basically, if you stick with letters and numbers you won't experience any problems. In addition to the hyphen and underscore mentioned above, the dollar sign is the only other symbol allowed.

The only other restriction relating to layer names is the number of characters used. Layer names can be between one and thirty-one characters long. This should give you plenty of scope to devise understandable and descriptive names for your layers. It is good drawing practice to name your layers sensibly, bear in mind that other people may have to work with drawings which you create. If you enter a layer name longer that 31 characters, AutoCAD will display


45

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Layers are always listed alphabetically in layer lists, the user has no other way to control the list order. It is worth bearing this in mind when naming your layers. Keep similar object layers together by devising a hierarchical naming structure. For example, if you are drawing a tree symbol which comprises a number of elements, your layer names might be, "Tree_canopy", "Tree_text", "Tree_trunk" etc. This will cause all the Tree layers to be displayed together, see the illustration on the right. This is quite important because in complicated drawings there may be many layers and searching for the right group of layers can waste a lot of time.

Setting Colour and Linetype "ByLayer"

AutoCAD offers two methods of setting the colour and linetype of a drawing object. First of all, colour and linetype can be set ByLayer. In other words, an object will be displayed in the colour and linetype of its layer. For example, if you draw a circle on a layer which you have called "Detail" and you have also set the colour of Detail to blue and the linetype to dashed, then the circle will be displayed in a dashed blue line. When an object takes on the properties of its layer, the colour and linetype are said to be set "ByLayer".

The second method AutoCAD offers is to set the colour and linetype by object. Setting properties by object overrides those set ByLayer. In general it is good drawing practice to set colour and linetype properties ByLayer, this is more efficient and less confusing in the long-run. For example, imagine that you have drawn hundreds of objects on the same layer and have set their colour to green. Later in the

drawing process you decide that these objects should, in fact, be yellow. In order to make the change you would have to use the Properties command and select every one of the objects by picking them. By contrast, if you had set the objects colour to ByLayer, you would only have to change the layer colour from green to yellow and all of the objects would change.

There are times , however, when in is useful to be able to set colour and linetype properties by object. Setting properties by object is covered later in this tutorial. The following sections cover the setting of colour and linetype ByLayer.

Making a Layer the Current Layer

Once you have created some layers you will want to start using them. As indicated above, you can only draw on one layer at a time. In order to draw on a particular layer you must first make it the current layer. As usual with AutoCAD there are a number of alternatives. You could, for example, use the Layer command, Layer... from the Format pull-down or from the Object Properties toolbar. As you have seen previously, this command brings up the Layer & Linetype Properties dialogue box. To

set the current layer, select a layer name from the list and then click on the "Current" button and then click the "OK" button to finish. The selected layer is now the current layer and it's properties are displayed on the Object Properties toolbar.

Most experienced AutoCAD users change the current layer so frequently that the above method starts to seem very long winded. It is much quicker and therefore more efficient to set


46

AUTOCAD the current layer directly from the Object Properties toolbar using the "Layer Control" drop-down list. To set the current layer, click on the down arrow next to the Layer Control window to reveal the layer list. Simply click on the name of the layer you wish to make current. If the layer name is not visible because the list is quite long, scroll down the list until you see it. The drop-down list only displays 10 layers at a time. As a beginner, you may feel that this is quite a lot but a complex and well structured drawing may have 50 or 100 layers.

Turning Layers On and Off

You can turn layers off or on either by using the

Layer command, from the Object Properties toolbar or you can more easily do it using the "Layer Control" list, directly from the Object Properties toolbar. In either case, all you have to do is click on the icon you wish to change. The icons all act as toggles, so if a layer is on, all you need to do is click on the icon and the icon will change to , turning the layer off. And conversely, clicking on changes the icon to and turns the layer back on.

Objects on a layer which is turned off aren't displayed in the drawing window and they won't be plotted. The objects still exist in the drawing; they are just invisible.

If a layer is turned off and you make it the current layer, AutoCAD turns it on. It's possible to turn off the current layer, but this is rarely desirable. To do so causes no harm, but it can be confusing if you don't realise what has happened; new objects you draw are added to the drawing but are not displayed until the layer is again turned on. Each designated layer is turned on (made visible) using the colour number and linetype previously associated with it. If the layer is presently frozen, turning it on is not sufficient to make it display again; you must also thaw the layer (see Freezing and Thawing Layers below).

Renaming a Layer

To rename a layer, start the Layer command by

clicking on the button on the Object

Properties toolbar. When the Layer & Linetype Properties dialogue box appears, click on the "Details>>" button to reveal the layer details. Pick the layer name you wish to change from the layer list. The name appears in the Name text edit box under "Details". Simply edit or retype the name in the edit box and you will see the name change simultaneously in the layer list. You cannot rename layer "0", the deafault layer, nor can you rename a layer called "Defpoints" which AutoCAD creates automatically when you use Dimensions (see Dimensioning). In theory you can also edit a layer name directly from the layer list but I have always found this to be a bit tricky. Notice that you can also change the layer colour and linetype using the "Details" section of the dialogue box.

Deleting a Layer

To delete a layer, start the Layer command, from the Object Properties toolbar to open the Layer & Linetype Properties dialog box. Click the name of the layer to highlight it, click the "Delete" button and then click "OK".

You cannot delete any layer which has objects on it, you cannot, therefore, use this process to delete all of the objects on a particular layer. You cannot delete the current layer, layer "0", layer "Defpoints" or any layers from external references.

To delete a layer, start the Layer command, from the Object Properties toolbar to open the Layer & Linetype Properties dialog box. Click the name of the layer to highlight it, click the "Delete" button and then click "OK".

You cannot delete any layer which has objects on it, you cannot, therefore, use this process to delete all of the objects on a particular layer. You cannot delete the current layer, layer "0", layer "Defpoints" or any layers from external references.


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AUTOCAD

POLY LINE - Polylines differ from lines in that they are more complex objects. A single polyline can be composed of a number of straight-line or arc segments. Polylines can also be given line widths to make them appear solid.

You may be wondering, if Polylines are so useful, why bother using ordinary lines at all? There are a number of answers to this question. The most frequently given answer is that because of their complexity, polylines use up more disk space than the equivalent line. As it is desirable to keep file sizes as small as possible, it is a good idea to use lines rather than polylines unless you have a particular requirement. You will also find, as you work with AutoCAD that lines and polylines are operationally different. Sometimes it is easier to work with polylines for certain tasks and at other times lines are best. You will quickly learn the pros and cons of these two sorts of line when you begin drawing with AutoCAD.

The Polyline or Pline command is similar to the line command except that the resulting object may be composed of a number of segments which form a single object. In addition to the two ends a polyline is said to have vertices (singular vertex) where intermediate line segments join. In practice the Polyline command works in the same way as the Line command allowing you to pick as many points as you like. Again, just hit to end. As with the Line command, you also have the option to automatically close a polyline end to end. To do this, type C to use the close option instead of hitting . Follow the command sequence below to see how this works.

Draw toolbar

Pull down menu > Draw > Polyline

Keyboard POLYLINE or PL

POLYEDIT

Keyboard POLYEDIT ,PEDIT or PE

Command use to transform multiple objects(consist of lines and arcs) into single object.

MULTILINE-

Pull down menu > Draw > Multiline

Keyboard MULTILINE or ML

The Multiline command is used to draw multilines. This process of drawing is pretty much the same as drawing polylines, additional line segments are added to the multiline as points are picked. As with polylines, points can be unpicked with the Undo option and multilines can be closed.

When you start the Multiline command you also have the option to specify the Justification, Scale and Style of the multiline. The Justification option allows you to set the justification to "Top", the default, "Zero" or "Bottom". When justification is set to top, the top of the multiline is drawn through the pick points, as in the illustration below. Zero justification draws the centreline of the multiline through the pick points and Bottom draws the bottom line through the pick points. Justification allows you to control how the multiline is drawn relative to your setting out information. For example, if you are drawing a new road with reference to its centre line, then Zero justification would be appropriate.


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AUTOCAD The Scale option allows you to set a scale factor,

which effectively changes the width of the multiline. The default scale factor is set to 1.0 so to half the width of the multiline, a value of 0.5 would be entered. A value of 2.0 would double the width.

The Style option enables you to set the current multiline style. The default style is called "Standard". This is the only style available unless you have previously created a new style with the Multiline Style command.

ALIGN- Use ALIGN to move, rotate, or scale objects into alignment with other objects. Add source points to the objects you want to align, and add destination points to the objects to which you want the source objects to align. You can add up to three pairs of source and destination points to align an object

Keyboard ALIGN or AL

STRETCH- The Stretch command can be used to move one or more vertices of an object whilst leaving the rest of the object unchanged. In the example below, a rectangle has been stretched by moving one vertex to create an irregular shape.


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AUTOCAD

ISOMETRIC DRAWING

Rctangular snap Isometric snap

The Isometric Snap/Grid mode helps you create 2D isometric images that represent 3D objects.

By setting the Isometric Snap/Grid, you can easily align objects along one of three isometric planes; however, although the isometric drawing appears to be 3D, it is actually a 2D representation. Therefore, you cannot expect to extract 3D distances and areas, display objects from different viewpoints, or remove hidden lines automatically.

TO DRAW ISOMETRIC CIRCLE

1. From the Tools menu, choose Drafting Settings.

2. On the Snap and Grid tab, under Snap Type and Style, turn on the isometric snap and choose OK.

3. From the Draw menu, choose Ellipse Axis, End.

4. Enter i (Isocircle).

5. Specify the center of the circle.

6. Specify the radius or diameter of the circle.

ISOPLANE The isometric plane affects the cursor movement keys only when Snap mode is on and the snap style is Isometric. If the snap style is Isometric, Ortho mode uses the appropriate axis pair even if Snap mode is off. The current isometric plane also determines the orientation of

isometric circles drawn by ELLIPSE. You can cycle through the isometric planes by pressing CTRL+E or F5. LEFT

Selects the left-hand plane, defined by the 90-degree and 150-degree axis pair.

TOP

Selects the top face of the cube, called the top plane, defined by the 30-degree and 150-degree axis pair.

RIGHT

Selects the right-hand plane, defined by the 90-degree and 30-degree axis pair.


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AUTOCAD

THE 3-D CO-ORDINATE SYSTEM

By now you should be very comfortable working your way around the X-Y co-ordinate system. Anyway, here is a quick review. Looking from the plan (top) view, this is what you see to figure out where is positive X and positive Y.

If you were to look at the same picture, but at a slight angle, you would see the third axis. This new axis is called the Z-axis. Imagine that the positive Z-axis is coming towards you out of the monitor

The Z-axis has always been there, lurking in the background, waiting for you.

When you entered points previously, you would enter them in the format: X,Y. By doing this, you let AutoCAD know that in these cases, Z was equal to zero. Entering 4,3 would be the same as entering 4,3,0. Now if you drew a line from the origin (0,0,0) to a point at 4,3,2, you would get a line that goes 4 inches to the right, 3 inches up and 2 inches towards you. You can choose from several

commands that control the 3D Orbit display, projection, and visualization tools. You can access Pan and Zoom options from the 3D Orbit shortcut menu or on the 3D Orbit toolbar. You can also choose to use a perspective or a parallel projection of the view while 3DORBIT is active.

Shade Objects in the 3D Orbit View

Objects in the 3D Orbit view can be shaded to give them a more realistic 3D appearance. You can change the way objects are shaded using the different shading modes, which are also accessible from the 3D Orbit shortcut menu.

Use Visual Aids in the 3D Orbit View

You can choose to display one or more of the visual aids (compass, grid, and UCS icon) in the 3D Orbit view. A check mark is displayed next to the active visual aid option(s). A visual aid that is active when you exit 3DORBIT remains active in the view outside the 3D Orbit view unless SHADEMODE is set to 2D Wireframe.

• Compass. Draws a sphere within the arcball composed of three lines representing the X, Y, and Z axes.

• Grid. Draws an array of lines on a plane parallel to the current X and Y axes, perpendicular to the Z axis. You specify the height of the grid display in the ELEVATION system variable.

Before starting 3DORBIT, you can use the GRID command to set system variables that control the grid display. The number of major grid lines corresponds to the value you set using the Grid Spacing option of GRID, which is stored in the GRIDUNIT system variable. Ten horizontal lines and ten vertical lines are drawn between major lines.

When you zoom in and out of the 3D Orbit view, the number of grid lines changes to give you a clear view of the lines. Fewer lines are drawn as you zoom out. As you zoom in closer, more grid lines are drawn until the number of lines corresponds again to the number set in GRIDUNIT.


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AUTOCAD • UCS Icon. Turns the display of the UCS icon

on and off. If the UCS icon is displayed when you start 3DORBIT, a shaded 3D UCS icon is displayed in the 3D Orbit view. On the 3D UCS icon, the X axis is red, the Y axis is green, and the Z axis is blue or cyan. The UCSICON command also controls the display of the 3D UCS icon.

Use Continuous Orbit

You can click and drag in the 3D Orbit view to start a continuous motion. When you release the pick button on your pointing device, the orbit continues in the direction that you were dragging.

While Continuous Orbit is active, you can change the view by right-clicking in the drawing area and choosing Projection, Shading Modes, Visual Aids, Reset View, or Preset Views from the shortcut menu. You can also turn the front and back clipping planes on and off while Continuous Orbit is active; however, you cannot adjust the clipping planes. If you choose Pan, Zoom, Orbit, or Adjust Clipping Planes from the shortcut menu, Continuous Orbit ends.

VIEWPORT

Viewports are areas that display different views of your model. As you work on the Model tab, you can split the drawing area into one or more adjacent rectangular views known as model viewports. In large or complex drawings, displaying different views reduces the time needed to zoom or pan in a single view. Also, errors you might miss in one view may be apparent in the others.

Viewports created on the Model tab completely fill the drawing area and do not overlap. As you make changes in one viewport, the others are updated simultaneously. Three model viewports are shown in the illustration.

You also can create viewports on a layout tab. You use the viewports you create there for arranging the views of your drawing on a sheet. You can move and resize these viewports, and you also have more control over the display. For example, you can freeze certain layers in one viewport without affecting the others.

SPLIT AND JOIN MODEL VIEWPORTS

The illustrations below show several default viewport configurations

SELECT THE CURRENT VIEWPORT

In AutoCAD, you always work in one viewport at a time. When you use multiple viewports, one of them is the current viewport. When a viewport is current, the cursor is displayed as crosshairs rather than an arrow and the viewport boundary is highlighted. You can change the current viewport at any time except when a viewing command is in progress.

To make a viewport the current viewport, you click inside it or press CTRL+R to cycle through the existing viewports.

To draw a line using two viewports, you start the line in the current viewport, make another viewport current by clicking within it, and then specify the endpoint of the line in the second viewport. In a large drawing, you can use this method to draw a line from a detail in one corner to a detail in a distant corner.

To join two viewports on the Model tab

1. From the View menu, choose Viewports. Then choose Join.

2. Click within the viewport containing the view you want to keep.


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AUTOCAD 3. Click within an adjacent viewport to join it to

the first viewport

EXTRUDE COMMAND

With EXTRUDE, you can create solids by extruding (adding thickness to) selected objects. You can extrude an object along a path, or you can specify a height value and a tapered angle.

Use EXTRUDE to create a solid from a common profile of an object, such as a gear or sprocket. EXTRUDE is particularly useful for objects that contain fillets, chamfers, and other details that might otherwise be difficult to reproduce except in a profile. If you create a profile using lines or arcs, use the Join option of PEDIT to convert them to a single polyline object or make them into a region before you use EXTRUDE.

REGION- A region is a surface created from objects that form a closed shape, known as a loop. The Region command is used to transform objects into regions rather than actually drawing them (i.e. you will need to draw the closed shape or loop first). Once a region is created, there may be little visual difference to the drawing. However, if you set the shade mode to "Flat Shaded", View ShadeFlat Shaded, you will see that the region is, in fact, a surface and not simply an outline. Regions are particularly useful in 3D modeling because they can be extruded

Creating realistic three-dimensional (3D) images helps you visualize your final design much more clearly than you can with wireframe representations. In the wireframe, because all edges and tessellation lines (lines that help visualize curved surfaces) are visible, it's hard to tell whether you're viewing the model from above or

below. The hidden-line image makes it easier to visualize the model because the back faces are not displayed. Shading and rendering can greatly enhance the realism of the image.

Note It is strongly recommended that you have a 3D graphics card if you plan to use Render options, particularly textures and higher quality transparency.

Of the image types, hidden-line images are the simplest. Shading removes hidden lines and assigns flat colors to visible surfaces. Rendering adds and adjusts lights and attaches materials to surfaces to produce realistic effects.


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AUTOCAD

The purpose of this lesson is to look further at the EXTRUDE command. As you saw in Lesson 3-7, it can be used to create a 3D solid from a closed 2D shape. Two other ways you can extrude (which you may have seen as options on the command line) are to taper the extrusion and the extrude a shape along a path. If you need to, you can also combine the two options and extrude along a path while tapering the shape (shown below

One example where you can use extruded paths is to represent pipes in a drawing. You may not use the tapered path option often, but at least it's there.

EXTRUDING ALONG A PATH

Draw a POLYLINE from 0,0 to 120,0 to 120,120 to 240,120 to 240,0 and then press <Enter> to finish the command.

Do a Zoom > Extents to see the polyline and then zoom out a little more. Your line should look like this:

Next you will put a 24 unit radius on all the corners. The easiest way to do this is using the Polyline option of the FILLET command.

Command: F <ENTER> FILLET Current settings: Mode = TRIM, Radius = 0.0000 Select first object or [Polyline/Radius/Trim/mUltiple]: R Specify fillet radius <0.0000>: 24 Select first object or [Polyline/Radius/Trim/mUltiple]: P Select 2D polyline: <SELECT THE POLYLINE> 3 lines were filleted

What you're going to do next is extrude a circle a long the polyline - or to be more accurate, the path of the polyline. This would be one way of drawing pipes in 3D. For this example, you'll draw a pipeline with a diameter of 12 units.

Next draw CIRCLE at the bottom right end of polyline. Use a diameter of 12 (radius of 6). Once you have that, you need to rotate it in 3D. This is covered in the next lesson as well. To do this, you will select the circle, select the axis you want it rotated around and then choose the angle.

Command: ROTATE3D Current positive angle: ANGDIR=counterclockwise ANGBASE=0 Select objects: <SELECT THE CIRCLE> 1 found Select objects: <ENTER> Specify first point on axis or define axis by [Object/Last/View/Xaxis/Yaxis/Zaxis/2points]: X Specify a point on the X axis <0,0,0>: <SELECT THE BOTTOM RIGHT END OF THE POLYLINE - Make sure your Osnaps are on for endpoints> Specify rotation angle or [Reference]: 90 <ENTER>


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AUTOCAD Your circle should have rotated 90 degrees and now you are looking at the side of it so the circle appears to be a line as shown in the image below.

Now comes the easy part. Next you will EXTRUDE the circle along the path of the polyline.

Command: EXT EXTRUDE Current wire frame density: ISOLINES=4 Select objects: <SELECT THE CIRCLE> 1 found Select objects: <ENTER> Specify height of extrusion or [Path]: P Select extrusion path or [Taper angle]: <SELECT THE PLINE>

Note: After the Extrude command, the polyline will still be there. If you need to keep your drawing clean, remember to erase the path if you don't need it any more. To see how it looks, view the object in the SW Isometric view, and use the HIDE command. It should look like this:

This is just one option available with the Extrude command. Try it on other paths and see how it works. You will find that if your circle is too large, it may not be able to be extruded on polylines with tight corners. Any object that can be extruded can

be extruded along a path. A path can be any open object such as lines, arc, polylines, splines, etc.

For more practice, try to created a cord for your lamp (Lesson 3-8) using a Spline as the path. You can also extrude 2 circles along a path (make one one circle smaller) and then subtract the smaller diameter extrusion from the larger to create a hollow pipe.

Use the 3DORBIT command to view it at different angles (Click on the screen, hold the button down and move the cursor around the screen). Try extruding different shapes with various taper angles for more practices.

These options give you a lot of versatility within one command. You may not use these options very often in your everyday drafting, but they're good to know

UCS – USER CO-ORDINATE SYSTEM The user coordinate system (UCS) is a movable coordinate system for coordinate entry, planes of operation, and viewing. Most AutoCAD geometric editing commands are dependent on the location and orientation of the UCS; objects are drawn on the XY plane of the current UCS

SETTING AND USING THE UCS

When working in 3D, it sometimes necessary to change the plane that you are drawing on. For example, if you need to add some detail to the side of a wall, you would want to draw on that plane. It's like taking a sheet of paper up off the floor (WCS) and taping it onto the wall (UCS).

The WCS is the World Co-ordinate System. This is the way that the standard X,Y and Z axis are directed when you begin a new drawing (X to the right, Y pointing up and Z pointing towards you). The UCS is the User Co-ordinate System. This is a ‘redirection' of the WCS based on parameters set

by the AutoCAD user.

There are several ways of doing this, and we'll look at an example here


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AUTOCAD

This is a simple shape drawn on the WCS with one corner located at 0,0,0.

Here is the same object shown a new UCS based on the side of the object, so that you are enabled to draw a rectangle on that side:

Notice that the positive X Axis is now pointing along the side of the house.

Here's how it was changed: You first choose the 3 point option by typing 3 at the prompt. Next you have to pick three points to define the plane. The first point is the new origin. The second point is

where you want the positive X-axis to be positioned. The last point is for the positive Y-Axis.

Command: UCS Current ucs name: *NO NAME* Enter an option [New/Move/orthoGraphic/Prev/Restore/Save/Del/Apply/?/World] <World>: 3 Specify new origin point <0,0,0>: (P1) Specify point on positive portion of X-axis <1.0000,7.0000,0.0000>: (P2) Specify point on positive-Y portion of the UCS XY plane <1.0000,7.0000,0.0000>: (P3)

This is the ‘3-Point' option of the UCS Command. It is one of the most useful, because you control exactly where the new drawing plane will be. You must also be extremely careful when picking the 3 points, or your plane can be shifted and cause some major problems. I would recommend using this method for most of your UCS work - or at least get very comfortable with it before moving on to other methods

.NOTE: Pressing enter immediately after entering the UCS command accepts the default of returning to the WCS.

Here are the other options of the UCS command.

ORIGIN:

Command: UCS Origin/ZAxis/3point/OBject/View/X/Y/Z/Prev/Restore/Save/Del/?/<World>: O Origin point <0,0,0>: <PICK A POINT>

This option moves the UCS based on a newly picked origin point. It does not shift the drawing plane

at all as you only pick one point.

Z-AXIS:

Command: UCS Origin/ZAxis/3point/OBject/View/X/Y/Z/Prev/Restore/Save/Del/?/<World>: ZA Origin point <0,0,0>: Point on positive portion of Z-axis <-8.0000,0.0000,1.0000>:

This choice allows you to pick two points. First you pick the new origin, then you pick a point for the positive Z-Axis. Make sure you type ZA to choose this option.

OBJECT:

Command: UCS Origin/ZAxis/3point/OBject/View/X/Y/Z/Prev/Restore/Save/Del/?/<World>: OB Select object to align UCS:


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AUTOCAD Using this method, you have to pick on a 2D object that is lying on a particular drawing plane. This gets tricky, as you have to be aware how your positive X and Y axes end up.

VIEW:

Command: UCS Origin/ZAxis/3point/OBject/View/X/Y/Z/Prev/Restore/Save/Del/?/<World>: V

By choosing the view option, AutoCAD will automatically reset the UCS to be aligned with your current view, keeping the origin where it was previously located.

X / Y / Z:

Command: UCS Origin/ZAxis/3point/OBject/View/X/Y/Z/Prev/Restore/Save/Del/?/<World>: X Rotation angle about X axis <0>: -90

By selecting either the X, Y or Z options, you need to first pick a point along the axis you have chosen, then provide a rotation angle based on the right hand rule mentioned earlier.

PREVIOUS:

Command: UCS Origin/ZAxis/3point/OBject/View/X/Y/Z/Prev/Restore/Save/Del/?/<World>: P

This option returns you to the last setting you had for the UCS.

Restore/Save/Del/?/

The next options are used in conjunction with each other. You have the option of saving a particular UCS with a name. You can then restore that named UCS or delete if you no longer will be using it. Here are examples of these options:

Command:UCS Origin/ZAxis/3point/OBject/View/X/Y/Z/Prev/Restore/Save/Del/?/<World>: S ?/Desired UCS name: VIEW1

Command:UCS Origin/ZAxis/3point/OBject/View/X/Y/Z/

Prev/Restore/Save/Del/?/<World>: R ?/Name of UCS to restore: VIEW1

Command: UCS Origin/ZAxis/3point/OBject/View/X/Y/Z/Prev/Restore/Save/Del/?/<World>: ? UCS name(s) to list <*>: Current UCS: VIEW1 Saved coordinate systems: VIEW1 Origin = <0.0000,0.0000,0.0000>, X Axis = <1.0000,0.0000,0.0000> Y Axis = <0.0000,1.0000,0.0000>, Z Axis = <0.0000,0.0000,1.0000> Origin/ZAxis/3point/OBject/View/X/Y/Z/Prev/Restore/Save/Del/?/<World>: D UCS name(s) to delete <none>: VIEW1 Deleted 1 UCS name.

This was a series where a view was saved, restored, listed, and then deleted.

Other notes about the UCS:

Be careful when choosing a UCS. Look to the UCS icon and see that it is aligned the way you want it to be. Look for a clean vertical lines if it should be aligned along a vertical plane.

Always be aware of where your UCS is located. Make sure that positive X is where you expect it to be.

Extra Practice: Create this drawing by switching the UCS to the correct plane to draw the roof and skylights. For the geometry, use a combination of extruding and boolean operations to build it


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AUTOCAD

BOOLEAN OPERATION

BOOLEAN OPERATION

First, to explain the funny name : "It was named after George Boole, who first defined an algebraic system of logic in the mid 19th century."

Working in 3D usually involves the use of solid objects. At times you may need to combine multiple parts into one, or remove sections from a solid. AutoCAD has some commands that make this easy for you. These are the boolean operations as well as some other helpful commands for solids editing.:

UNION- Joins two or more solids into creating one based on the total geometry of all

Solidedit toolbar

Keyboard UNION or UNI

SUBTRACT- Subtracts one or more solids from another creating a solid based on the remaining geometry.

Solidedit

Keyboard SUBTRACT or SU

INTERSECT- Creates a single solid from one more solids based on the intersected geometry

Solidedit Toolbar

Keyboard INTERSECT or INT

SLICE- This command does exactly what the name implies. You can slice a 3D solid just like you were using a knife.

toolbar

Keyboard SLICE or SL

POLYGON- The Polygon command can be used to draw any regular polygon from 3 sides up to 1024 sides. This command requires four inputs from the user, the number of sides, a pick point for the centre of the polygon, whether you want the polygon inscribed or circumscribed and then a pick point which determines both the radius of this imaginary circle and the orientation of the polygon.


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AUTOCAD The polygon command creates a closed polyline in the shape of the required polygon.

This command also allows you to define the polygon by entering the length of a side using the Edge option. You can also control the size of the polygon by entering an exact radius for the circle

Pull down menu > Draw > Polygon

Draw toolbar

Keyboard POLYGON or POL


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AUTOCAD

REVOLVE & REVSURF

REVOLVE- Create a Revolved Solid

With REVOLVE, you can create a solid by revolving a closed object about the X or Y axis of the current UCS, using a specified angle. You can also revolve the object about a line, polyline, or two specified points. Similar to EXTRUDE, REVOLVE is useful for objects that contain fillets or other details that would otherwise be difficult to reproduce in a common profile. If you create a profile using lines or arcs that meet a polyline, use the PEDIT Join option to convert them to a single polyline object before you use REVOLVE.

You can use REVOLVE on closed objects such as polylines, polygons, rectangles, circles, ellipses, and regions. You cannot use REVOLVE on 3D objects, objects contained within a block, polylines that have crossing or intersecting segments, or polylines that are not closed.

ISOLINES

Specifies the number of contour lines per surface on objects. Valid integer values are from 0 to 2047.

REVSURF- Use the REVSURF command to create a surface of revolution by rotating a profile of the object about an axis. REVSURF is useful for surfaces with rotational symmetry.

The path curve is swept about the selected axis to define the surface. The path curve defines the N direction of the surface mesh. Selecting a circle or a closed polyline as the path curve closes the mesh in the N direction

The vector from a polyline's first vertex to its last vertex

determines the rotation axis. Any intermediate vertices are ignored. The axis of revolution

determines the M direction of the mesh.

Specify start angle <0>: Enter a value or press ENTER

Specify included angle (+=ccw, -=cw) <360>: Enter a value or press ENTER

Start Angle


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AUTOCAD If set to a nonzero value, begins the surface of revolution at an offset from the generating path curve.

Included Angle

Specifies how far about the axis of revolution the surface extends.

Specifying a start angle begins the surface of revolution at an offset from the generating path curve. The included angle is the distance through which the path curve is swept.

Entering an included angle that is less than a full circle prevents the circle from closing.

The point you use to select the axis of revolution affects the direction of revolution. Each of the surfaces in the examples below was created by specifying a start angle of 0 degrees and an included angle of 90 degrees.

The density of the generated mesh is controlled by the SURFTAB1 and SURFTAB2 system variables. SURFTAB1 specifies the number of tabulation lines that are drawn in the direction of revolution. If the path curve is a line, arc, circle, or spline-fit polyline, SURFTAB2 specifies the number of tabulation lines that are drawn to divide it into equal-sized intervals. If the path curve is a polyline that has not been spline fit, tabulation lines are

drawn at the ends of straight segments, and each arc segment is divided into the number of intervals specified by SURFTAB2.

SPLINE

Pull down menu > Draw > Spline

Draw toolbar

Keyboard SPLINE or SP

The Spline command creates a type of spline known as a nonuniform rational B-spline, NURBS for short. A spline is a smooth curve that is fitted along a number of control points. The Fit Tolerance option can be used to control how closely the spline conforms to the control points. A low tolerance value causes the spline to form close to the control points. A tolerance of 0 (zero) forces the spline to pass through the control points. The illustration on the right shows the effect of different tolerance values on a spline that is defined using the same four control points, P1, P2, P3 and P4.

Splines can be edited after they have been created using the SPLINEDIT command, Modify Object Spline from the pull-down menu. Using this command, you can change the tolerance, add more control points move control points and close splines, amongst other things. However, if you just want to move spline control points, it is best to use grips


61

AUTOCAD PRIMITIVE SOLIDS

What is a Primitive Solid?

A primitive solid is a ‘building block' that you can use to work with in 3D. Rather than extruding or revolving an object, AutoCAD has some basic 3D shape commands at your disposal. From these basic primitives, you can start building your 3D models. In many cases, you get the same result from drawing circles and rectangles and then extruding them, but doing it one command is generally faster. Using these with Boolean operations can be a very effective way of drawing in 3D. There are 6 six different shapes that you can choose from:

You can use primitives to either begin building a model, or it can even be a finished object on its own. Many of these commands are similar to 2D commands, except with an extra co-ordinate in the Z axis. Here is a summary of working with these commands.

You can use BOX to create a solid box. The base of the box is always parallel to the XY plane of the current UCS.

The RECTANG or PLINE command creates a rectangle or closed polyline from which you can create a box using EXTRUDE. The 3D command creates a box shape defined by surfaces only.

To create a truncated cone or a cone that requires a specific angle to define its sides, draw a 2D circle and then use EXTRUDE to taper the circle at an angle along the Z axis. To complete the truncation, you can subtract a box from the tip of the cone with the SUBTRACT command. CIRCLE creates a circle from which you can create a cone using EXTRUDE with its Taper option. The 3D command creates a conical shape defined by surfaces only.

Create a Solid Cylinder

You can use CYLINDER to create a solid cylinder with a circular or an elliptical base. The base of the cylinder lies on the XY plane of the current UCS.

If you want to construct a cylinder with special detail, such as grooves along its sides, create a 2D profile of its base with a closed PLINE and use EXTRUDE to define its height along the Z axis. CIRCLE creates a circle from which you can create a cylinder using EXTRUDE

To create a dome or dish, combine a sphere with a box and use SUBTRACT. If you want to create a spherical object that has additional detail, create a 2D profile and use REVOLVE to define a rotation angle about the Z


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AUTOCAD axis. The 3D command creates a spherical shape defined by surfaces only.

Create a Solid Torus

You can use TORUS to create a ring-shaped solid similar to the inner tube of a tire. The torus is parallel to and bisected by the XY plane of the current UCS.

To create a lemon-shaped solid, use a negative torus radius and a positive number of greater magnitude for the tube radius. For example, if the torus radius is –2.0, the tube radius must be greater than 2.0.

A torus may be self-intersecting. A self-intersecting torus has no center hole because the radius of the tube is greater than the radius of the torus.

The 3D command creates a toroidal shape defined by surfaces only

Create a Solid Wedge

You can use WEDGE to create a solid wedge. The base of the wedge is parallel to the XY plane of the current UCS with the sloped face opposite the first corner. Its height, which can be positive or negative, is parallel to the Z axis.


63

AUTOCAD

SOLID EDITING

With SOLIDEDIT, you can edit solid objects by extruding, moving, rotating, offsetting, tapering, copying, coloring, separating, shelling, cleaning, checking, or deleting faces and edges

Face

Edits 3D solid faces by extruding, moving, rotating, offsetting, tapering, deleting, copying, or changing the color of the selected faces.

Enter a face editing option [Extrude/Move/Rotate/Offset/Taper/Delete/Copy/coLor/Undo/eXit] <eXit>: Enter an option or press ENTER

Extrude

Extrudes selected planar faces of a 3D solid object to a specified height or along a path. You can select multiple faces at one time.

Select faces or [Undo/Remove]: Select one or more faces or enter an option

Select faces or [Undo/Remove/ALL]: Select one or more faces or enter an option

Undo

Cancels the selection of the faces you added most recently to the selection set. AutoCAD then displays the previous prompt. If all faces have been removed, AutoCAD prompts as follows:

Face selection has been completely undone

Remove

Removes previously selected faces from the selection set. AutoCAD then displays the following prompt.

Remove faces or [Undo/Add/ALL]: Select one or more faces (1), enter an option, or press ENTER

Undo

Cancels the selection of the faces you removed most recently from the selection set. AutoCAD then displays the previous prompt. If no faces are currently selected, AutoCAD prompts as follows:

Face selection has been completely undone

ADD

Adds faces to the selection set.

Select faces or [Undo/Remove/ALL]: Select one or more faces (1) or select an option

• Undo: Cancels selection of the faces you added most recently to the selection set. AutoCAD then displays the previous prompt.

• Remove: Removes previously selected faces. AutoCAD then displays the previous prompt.

• All: Selects all faces and adds them to the selection set. AutoCAD then displays the previous prompt.

All


64

AUTOCAD Selects all faces and adds them to the selection set.

All

Selects all faces and adds them to the selection set.

After you select faces or choose an option, AutoCAD prompts as follows:

Select faces or [Undo/Remove/ALL]: Select one or more faces (1), enter an option, or press ENTER

Specify height of extrusion or [Path]: Specify a distance or enter p

Height of Extrusion

Sets the direction and height of the extrusion. Entering a positive value extrudes the face in the direction of its normal. Entering a negative value extrudes the face in the direction opposite to its normal.

Specify angle of taper for extrusion <0>: Specify an angle between –90 and +90 degrees or press ENTER

Tapering the selected face with a positive angle tapers the face in, and a negative angle tapers the face out. The default angle, 0, extrudes the face perpendicular to its plane. All selected faces in the selection set are tapered to the same value. If you specify a large taper angle or height, you can cause the face to taper to a point before it reaches the extrusion height.

Path

Sets a path for the extrusion path based on a specified line or curve. All the profiles of the selected face are extruded along the chosen path to create the extrusion.

Select extrusion path: Use an object selection method

Lines, circles, arcs, ellipses, elliptical arcs, polylines, or splines can be paths. The path should not lie on the same plane as the face, nor should it have areas of high curvature.

The extruded face starts from the plane of the profile and ends on a plane perpendicular to the path at the path's endpoint. One of the endpoints of the path should be on the plane of the profile; if not, AutoCAD moves the path to the center of the profile.

If the path is a spline, the path should be perpendicular to the plane of the profile and at one of the endpoints of the path. If not, AutoCAD rotates the profile to be perpendicular to the spline path. If one of the endpoints of the spline is on the plane of the face, AutoCAD


65

AUTOCAD rotates the face about the point; otherwise, AutoCAD moves the spline path to the center of the profile and rotates the profiles about its center.

If the path contains segments that are not tangent, AutoCAD extrudes the object along each segment and then miters the joint along the plane, bisecting the angle formed by the segments. If the path is closed, the profile lies on the miter plane. This allows the start and end sections of the solid to match up. If the profile is not on the miter plane, AutoCAD rotates the path until it is on the miter plane.

Move

Moves the selected face on a 3D solid object to a specified height or distance. You can select multiple faces at one time.


The descriptions of the Undo, Remove, Add, and All options match the descriptions of the corresponding options under Extrude. After you select faces or enter an option, AutoCAD prompts as follows:

Select faces or [Undo/Remove/ALL]: Select one or more faces (1), enter an option, or press ENTER

Specify a base point or displacement: Specify a base point (2)

Specify a second point of displacement: Specify a point (3) or press ENTER

The two points you specify define a displacement vector that indicates how far AutoCAD moves the selected face and in what direction. AutoCAD uses the first point as a base point and places a single copy relative to the base point. If you specify a single point, usually entered as a coordinate, and then press ENTER, AutoCAD uses the coordinate as the new location.

Rotate

Rotates one or more faces or a collection of features on a solid about a specified axis.


The descriptions of the Undo, Remove, Add, and All options match the descriptions of the corresponding options under Extrude. After you select faces or enter an option, AutoCAD prompts as follows:

Select faces or [Undo/Remove/ALL]: Select one or more faces, enter an option, or press ENTER

Specify an axis point or [Axis by object/View/Xaxis/Yaxis/Zaxis] <2points>: Enter an option, specify a point, or press ENTER

Axis Point, 2 Points

Use two points to define the axis of rotation. Pressing ENTER at the main Rotate prompt displays the following prompts. Specifying a point at the main prompt skips the prompt for the first point.

Specify the first point on the rotation axis: Specify a point (1)

Specify the second point on the rotation axis: Specify a point (2)

Specify a rotation angle or [Reference]: Specify an angle or enter r

Rotation Angle

Rotates the object about the selected axis the specified amount from the current orientation.

Reference


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AUTOCAD Specifies the reference angle and the new angle.

Specify the reference (starting) angle <0>: Specify the starting angle

Specify the ending angle: Specify the ending angle

The difference between the starting angle and the ending angle is the computed rotation angle.

Axis by Object

Aligns the axis of rotation with an existing object. You can select the following objects:

• Line: Aligns the axis with the selected line.

• Circle: Aligns with the 3D axis of the circle (perpendicular to the plane of the circle and passing through the center of the circle).

• Arc: Aligns with the 3D axis of the arc (perpendicular to the plane of the arc and passing through the center of the arc).

• Ellipse: Aligns with the 3D axis of the ellipse (perpendicular to the plane of the ellipse and passing through the center of the ellipse).

• 2D polyline: Aligns with the 3D axis formed by the polyline's start points and endpoints.

• 3D polyline: Aligns with the 3D axis formed by the polyline's start points and endpoints.

• LW polyline: Aligns with the 3D axis formed by the polyline's start points and endpoints.

• Spline: Aligns with the 3D axis formed by the spline's start points and endpoints.

Select a curve to be used for the axis: Use an object selection method

Specify a rotation angle or [Reference]: Specify an angle or enter r

Rotation Angle

Rotates the object about the selected axis the specified amount from the current orientation.

Reference

Specifies the reference angle and the new angle.

Specify the reference (starting) angle <0>: Specify the starting angle

Specify the ending angle: Specify the ending angle

The difference between the starting angle and the ending angle is the computed rotation angle.

LOFT COMMAND

Fig. 1

In first example, we will create the 3-dimensional

entity shown on the right side by dragging 3

circles and 1 square along the path with red color.

Actually, dictionary meaning of LOFT is attic and

LOFTING means to throw something into air. If

you imagine an attic carefully, you will notice that

it is created by dragging a triangle along a

rectangular plan. LOFT command in AutoCAD

works the same way. It creates a 3-dimensional

entity by dragging a number of sections over a

certain path. However, there are certain rules

while drawing:

1. Entities that make up the sections must

form closed surfaces. These entities can

be arcs, elliptical arcs, ellipses, circles, 2D

polylines and 2D splines.

2. Entities that make up section must be

chosen at a definite number.


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AUTOCAD

3. Drawing that makes up the path can be

either a closed or open route. Line, arc,

elliptical arc, spline, ellipse, helix, circle, 2

or 3-dimensional polyline can be used to

draw the path. If more than one main

entity will be used (arc, line, elliptical

arc), then they must be aligned from end

to end and they must be combined into

one polyline by using PEDIT command.

4. If sections will be dragged along guide

lines as shown in Fig. 2, then guide lines

must be again made up of polylines

and/or splines. Guide lines cannot be

closed routes.

Fig.2

The most basic form of LOFT command is to

create a solid by selecting two number of closed

curves.

Start the command and select the two circles one

of which is on top of other. First select the one on

top and then the other one.

Command: _loft Select cross sections in lofting order: 1 found Select cross sections in lofting order: 1 found, 2

total Select cross sections in lofting order: Enter an option [Guides/Path/Cross sections only] <Cross sections only>: C

Pass the last option by pressing ENTER.

Fig.3

You will obtain ‘Loft settings’ window that is

shown in Fig. 3. The options that can be seen in

this window have preview option and your entity

will be updated as you change the settings here.

In Fig. 4, I tried to give examples for some

options.


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AUTOCAD

Fig.4

In this first example, we combined two closed

curves (here what we call them the cro<ss

section curves) by using various options. When

we come to the ‘Guides’ and ‘Path’ options of

LOFT command:

Fig.5

This example that is shown in AutoCAD help files

shows how the example starting and end cross-

section are LOFTed by using aiding curves

(Guides). Make sure that, while drawing these

aiding curves, they must definitely intersect the

curved that you are going to LOFT and the

starting and end points should be exactly on the

curve.

Fig.6

In Fig. 6, I made LOFT by using PATH option.

Fig.7

In Fig. 7, you can see that 4 number of curves

were combined by using ‘Smooth Fit’ and

‘closed’ options.

Fig.8 ‘Normal to all cross sections’


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AUTOCAD

As you can see, there are various options for

LOFT command, however their usage is quite

hard.

HELIX AND SWEEP COMMAND

In this article, I will explain how to draw a basic

screw. As I will focus on HELIX and SWEEP

commands, I will not draw the screw head and

thread end according to rules. First of all, let’s

take a look at the final drawing that we would like

to accomplish:

Fig. 1

In this drawing, you can see as 10×20 screw.

When starting drawing, I created one single

thread spacing according to ISO standards (Fig.

2).

Fig. 2

Section that is in orange color has a triangle in

the base that has dimensions of 1.5 mm and 60

degree internal angles. We will FILLET the top of

this triangle with 0.217 mm radius, and we are

rounding roots of screw with the same radius as

another triangle will come beside it. Then we

obtain the section as shown in figure. By

combining entities that make up this section by

using PEDIT command, we obtain a closed

POLYLINE. After this step, we will create the helix

along which we will sweep this section.


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AUTOCAD

Fig. 3

In order to draw the helix that is shown in Fig. 3,

it will be better to draw the base square that is

shown in Fig. 4.

Fig. 4

After drawing the square with 7.4 x 7.4

dimensions, let’s move on to HELIX command:

Command: HELIX Specify center point of base: (

center of square ) Specify base radius or [Diameter]: ( at this point, select the

position marked with cross ) Specify top radius or [Diameter] <3.7000>: ( enter ) Specify helix height or [Axis endpoint/Turns/turn Height/tWist] <20.0000>: h Specify distance between turns: 1.5001 ( thread size spacing ) Specify helix height or [Axis endpoint/ Turns/ turn Height/ tWist]: 21

When you enter command, AutoCAD will prompt

the center of helix. Select the center of square. In

next step, it asks the base radius of helix. This

question is critical, because, if you specify the

radius with cursor, then point that you select will

also be the starting point. For this reason, it is

better to select the mid points of edges of square.

Because, it will be easier to align the screw thread

that we prepare to the starting point by this way.

Next question is the top radius of our helix. We

will enter 3.7 in the same manner. After entering

these values, here comes the most important

parameters of the command. Among these

options, there are the axis end point, number of

turns, thread size spacing and turning direction.

As the thread size spacing is important for us,

let’s select < H > and ‘Specify distance between

turns’ prompt will come. Let’s enter 1.5001 which

is the thread size spacing. Here, we are specifying

1/10,000 times the required. Reason is that, in

SWEEP command it is not permitted to touch for

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Finally, let’s enter height of our helix as 21. We

will cut 1mm of it while we are adjusting the end.

Fig. 5

In next step, we will prepare the outer section

surface perpendicular to starting point of helix. In

order to do this, you can use ROTATE command

once and 3DROTATE once more (Fig. 6).

Fig. 6

After doing this, let’s carry the middle point of

base to the section surface so that this starting

point will come correspond to starting point of

helix. Next step is to make the spiral by using

SWEEP command.

Command: SWEEP Select objects to sweep: ( orange

section surface) 1 found Select sweep path or [Alignment/ Base point/ Scale/ Twist]: ( helix )

SWEEP command works quite simply. First, we

select the section to be sweeped than the path

over which the section will be sweeped along

(helix). As our threads are formed now, we can

draw a cylinder with R=3.75mm and H=20mm in

the center of this entity and then combine these

two shaped by using UNION command. After that,

we can draw a hexagonal with 4mm height at the

base and combine it with the previous entity by

using UNION command (Fig. 7).

Fig. 7

Finally, slice the end by using SLICE command


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AUTOCAD

RENDERING

MATERIALS AND RENDERING

Fig. 1

You can see the control panel in Fig. 1.

There is the list of defined materials on the

upper part of panel, and there is a small

menu under it. There are material

templates, light properties, texture

properties and opacity and bump map

properties on the lower part.

In this article, we will first see how to

create a simple material. To create a new

material, we are using ‘Create New

Material’ in the small menu. In this first

article, we will create a blue plastic

material, let’s name the material as ‘Blue

Plastic’ New material will immediately

appear in the list. The most important

property of render material is light they

reflect. It is same in real life, different

materials also reflect light differently.

During RENDER, we call this property

‘diffuse’. Our material is created as gray

by default. But as we want it to be blue,

then we should click on the color box and

select a soft blue (Fig. 2).

Fig. 2

Even now, we already have a half matte

blue. Let’s draw a cube on screen and

assign this material to it. After assigning is

complete, then we get what is shown in

Fig3


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AUTOCAD

Fig. 3

Here, we can see a slight reflection. The

reason for that is ‘Shininess’ property in

light settings is adjusted to 50%. As

shininess property decreases, light

becomes smoother and is diffused over a

larger area. Controversially, as shininess

increases, then light will be reflected from

a very small area and more sharply just

like it does from a billiards ball. You can

change shininess and observe the effects

on screen. ( You should set view property

to REALISTIC from DASHBOARD ). Up to

now, we have learned about the color and

shininess properties of material. After

adjusting shininess properties then we

should make RENDER to see the exact

results of our settings. First of all, let’s

draw a surface under the cube and assign

the preset checkered material to it. By this

way, we can see the result more easily. If

you know how to do it, then you can also

add a light to the scene. I will talk about

lights in another article. As the scene is

ready, let’s set shininess property of the

new material to 70%, and ‘Refraction’

value to 1.75. By using this combination,

our material will be shiny enough to reflect

light (Fig. 4).

Fig. 4

As you can see, only by setting there

properties ( diffuse, shininess, refraction ),

we obtained a shiny material just like a

billiards ball. The fourth property ‘Self

illumination’ is used to create materials

which disperse light by themselves, i.e. a

light spreading sphere. However, in real

life, such a material must be transparent

and a light source is inserted into a sphere

that is covered with this material.

However, in textures that are created by

computers, it will create better effects to

combine a light source with a self

illuminatiosn effect (Fig. 5).


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AUTOCAD

Fig. 5

Even though the subject of this article was

plastic material, let me talk about

transparency affect a little bit also. If we

change ‘Opacity’ ( transparency ) property

in material control panel in between 20%

and 0%, then we start to visualize

transparency effect (Fig. 6, 20%). You can

also see that by changing opacity, color of

the shadow also changes.

Fig. 6

In second part of our article series, we will

explain how to create a TEXTURED

material. A typical textured material is

shown in Fig. 1.

Fig. 1

Texture files can be created in JPG, TIFF,

TGA, BMP or PNG formats. However, most

economical one regarding files size is JPG.

There are some certain points that you

should take into account while creating

texture pictures:

1. Texture should be able to repeat

itself.

2. Size of texture picture as of

number of pixels.

3. Color calibration of our own screen.

1) Texture repetition : The most

important property of textures is that they

can repeat themselves over the surface

that they cover. Otherwise, if we cover a

relatively large area with a small texture,

then we obtain a blurry and undesirable

picture. This can be explained best by

windows wallpaper example. Even though

some of the wallpapers are two percent of

the whole screen, by using TILE option we

can see that our desktop is covered with

very nice textures. Preparing such a

texture needs a lot of efforts. Especially 3/8/2015 POWER SKILLS TECHNICAL CENTER www.powerskillsonline.com

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AUTOCAD

when four edges coincide, texture lines

must follow each other (Fig. 2).

Fig. 2

Texture picture shown in Fig. 2 is made up

of combination of two of pictures that is

shown in Fig. 1 side by side. Even though

it is a perfect example for texture

continuity, this is not enough for all only by

itself. It is also required for color saturation

and brightness level at the edges to be

equal, so that there will not be any waving

effect.

2) Size of Texture picture as number

of pixels: If the texture picture is specially

prepared for one project, then in order to

obtain the best results, it should have the

same size with the size seen in render (Fig.

3).

Fig. 3

In Fig. 3, ideal size for the texture picture

is 200×120 pixels. However, texture

materials are generally prepared for

general purposes and as I described in 1.

item, they should be repetitive. For a

repeatable texture, approximately

200×200 pixel size is ideal.

3) Monitor color calibration : Most of

you are not using professional monitors.

For this reason, colors that you see in you

monitor may not be real colors. If you add

the color mistakes due to your scanner,

textures that you have prepared may not

look the same as you desire in other

computers. For this aspect, you should pay

attention to keep color settings of your

monitor and scanner as good as possible

and as close as possible to real colors.

As our texture picture is ready, than we

can immediately use it inside a material

definition. Let’s create a new material from

Material control panel with name of

“CHERRY”. After this, select JPG file (in

my example FFE2.jpg ) that we prepare as

material shown in Fig. 4, as ‘Texture

Map’.

Fig. 4


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AUTOCAD

After making the selection by using

‘Select…’ button, you will see that name

of the button is changed as the texture file

name. There is a texture setting just on

the right side of the button. By using this

icon, we can access settings window by

using this icon (Fig. 5).

Fig. 5

There are the settings for repetition and

scaling in ‘Bitmap Scale’ group. If your

texture is prepared for a single drawing (

painting, wallpaper etc. ), then you can use

‘Fit to object’ option. Size of texture

picture as of pixel dimensions is important

at this stage. You should take into

consideration the area of surface that will

be covered. Beside this selection, you can

also set the number of repetitions in U and

V ( X, Y ) directions. By this way, you can

have the texture picture to be placed by

NxN times over the relevant surface.

Fig. 6

Our other option is to scale our texture.

We must use ‘Tiled’ ( repeated ) option

while scaling. You should pay attention for

scaling unit and drawing unit to be the

same. After these settings, values that we

write in width and height areas will

determine reparation spacings. For

example, a repetition is foreseen with 45

cm intervals.

Offset and Rotation : On the lowest part

of screen (Fig. 7), you can set how much

the texture will be offset in U and V

directions and how many degrees it will be

rotated according to the surface.

Fig. 7


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AUTOCAD

Creating Render Material in AutoCAD : Mapping

When a texture material is assigned to a

surface or a solid entity, then according to

the shape of the entity, AutoCAD

automatically covers it with that texture

material. However, thing may not work out

as we expect all the times and AutoCAD

may make some mistakes; or we may

have some special demands.

When we discussed about material

definitions, we described about tile

property. This property is distributed to all

of the surfaces equally in standard

applications. When mapping is applied to

any material, mapping area will be the

area that is taken as basis for material.

Accordingly, if the mapping area is larger

than the surface to be covered, only part of

the mapping area that covers the entity

will be used; otherwise, whole mapping

area will be used so that it will be

repeated. When expressions are explained

in words it may be a little confusing. So, it

is better explained by an example like

covering a cylinder, cube or sphere by

using a typical woodwork ( with thick, clear

veins). The way woodworks look is

independent from shape, when they are

massive. However, if we cover these

entities, then the texture will take the

shape of them. That’s what mapping is.

Now, let’s continue with an example. There

are 4 different kinds of mapping in

AutoCAD:

1. Plannar mapping

2. Box mapping

3. Spherical mapping

4. Cylindirical mapping

It is obvious what they do, when you look

at their names. Now, let’s examine them

closely one by one:

1. Plannar Mapping :

Fig. 1

As it can be understood from its name, it is

assigned to planar surfaces. It can also be

assigned to other forms in order to get

massive effect. Mapping menu is included

inside the render menu ( Fig. 2).


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AUTOCAD

Fig. 2

Due to the fact that mapping is applied to

entities, you will have to select an entity

and it will start working on an appropriate

mapping as soon as you select one ( Fig.

3).

Fig. 3

Blue triangles that are on the corners are

used for changing dimensions and shapes.

It is similar to STRETCH command. Green,

red and blue stripes ( blue stripe is seen in

drawing as line ) are used for rotating axis.

When we take a look at command line in

this editing mode, then we can see

mapping sub-menu:

Accept the mapping or [Move/ Rotate/ reseT/ sWitch mapping mode]:

By pressing enter, you can accept settings.

MOVE and ROTATE does the work that we

already know. We can use MOVE option if

we don’t want to start from the corner of

the texture; it is especially useful for

paving floor tiles. RESET returns all of the

values to their default values. And, ‘sWitch

to mapping mode’ is used for accessing

one upper menu:

Select an option [Box/ Planar/ Spherical/ Cylindrical/ copY mapping to/ Reset mapping]:

This is actually the first menu (

MATERIALMAP ) that comes up when you

first enter the command. You can copy

mapping settings of one entity to another

by using ‘copY mapping to’ or you can

delete a mapping by using ‘Reset’.

2. Box Mapping :

Fig. 4

In Fig. 4, you can see that box mapping is

assigned to a cube shaped entity. Similarly

as before, the blue triangle and colored

stripes are waiting for to be used. If

spherical mapping is assigned to the same


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entity, then it will look like that is shown in

Fig. 5.

Fig. 5

In order for you to see the difference, I am

giving this example.

3. Spherical Mapping:

Fig. 6

Modifications that can be made by using

spherical mapping are only limited to

ROTATE. This command defines the polar

of cube. In figure, you can see the state of

texture material during and after editing.

4. Cylindirical mapping:

Fig. 7

In Fig. 7, entity that is on the left side is

shown by using cylindrical mapping and

the one on the right is shown by using

planar mapping. As it can be seen on the

entity that is on right side in figure, texture

is being rendered along the cylinder

Creating Render Materials in AutoCAD : Lights

Lights are the most important elements of

scenes as they are so in real life either.

You might have crashed into a well cleaned

glass as you did not notice it. Same glass

can be noticeable in different light

conditions. For this reason, it is very

important to use lights. Uses of lights in

scenes require professional knowledge and

artistic experience. Please note that, during

this article, I will use the word scene for

the view that we will render. I also would

like to mention that I don’t have expertise

for use of lights professionally, and I will

explain the use of lights only in the

technical manner how to place lights into

the scenes in AutoCAD.


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AUTOCAD

Fig. 1-Scene without lights

As there are no lights used in Fig. 1, you

see the painted scene only. During this

article, I will use different lights on the

same scene , so that we will be able to the

differences all together.

1) Sun light: In order to access this light

you have to use ‘Sun Properties’ from

render menu ( Fig. 2), or

SUNPROPERTIES command from

command line.

Fig. 2

As we use this command, a tool panel that

is used to define properties of sun will open

up (Fig. 3).

Fig. 3

If we make ‘Status = On’ under ‘General’

title, then sun properties will change our

scene. In AutoCAD 2007, there is a

calculator for direction of sun ( azimuth ).

This calculator allows you to select the

area by using the lens icon which is just

near ‘Geographic Location’ title. By

making this selection; direction, intensity

and softness of sun is automatically

adjusted according to your current

location, date and time. Here is the result:


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Fig. 4 – Sun light

2) Distant light: This light, which creates

an effect very similar to sun light, can also

be used as sun light. It is in form of light

rays that are parallel to each other and are

coming from same direction. Even though

result is same, shadows are sharper ( Fig.

5).

Fig. 5 - Distant Light

3) Point light: You can think of it as a

ceiling light that has no visor. It is very

suitable for closed areas. It can create

sharp or smooth shadows. Intensity of

these lights can be adjusted. I will explain

about the light settings in detail, for now,

let’s see the result (Fig. 6):

Fig. 6 - Point Light

4) Spot light: They are projection type of

lights that we generally see in theatres and

cinemas. As there is no direction for the

spot light, an insertion point and a target

point must be selected for spot. Besides,

conical angle of strong light ( hotspot ) and

soft light ( fallof ) must be adjusted. When

we select spot lights symbol, two conics

and 4 triangles that show directions will

come up. You can make changes by using

these triangles (Fig. 7).

Fig. 7 – Fall of and Hotspot Settings


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Result of render is given in Fig. 8.

Fig. 8 - Spot Light

As you can also see from the shadow that

falls on the wall, spot light has a visor an

this is generally used for effects.

Light Settings:

Fig. 9

By using ‘Light List’ (Fig. 9) command in

Render menu, you can access the lights list

as shown in Fig. 10.

Fig. 10 – Lights List

When you select a light from lights list and

open ‘Properties’ panel, then all of the

properties related to the selected light is

listed and you can change light settings

from here. In this article, I will only explain

general settings for lights.

Name: This is the only place for you to

change name of your light. In order to

remember the locations of lights, you have

to write appropriate names.

On/Off Status: You can turn on/off your

light from here.

Shadows: Here, you can determine

whether your light will drop shadow or not.

If you are using more than one light, than

you might want some of the lights not to

drop shadow. 3/8/2015 POWER SKILLS TECHNICAL CENTER www.powerskillsonline.com

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Intensity factor: You can set the strength

of lights from here. Values between 0-1

means weakening, values larger than 1

means more lightning. For more

professional people, there is ‘Attenuation’

(turning down light) options. It gives effect

of paper, deflector etc. that has been

placed in front of camera.

One of the more interesting aspects of working in 3-D is that you can visualize what your design will look like. You have so far used the hide and shade commands to give you some idea towards how the final piece will look. The next step is to learn about the RENDER command. This command is the most powerful one for viewing your objects. Using render, you are able to add realistic lighting and materials to get the most realistic view of what you're designing.

You can render objects that don't have materials applied to them, but it won't look as realistic as if you have material added.

The first two blocks shown here are examples of the usual wire-frame view before and after the HIDE command.

These two blocks show how the render command can show the object two ways. The block on the left was rendered without a material applied, while the one on the right has a white ash material applied

Applying the materials is a relatively easy process, getting them to look exactly the way you want them to can be a skill in itself. Once the materials are added, getting the lights and shadows to look realistic is another task that many people prefer to complete in a program other than AutoCAD.

Follow these steps to get an basic, accurate rendering:

Draw the object using solids or surfaces

Apply the materials Render the scene

Once your objects are drawn, you have to decide which materials you want to use. AutoCAD comes with a basic materials library that you can use to apply to your

objects.

Later lessons will teach you how to create new materials and map them to objects. This lesson is designed to allow you to quickly and easily apply materials to your objects.

Start by drawing a basic cube 20x20x20 - this will be your object for testing materials. Go to the Tools Menu and select Tools > Workspaces > 3D Modelling. You will see that two new palettes are added. Close the one on the right for drawing and leave the one that contains a list of materials.

Now that you have your object (the cube) and a list of materials, you're ready to go.

To add a material to the cube, click on the icon of the material you want to use. Move


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AUTOCAD your cursor into the drawing area and your

cursor should change to this one:

Just move the new cursor over the cube until it is highlighted and click on it. Press <Enter> to end the command. It will look like absolutely nothing happened. You may have even done it a couple time to try and make it work. The only way to confirm that the material is attached to the cube is to 'render the scene'. This is easy - just type in Render and press enter. You'll see that a new window opened and rendered your cube.

Use these commands to apply materials to the solid objects you have drawn. Materials cannot be applied to wireframe objects or those drawn with line thickness

In many cases, rendering using object colours or the use of materials from the AutoCAD Material Library is all that's required to produce a semi-realistic render of a scene. However, sometimes you might want something specific. This tutorial shows you how to create and use a material that looks just the way you want it.

Consider the example above. In the image on the left, the ground has been rendered in the object colour and this looks perfectly fine. But say we wanted to give the impression of a close mown lawn as illustrated in the image on the right. Object colour alone can't do this and none of the materials in the Material Library look like this. The only option is to create our own material. This tutorial uses the example of mown grass but the basic principles hold true for any custom bitmap material.

Adding sunlight to your drawing

Introduction

Once you start working with solid models and rendering them, you will want to add lighting effects to your model. One of the most common requirements is to add sunlight to your drawing. AutoCAD has some very powerful and useful features for accurately creating sunlight effects.


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As you may have realized by now, you don't need lights in a scene in order to render a model. Figure number 1 on the left shows the effect of rendering without lights. As you can see, the results are rather uninspiring and there are no shadows. AutoCAD calculates the lighting in a scene where there are no lights by determining the the angle of incidence between the object faces and the line of sight. Faces that are perpendicular or near perpendicular to the line of sight are displayed brighter and faces further from the perpendicular are shown darker. The effect is similar to what you would see if the light source was placed at the camera position; perpendicular faces would reflect more light and faces further from the perpendicular would reflect less light. In figure 1, you can see that the vertical faces of the hedge, facing the viewer

are bright, whereas the ground plane is quite dark. Although this effect enables you to clearly see your model, it is far from realistic.

In order to add some sunlight to our scene, we will need to add a light that simulates the sun; AutoCAD calls this type of light a "Distant Light". This is much easier than it sounds and AutoCAD has some very user-friendly tools to help.

As you can see from figures 2, 3 and 4, not only can you simulate sunlight but you can control the time of day, the day of the year and the geographic location. Also, because the renderer can create accurate shadows based upon your parameters, you could even use these techniques to create a shadow analysis.

The three sunlight images on the left show the light and shadow effects on a garden at different times of the day on the 25th June in London. This is all possible without needing to know the first thing about solar geometry!

This tutorial will take you, step-by-step through the process of creating sunlight, modifying it and making the necessary shadow and render settings.

Overview & Fast Track

Adding sunlight and rendering a drawing is essentially a 5 step process. If you are familiar with AutoCAD, you may be able to create sunlight by following the Fast Track steps below.

1. Create a Distant Light using the Light command, View RenderLight… from the pull-down menu. Set the light type to "Distant Light" and click the New… button.

2. Name the light and set Shadow Type to "Raytraced" in the New Distant Light dialogue box. Give the new light a name. Click the checkbox to turn shadows on and then click the Shadow Options… button. Click the checkbox to turn "Ray Traced Shadows" on.

3. Set the Time using the Sun Angle Calculator. Click the Sun Angle


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AUTOCAD Calculator… button in the New Distant Light dialogue box.

4. Set the Location from the Sun Angle Calculator dialogue box. Click the Geographic Location… button in the Sun Angle Calculator dialogue box.

5. Render the Scene using the Render command, View RenderRender… from the pull-down menu. Set the "Rendering Type" to Photo Raytrace and click the checkbox to turn "Shadows" on.

You can use any 3D drawing to follow this tutorial providing that you have drawn a ground plane on which the shadows can be projected.

Getting Started

Open the Garden.dwg file. You may notice that it is a little slow to open. This is because the garden is constructed from solid objects and AutoCAD has to load some extra bits of the program to deal with them. The opening view is an aerial perspective. This was created using the DVIEW command but you could also use 3D Orbit. The view has been saved so that you can return to it at any time

using the Named Views command, from the Standard toolbar or View Named Views…. Highlight the view name, "Sun View", click the "Set Current" button and then click OK.

In addition to the saved view, the garden drawing also has the various render settings

already saved for you. However, if you are not familiar with rendering, it would be useful to have a quick go now so that you know what to expect later in the tutorial.

After opening the Garden.dwg, select View Render Render… from the pull-

down menu or click on the render toolbar to display the Render dialogue box. Since all of the settings are already made, simply click the OK button. After a few moments, the rendered image will appear in your viewport and your screen should look something like the image above. Notice that the render background has been set to white. This just makes the rendered objects easier to see. Notice also that some of the objects have materials assigned.

Note that rendered views are not interactive, they are just still images, like photographs. You cannot pan, zoom or pick objects in a rendered view as you can in shaded views. Therefore, you must return to your previous viewing mode before continuing with any drawing work. To do this, you must regenerate the view, select View Regen from the pull-down menu.

The rendered image that you see is shown with the default lighting as described above and illustrated in figure 1. We have not yet added any lights, so this is the next thing to do.

Adding a Light

Toolbar

Pull-down View Render Light…

Keyboard LIGHT

The first step toward simulating sunlight is to create a new "Distant Light".

AutoCAD can create 3 different types of light, namely, Point Light, Spotlight and Distant Light. It is important to understand how each of these light types affects the


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AUTOCAD final rendered image. A point light radiates light in all directions from a single point. A real-world example of this type of light is the bulb of a ceiling pendant light. A spotlight creates a conical light that is also directional. This is similar to a real-world spotlight. Distant lights differ from both point lights and spotlights in that their light rays are not radial, they are parallel.

Why are distant lights used to simulate sunlight? Well, although light rays from the Sun are radial, we are so far away from the Sun that the angle between light rays is very small by the time they reach the Earth. To all intents and purposes, they are parallel and since light rays from distant lights are parallel, they most closely resemble sunlight.

So, to create a new distant light, select View Render Light… from the pull-down menu. When the Lights dialogue box appears, select "Distant Light" from the drop-down list and then click the New… button. This will take you to the New Distant Light dialogue box.

Configuring a Distant Light

The second step to simulating sunlight is to name the light and to set the shadow options.

Click in the "Light Name" edit box and type the name of your new distant light. For the sake of simplicity, it might be sensible to call the light "SUN". However, you can call it anything you like providing that it is eight characters or less and doesn't include any of

the normal illegal characters such as spaces, asterisks, slashes and dots. If the light name you choose is not liked by AutoCAD, you will see a small error message in the lower left-hand corner of the dialogue box saying "Invalid name".

Setting shadow options for a light involves turning shadows on and then specifying the shadow type. When you create any light, you can decide whether it will cast shadows or not. In some cases it is desirable that lights do not cast shadows. This ability to control shadow casting means that you could build a scene with a number of lights, some of which cast shadows and some of which don't. To turn shadows on, click in the "Shadow On" checkbox (shadows are turned off by default).

Now you can set the shadow type. Click the Shadow Options… button to display the Shadow Options dialogue box.

Setting Shadow Options

The AutoCAD renderer can create three different types of shadows. The default shadow type is "Shadow Map" and the alternatives are "Volumetric" and "Ray Traced". You can see from the illustrations below that the shadow map and ray traced shadow types give quite different results. For most objects, the difference between Volumetric and Ray Traced shadows is very small. See All about Shadows for a full description of these shadow types. The type of shadow you use is entirely up to you but


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AUTOCAD in general, ray traced shadows tend to give a better result.

The Shadow Options dialogue box is used to specify which shadow type is used when you render the scene. The default shadow type is the shadow map.

Click the "Shadow Volumes/Ray Traced Shadows" check box to change the shadow type. Your dialogue box should now look like the one on the right. Click the OK button to return to the New Distant Light dialogue box.

Using the Sun Angle Calculator

The third step in simulating sunlight is to set the date and time using the Sun Angle Calculator. From the New Distant Light dialogue box, click the Sun Angle Calculator… button to display the Sun Angle Calculator dialogue box.

In order to set the date and time, you must specify the date, the time, the time zone and decide whether you want daylight savings or not.

Starting at the top of the left-hand column in the dialogue box, click in the "Date" edit box and type the date. Note that dates are in the American format (mm/dd). Next, click in the "Clock Time" edit box and enter the time. Note that this is in 24 hour format or military time. If you wish, you can use the adjacent slider bars to set the date and time but it is very difficult to control accurately and is therefore not recommended.

Using the drop-down list, select the required time zone. For example, if your site is in the UK, select the "GMT/WET" option. Finally, you need to decide whether you would like daylight savings to be calculated. This option will automatically convert GMT (Greenwich Mean Time) to BST (British Summer Time). Most likely you will want to have this option turned on, so click the "Daylight Savings" checkbox.

You will notice that AutoCAD allows you to specify the latitude and longitude of your site. These values must be known in order for AutoCAD to accurately calculate the angle of the Sun. In most cases you won't know these values but fortunately, AutoCAD can help us to locate our site Geographically. Click the Geographic Location… button.

Setting the Geographic Location

The fourth step in simulating sunlight is to specify the geographic location of your site. The Geographic Location dialogue box enables you to do this in a number of ways.


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The first thing to do is to specify which continent your site is in. Use the drop-down list, centre top of the dialogue box, to select a continent. Once you have done this, you have a number of options. You can simply select the name of a city from the list on the left. You can also select a city by checking the "Nearest Big City" option and picking a point on the map. If your site is not near a big city, you can deselect this option and simply pick any point on the map. Obviously it is very difficult to accurately pick a location from such a small map but you should be able to get close enough to generate realistic shadows.

You have now made all the settings that are needed to simulate sunlight. Click the OK button to return to the Sun Angle Calculator dialogue box. Click the OK button again to return to the New Distant Light dialogue box, click OK a third time to return to the Lights dialogue box and finally, click OK one more time to complete the specification for your distant light.

This might be a good time to save your drawing if you haven't already done so.

Rendering the Scene

Toolbar

Pull-down View Render Render…

Keyboard RENDER

The fifth and final step to simulating sunlight is to render a view of your drawing in order to show the effects of light and shadow.

Start the Render command by selecting View Render Render… from the pull-down menu. The Render dialogue box will appear. First, make sure that the Rendering Type option is set to "Photo Raytrace". Next, make sure that "Shadows" is checked in the Rendering Options section of the dialogue box. Shadows will not be generated if this option is not checked, even if shadows are turned on for your lights.

If you are not using the Garden sample drawing, you should also check that the Destination is set to "Viewport". You may also like to set the render background colour to white.

When you are sure that all settings have been made correctly (your dialogue box should look similar to the one illustrated above), click the Render button. AutoCAD will take a few seconds to render the scene (times will vary depending upon the complexity of the scene and the speed of your computer).

Modifying Sun Light

Once you have created your first sunlight render, you may want to change the time of day or date of the year in order to demonstrate the changing effect of sunlight on your site. You can modify your distant light settings at any time. To do so, select View Render Light… from the pull-down menu to go to the Lights dialogue box. Select your light from the list on the left of


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AUTOCAD the dialogue box and click the Modify… button. This will take you to the Modify Distant Light dialogue box.

From here you can modify any of the settings you made when you first configured the light. When your changes have been made, render the scene again and you will see the results of your modification. You could use this technique to create images of your site at hourly intervals during a single day or at the same time of day at different times of the year. This will give a good idea how sunlight will affect your site at different times,

ANIMATION & SLIDESHOW USING SLIDES AND SCRIPT

1. Open the files will be used in animation

2. Apply Zoom-extents for every drawing.

3. Use MSLIDE to create slides based on the open drawings. Name the slides S1, S2, and S3 respectively. Save the slides in a folder that belongs to AutoCAD file search path.

4. In command line enter Notepad and then press Enter twice. The Notepad window appears.

5. Enter the proper text to create the slide show [Figure 1].

Figure 1

Notes:

► The "delay 2000" causes a 2 second delay between subsequent slides.

► The "rscript" repeats the script from beginning.

6. Save the file as "slide_show.scr".

7. In AutoCAD, start a new drawing.

8. In command line enter SCR and then press Enter. The Select Script File dialog box appears [Figure 2].

Figure 2 - Click on image to enlarge

10. Locate and open "slide_show.scr". The slide show begins.

11. To exit the slide show press Esc.


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AUTOCAD 12. Invoke REGEN to remove the current

slide from screen.

HOW TO CREATE ANIMATION”WALKTHRU”

1. DRAW THE PATH

Create a PATH layer and make it current.

1.Draw the Camera Path

In the plan view, use Zoom out, to put plenty of space around the rooms, then use

polyline to draw the camera path through the spaces. Select move, pick the camera-path line, press , pick anywhere, then type @0,0,1700. This moves the line up to eye height (vary this height if you wish).

2.Draw the target path

Select move , pick the camera-path line, press , pick anywhere, then type @0,0,1500. This moves the line up to just below eye height (vary this height if you wish).

At Command line type ANIPATH

1.Select the camera path( Path name: Path1)

2. Select the target path (Path name Path 1)

3.Set number of Frames

4.Choose visual style (Wireframe, hidden or Realistic)

5. Choose file Format (MPG, AVI, or WMV)

6. Click Preview (sit back and relax while AutoCAD does its stuff...)

7. Save the File

8. Click on the Start button on the task bar, then move the cursor to All programs then move the cursor to” Windows Media Player", select File - Open set the drive and directory, select the animation file and select Open.


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RENDERING (For AutoCAD 2004) SETUP CAMERA (Target Camera)

1. Set the Shade mode to 2d wireframe. Command: SHA (enter) 2D )enter)

2. Set the view to plan view or Topview

at the Menubar click VIEW/ 3dviews/ Topview

3. command: DVIEW (enter) select Blocks: select blocks or objects (enter) specify Target location: .xy (enter) of click TP need Z 1.3 (enter) specify camera location: .xy (enter) of click CP need z 1.4 (enter) Enter option [CAmera/TArget/Distance/POints/PAn/Zoom/TWist/CLip/Hide/Off/Undo]:D (enter) Adjust the distance( using the mouse) left click at drawing area (enter)

SAVE VIEW Command: DDVIEW (enter) Click NEW Enter Name Ex: View 1 Click OK OK LOAD VIEW Command: DDVIEW (enter) Select view name Click Set current Click OK

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MATERIALS 1.Command: RMAT (Enter) 2.Click MATERIALS LIBRARY

3. Choose a Material from the list 4. Click PREVIEW 5. Click IMPORT 6. CLICK OK

7. Click ATTACH

8. Select an object were you want to apply the material (enter)

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Then click OK

9. command: rr (enter) 10. Click RENDER

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TO MODIFY SCALE AND ROTATION OF BITMAP 1. Right click DRAW or MODIFY Toolbar 2.check RENDER 3.On Render toolbar Click MAPPING Icon

4. Select an object for mapping (Enter)

5. Click Adjust Coordinate

6. Rotation: type the angle of bitmap 7.Click ADJUST BITMAP

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8.You may change the scale of Material The default is U=1 V=1 Higher value will make the material appearance smaller. 9.Click ok 10. ok 11.. ok

12. command: RR (enter) 13. Click RENDER

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to make a Material transparent or translucent 1.command: RMAT (enter) 2.select a material then Click MODIFY

3. Select TRANSPARENCY 4. Change value range 60-95 5. Click OK OK

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Adding Background 1command: RR (enter) 2.Click BACKGROUND

3. click IMAGE 4. Click FIND FILE

5. Select the drive and folder where the file was saved 6.Select a file 7.Click OPEN

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8. Click RENDER

POINTLIGHT 1. command: LIGHT (enter) 2. Select POINT LIGHT 3. Click NEW

4.Enter Light name ex: light1 5.Change Intensity= 2 6.Check Shadow ON 7. Click MODIFY

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8.Click light location

9. Click OK

10. command: rr(enter) 11. At Rendering type: Select PHOTO REAL 12.Check all Rendering Options Smooth shades,Apply Materials, Shadows and Render cache 13.Click MORE OPTIONS

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14. Under Anti Aliasing choose HIGH 15.Under FACE CONTROLS Check Discard back faces And Back face normal is Negative 16. Under TEXTURE MAP SAMPLING Choose Mipmap sample 17. Click OK 18. Click Render

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AUTOCAD DISTANT LIGHT

1. command: Light (enter) 2. select Distant light 3. click NEW

4. Enter name ex: SUN 5. check Shadow on 6. click shadow option

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7. Check Shadow Volume/Ray Traced Shadow 8. click OK 9. click OK 10. click OK 11. command: RR (enter) 12. Under Rendering Option make sure that shadows are checked. 13. click RENDER

14. At Render Toolbar click Landscape 15. Select 1 from the list ex: sweet gum summer 16. click Preview 17. click Position

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18. click were you want to position the tree 19. click OK 20.Adjust the scale of the tree then Render the scene

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RENDERING (For AutoCAD 2006 to 2008) SETUP CAMERA (Target Camera)

4. Set the Visual style to 2d wireframe. Command: SHA (enter) 2D )enter)

5. Set the view to plan view or Topview

at the Menubar click VIEW/ 3dviews/ Topview

6. command: CAMERA (enter) specify camera location: .xy (enter) of click CP need z 1.4 (enter) specify Target location: .xy (enter) of click TP need Z 1.3 (enter) (?/name/location/height/target/lens/clipping/view/exit)<exit> V (enter) Switch to camera view? {yes or no} Y (enter)

SAVE VIEW Command: DDVIEW (enter) Click NEW Enter Name Ex: View 1 Click OK OK

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LOAD VIEW Command: DDVIEW (enter) Select view name Set current Click OK Assign Materials 1.Command: RMAT (enter) 2.Click CREATE NEW MATERIALS ICON

3.Enter materials Name Example: Sofa then click ok

4.Under Diffuse map click SELECT to browse for an image to use as a texture map 5.Choose a file then click OPEN

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6. Choose a Template For Metals- use Realistic Metal Advance Metal Metal-Brushed Metal-Polished Metal-Flat Metal For Tiles- use Ceramic Tile,Glazed For Fabric- use Fabric For Glass- use Glass Clear or Translucent For Mirror- use Mirror For Walls- use Paint Flat Paint Gloss Paint Semi Gloss Etc…..

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7. To modify the scale and rotation of the bitmap click the icon shown below

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Bitmap Scale U=2 V=2 Rotation= 0

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ASSIGN LIGHT Point light

1. command: Light (enter) Enter Light type [Point/ Spot/ Distant] <Point> P (enter) Specify light Location <0,0,0,> click light location

Command: light (enter)(enter) Enter light type [Point/Spot/Distant] <Point>: P (enter) Specify source location <0,0,0>: click light location Enter an option to change [Name/Intensity/Status/shadoW/Attenuation/Color/eXit] <eXit>: N (enter) Enter light name <Pointlight7>: light1 (enter) Enter an option to change [Name/Intensity/Status/shadoW/Attenuation/Color/eXit] <eXit>: I (enter) Enter intensity (0.00 - max float) <1>: 1 (enter) Enter an option to change [Name/Intensity/Status/shadoW/Attenuation/Color/eXit]

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<eXit>: S (enter) Enter status [oN/oFf] <On>: on (enter) Enter an option to change [Name/Intensity/Status/shadoW/Attenuation/Color/eXit] <eXit>: w (enter) Enter shadow settings [Off/Sharp/soFt] <Sharp>: S (enter) Enter an option to change [Name/Intensity/Status/shadoW/Attenuation/Color/eXit] <eXit>: X (enter)

2. Render the scene(before rendering, create new material,change color to white and set the self illumination to 100 then apply the material to the light) Shadow on Shadow off

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DISTANT LIGHT

1. Command: light (enter) Enter light type [Point/Spot/Web/Targetpoint/Freespot/freeweB/Distant] <Distant>: d (enter)

Specify light direction FROM <0,0,0> or [Vector]: click DF Specify light direction TO <1,1,1>:click DT Enter an option to change [Name/Intensity/Status/shadoW/Color/eXit] <eXit>: I (enter) Enter intensity (0.00 - max float) <1.0000>: 1 (enter) Enter an option to change [Name/Intensity/Status/shadoW/Color/eXit] <eXit>: s (enter) Enter status [oN/oFf] <On>: on (enter) Enter an option to change [Name/Intensity/Status/shadoW/Color/eXit] <eXit>: x (enter) 2. Render the Scene

Command: RR (enter)

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Add Background using Photoshop

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Date post:	24-Dec-2015
Category:	Documents
Upload:	profmlocampo
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