Section 21.1 Project Documentation Section 21.2 Document Management Media Management Chapter Objectives Describe how the engineering design team uses and manages graphic communiation. Learn to use draw- ing storage and retrieval systems for both hard-copy and electronic media. Describe several ways of producing interme- diates during the draw- ing revision process. Outline methods of reproducing board- and CAD drawings. • • • • 21 Where Are Those Other Drawings? Larry Wood says of his early work that after choosing one car from the ten or 20 drawings on the wall, he would basically throw away all but the one chosen. Is this standard practice today? 708 AP Photo/Nam Y. Huh
Transcript
Section 21.1 Project Documentation
Section 21.2 Document Management
Media Management
Chapter ObjectivesDescribe how the engineering design team uses and manages graphic communiation.Learn to use draw-ing storage and retrieval systems for both hard-copy and electronic media.Describe several ways of producing interme-diates during the draw-ing revision process.Outline methods of reproducing board- and CAD drawings.
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21
Where Are Those Other Drawings? Larry Wood says of his early work that after choosing one car from the ten or 20 drawings on the wall, he would basically throw away all but the one chosen. Is this standard practice today?
708AP Photo/Nam Y. Huh
Go to glencoe.com for this book’s OLC to learn more about Larry Wood.
Larry Wood, Mattel′s Hot Wheels® chief designer, got ‶hooked″ on cars when his dad gave him a car magazine that opened his eyes. ‶I didn′t know people [designed the cars]. I just assumed a car came from a factory, you bought it at a car lot and that was it.″
Wood thinks that some of his designs may have
infl uenced Detroit. ‶Somebody said of the new Mustang… that all the designers at Ford actually had one of our cars called the Pony-Up on their desks.…They probably thought if Hot Wheels can do this, …we can design it this way.″
Drafting CareerLarry Wood, Automotive Design
Academic Skills and AbilitiesMath, especially precalculus or calculusScienceLanguage artsSocial studiesComputer technologyDrafting skillsProblem-solving abilities
Career PathwaysA bachelor′s or master′s degree is required for
most entry-level positions. New hires usually receive one to three years of on-the-job training before advancing to higher-level corporate positions such as chief designer, design department head, or other supervisory positions.
Preview Engineering design teams produce a number of documents while working on a project. What types of documents do you think they make, and how do you think they identify them?
Content Vocabulary• media • Gantt chart • PERT chart
Academic VocabularyLearning these words while you read this section will also help you in your other subjects and tests. • complexity • output
Graphic Organizer
Use a chart like the one below to organize your notes about the use of computer servers in han-dling information, including storage.
Go to glencoe.com for this book’s OLC for a downloadable version of this graphic organizer.
Academic Standards
English Language Arts
Read texts to acquire new information (NCTE)
Use diff erent writing process elements to communicate eff ectively (NCTE)
Mathematics
Number and Operations Compute fl uently and make reasonable estimates (NCTM)
NCTE National Council of Teachers of English Language Arts
Types of DocumentsWhat kinds of reports and graphic communication are used to document a project?
Graphic communication is used through-out the design and production of structures and products.
Although working drawings serve as the basic form of graphic communication for design and manufacture, many other types of documents are used throughout business and industry. Various types of written docu-ments, such as contracts and invoices, are important forms of communication required for legal and operational purposes. These documents, in addition to drawings, may be produced by hand or by computer, and they can be stored on paper or fi lm, or as an electronic fi le. Collectively, these are called media (plural; singular medium). The media on which important documents are stored need to be managed effi ciently so that the business can run smoothly.
Many companies use networked computer systems to help control the fl ow of media and other work processes. The system adminis-trator, who may also be a project manager or department head, controls the fl ow of infor-mation to each computer that is connected to the network. Networked systems allow CAD operators to share important fi les such as symbol libraries and template drawings. The shared fi les are usually stored on a powerful central computer with extensive storage capa-bility called a server.
This chapter describes some of the many types of documents that the engineering design team typically uses. Large companies organize engineering design teams to control the design and manufacture of major projects and products. The types of documents that these teams produce depend partly on the products’s size and complexity. Note: For the purpose of this chapter, the terms project and product are used interchangeably.
ReportsThe engineering design team develops
many technical reports, such as bills of mate-rials and stress analyses. These reports, which
may include both text and graphics, are often generated directly from the CAD software that was used to create the plans. The results are documented in a formal report using word processing software.
Five basic types of technical reports are gen-erally needed during the design and manufac-ture of a new product (see Figure 21-1).
The design report states the client’s needs and provides the designers’ early analysis of the project.The technical report is a detailed analysis prepared by the designers that details all resources necessary for researching, design-ing, and developing the project.The market report describes the marketabil-ity of the proposed or revised product, the target consumer base, product price, and potential profi t. This report impacts the fi nal decision on whether the company manufactures the product.The contract report includes all details of manufacture or construction. It may also include specialized tooling requirements if new tools must be designed and manufac-tured to produce the product.Progress reports are reports made periodi-cally on the project’s current status. These reports allow managers to check the status of the project and to review compliance with the specifi cations in the contract.
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Figure 21-1
The engineering design team creates several diff erent types of reports during the course of a project.
Section 21.1 Project Documentation 711
Project Organization ChartsOne major function of the engineering
design team is to meet the needs of current and potential clients. The team’s work must be organized so that problems can be solved as quickly and inexpensively as possible. Therefore, in most companies, the production schedule plays an important part in the orga-nization’s operation. This is true whether the product is a skyscraper, an automobile, a lux-ury cruise liner, a computer, or a child’s toy.
The head of a design project or planning department may use several different types of charts to help manage and control the project. Two of the most commonly used charts are Gantt and PERT (project evaluation and review technique) charts. A Gantt chart (see Figure 21-2) separates an operation or project into discrete elements and assigns a certain amount of time for each step. The time allot-ted varies depending on the complexity of the operation. A PERT chart assigns probabilities
Rounding DecimalsWhen preparing the various reports needed for a project, you sometimes need to round numbers to fewer digits. For example, a market analysis might include numbers of specifi c responses from a customer survey. When these numbers are converted to percentages for the market report, the percentages are rarely whole numbers. They are usually decimal fractions that must be rounded for ease of reading. For example, 25.63220% rounded to two places would be 25.63%.
Round the following decimal fractions to two places:
34.62458%15.18246%
13.11558%
The procedure for rounding is as follows: 1. When the left-most digit dropped is
less than 5, the last digit kept does not
change. For example, 15.232 rounded to two decimal places would be 15.23.
2. When the left-most digit dropped is more than 5, the last digit kept should be increased by 1. For example, 6.436 rounded to two decimal places would be 6.44.
3. When the left-most digit dropped is 5 followed by at least one digit more than zero, the last number kept should be increased by 1. For example, 8.4253 rounded to two decimal places would be 8.43.
4. When the fi rst number dropped is 5 followed by zeros, the last number kept is increased by 1 if it is an odd number. If it is an even number, no change is made. For example, 3.23500 rounded to two places would be 3.24. However, 3.22500 rounded to two places would be 3.22.
For help with this math activity, go to the Math Appendix at the back of this book.
Academic Standards
Mathematics
Number and Operations Compute fl uently and make
reasonable estimates (NCTM)
712 Chapter 21 Media Management
ACTIVITY APRIL MAY JUNE JULY AUGUST SEPT.
Analyze project requirements
Generate preliminary designs
Select final design
Finalize materials/processes
Create working drawings
Submit drawings for approval
Send approved drawings to mfg.
Figure 21-2
A Gantt chart shows how much time a company plans to spend on each phase of a project. It also helps companies work more effi ciently, by allowing managers to plan which processes can be done concurrently.
to production issues such as effi ciency and productivity. It then plots them against pro-duction activities and operations. This type of chart allows the project manager to accurately estimate production and output time.
Explain How does a Gantt chart help organize a project?
Records of Drawing
DevelopmentAs members of the engineering design
team develop a project, they keep a record of the design progress. In most companies, each project is assigned a unique contract number or job number for this purpose. This number must be included on all reports and drawings. The number is part of the information given in the title block of a drawing.
Section 21.1 AssessmentAfter You Read
Self-Check 1. Describe several ways that an engi-
neering design team uses and manages graphic communication.
Academic IntegrationEnglish Language Arts
2. Study the Gantt chart shown in Figure 21-2. Isolating one part of the process shown, use a different kind of chart or visual aid to communicate in a presenta-tion to your class how that portion of the process progresses from start to fi nish.
Drafting Practice 3. Devise a drawing management system
for the drawings you have created so far in class. Organize your drawings using a fi le system, a three-ring binder or port-folio, or use another system that allows you protect as well as easily manage and access them. Explain your management system in a brief presentation to the class.
Go to glencoe.com for this book’s OLC for help with this drafting practice.
Connect The documents the engineering design team produces, including electronic documents, must be stored carefully for their protection and easy location, as well as for revision when necessary. What measures would you take when storing them?
Content Vocabulary• closed
fi ling system
• open fi ling system
• microfi lm
• intermediate• photodrafting• diazo
• electrostatic reproduction
• hard copy
Academic VocabularyLearning these words while you read this section will also help you in your other subjects and tests.• considerable
Graphic OrganizerUse a chart like the one below to organize your notes about managing drawings.
Go to glencoe.com for this book’s OLC for a downloadable version of this graphic organizer.
Academic Standards
English Language Arts
Read texts to acquire new information (NCTE)
Use diff erent writing process elements to communicate eff ectively (NCTE)
Mathematics
Problem Solving Solve problems that arise in mathematics and in other contexts (NCTM)
Science
Science and Technology Understandings about science and technology (NSES)
Drawing
Management
Board Drawings
NCTE National Council of Teachers of English Language Arts
Managing Board Drawings What are the primary concerns when storing fi nished project drawings?
The drawings created in a drafting room each day must be carefully controlled to avoid misplacement or damage. In addition, after an original set of drawings has been com-pleted, it must be stored for future use. In some cases, the originals are modifi ed over a period of time as a product or structure is refi ned or updated. To meet these needs, most companies develop a comprehensive system for cataloging and storing original drawings. For example, many large companies keep the original drawings for a contract together under its contract number or job number. This makes the drawings easily available for copying or revising.
For the purpose of this discussion, the term paper documents includes drawings cre-ated using board drafting techniques regard-less of the medium on which the drawings were produced. For example, the term includes drawings created on polyester fi lm and on paper.
File SystemsMost companies use either a closed or open
fi ling system. In a closed fi ling system, one person is responsible for keeping the drawings and other documents safe. Although this per-son may have a staff that fi les and copies the documents, the number of people allowed to handle original drawings is tightly controlled.
Other companies favor an open fi lingsystem in which the original drawings are always available to anyone in the department. The open fi le system is generally not preferred because easy access to the original drawings can lead to mishandling.
Microfi lm StorageStoring board drawings in their original form
consumes considerable space. The draw-ings are often diffi cult to manage because of their size and because the overhead expenses, such as rent and temperature control, are often enormous. Therefore, many companies store board-produced drawings on microfi lm.
Microfi lm is a fi lm storage medium on which a large drawing is reduced to a very small size and recorded. This storage greatly reduces the amount of space necessary to store drawings. See Figure 21-3.
A number of photographic formats have been used in microfi lming. However, 16 mm and 35 mm are the most popular fi lm sizes. The fi lm has high contrast and high resolu-tion, and is fi ne grained to produce high-quality drawings with good detail. When a drawing stored on microfi lm needs to be cop-ied or revised, a copy is made directly from the microfi lm. The microfi lm copy can be scaled to fi t any standard size paper.
Another option that is now available for storing large-format drawings is an online repository. Companies use a scanner to make a high-quality scan of valuable originals and use a secure online storage and retrieval service to manage them. Drawings can be viewed, retrieved, or sent to a local printer on demand.
Converting Board DrawingsCompanies use other methods to convert
board drawings to an electronic format for storage and other purposes.
Digitizing the DrawingWhen you digitize a drawing using a
digitizing tablet, you end up with a fi le in a CAD-readable format. This method has both advantages and disadvantages. The primary
Figure 21-3
Because microfi lm stores large drawings in a very small format, a single micro-fi lm data card can hold many drawings.
Section 21.2 Document Management 715
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advantage is that if the digitization is done correctly, the resulting electronic fi le is very accurate. Like all CAD drawings, digitized fi les are in vector fi le format. In other words, the placement of the geometry is defi ned using a set of mathematical instructions. A line, for example, exists in a CAD fi le as a location for the starting point of the line and a vector, or mathematical value that tells the distance the line travels and in what direction. This mathe-matical calculation ensures that the electronic drawing is both clear and accurate.
This process requires access to a CAD sys-tem with a digitizing tablet, and digitizing a drawing accurately takes time, effort, and skill. Not every CAD operator is skilled in the process of digitization, and not every CAD sys-tem includes a digitizing tablet. Finally, digiti-zation does not produce a fi le that is directly usable by the desktop publisher. It must be further processed within CAD or other illus-tration program before it can be used.
Scanning the DrawingAnother method of creating an electronic
fi le from a board-generated drawing is to scan it using a high-quality scanner. This method is faster, because it can create electronic fi les in a format that can be used directly by other soft-ware programs. Most scanners are capable of scanning fi les in several formats. You should fi nd out the acceptable formats for your com-pany fi rst. It is generally safe to scan to a TIFF or JPG format.
Scanning produces a raster fi le format. Unlike vector fi les, raster fi les to do not defi ne geometry using mathematical calculations. Instead, they consist of a collection of tiny dots called pixels (picture elements). Raster fi les are not as accurate as vector fi les. To cre-ate an acceptable raster fi le of a drawing that contains thin lines, you must scan the draw-ing at a very high resolution. This creates an accurate electronic fi le, but one that takes up a lot of storage space.
Scanning is the method of choice for small drawings because it is faster and easier than digitizing. For large, complex drawings, you should choose the conversion method care-fully. A scan of suffi cient clarity might be too large to store effi ciently. Some scanned fi les can exceed 150 MB in size.
Drawing Revision When a drawing is revised, the company usu-
ally must keep a copy of the original as well as of the revision. Instead of recreating the entire drawing for the revision, drafters generally use an intermediate. An intermediate, also called a secondary original, is a copy of a drawing that is used in place of the original. See Figure 21-4 for the process of using an intermediate to cre-ate a new original. The designer and drafter can change the intermediate without changing the original or tracing and redrawing.
The eight methods that follow are only some of the time-saving techniques drafters use to revise intermediates.
Scissors drafting The unwanted portions of an intermediate are removed with scissors, a knife, or a razor blade. Then a new inter-mediate is made to incorporate the change.Correction fl uids Drafters remove unwanted data from an intermediate by applying cor-rection fl uid.Erasable intermediates Erasable inter-mediates can be erased with ease. Non-erasable prints are then made from the intermediates. Block-out or masking The area to be blocked out is covered with opaque tape. Next, a print is made in which the masked areas produce blank spots. Changes are then entered into these areas to produce the revised original.Transparent tape Data can be added to a drawing by placing the data on paper or fi lm and then taping the data in place on an intermediate. Alternatively, data can be typewritten on transparent press-on material, which is then attached to the intermediate.Composite grouped intermediates When several drawings are to be combined, a composite grouping can be cut from inter-mediates and taped in place. A new inter-mediate is then made of the composite.Composite overlays Translucent origi-nal drawings can be combined into a composite intermediate by placing the originals in the desired places. The compos-ite is then photographed.Photodrafting Architectural and engineering teams often use photo drawings because
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Then tape the elements in their newpositions on a new form.
Photograph it on film with a mattefinish (the tape and film edgeswill disappear). Draw in whateverextra detail you want -- and you have a new original drawing.
First you make a clear film reproductionof the original and cut out the elements.
Say you have an existing drawing:
And you want to revise it like this.
they are generally easier to understand. In this intermediate drafting process, called photodrafting, photographs are overlaid with line work to create enhanced, anno-tated pictures of the product.
Drawing Reproduction Once a drawing has been completed, cop-
ies will be needed for the design engineer-ing team, factories and subcontractors, and the purchasing department. In choosing a method of drawing reproduction, the drafter must consider the following factors:
Purpose Why are the copies needed?Type of originals What is the size, weight, color, and opacity of the original medium used?Output quality How readable must the copies be? Should they be transparent or opaquei?Size of reproduction Are the copies to be enlarged, reduced, or the same size as the original?Speed of reproduction How many copies are
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Figure 21-4
Using an intermediate to rearrange the placement of drawings on a drawing sheet
needed? How quickly are they needed?Color of reproduction Should the copy be blue-line, blueprint, sepia brown, some other color, or a combination of colors?Cost of reproduction What are the esti-mated costs of materials, operations, and overhead?
Identify What is the purpose of an intermediate?
BlueprintsIn general, drafters, engineers, and trades-
people tend to refer to all types of media repro-ductions as blueprints or simply prints. Thus, the term blueprint has become a rather generic name for all types of media reproduction. In addition to the original blueprint (white lines on a blue background), the term is now used to include prints made by the diazo, electrostatic, and photographic reproduction processes.
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Section 21.2 Document Management 717
DEVELOPING SYSTEM: RECIRCULATING AMMONIA
DEVELOPING SYSTEM: SEMI-MOIST
A
B
DEVELOPERROLLS
AIR STREAMSEPARATES ORIGINALFROM PRINT
COMPLETED PRINT
LIGHTSOURCE(UV LAMP)
ORIGINALRETURNS TOOPERATOR
ORIGINAL ANDSENSITIZED PAPER
REAR DELIVERYSEALING SLEEVE
FRONT DELIVERY
PERFORATED ROLLERSDEVELOPER TANK
ORIGINAL RETURNSTO OPERATORAUTOMATICALLY CONTACT BELTS
AIR JET SEPARATOR
CONTACT CYLINDER
LIGHT SOURCE
ORIGINAL ANDSENSITIZEDMATERIAL
DiazoThe diazo method results in prints that
have dark lines on a white background. For this reason, the diazo process is sometimes called whiteprint. Diazo prints are made from drawings created on a translucent medium and exposed to diazo paper that has a light-sensitive coating. The light-sensitive diazo coating is developed, or treated chemically, to bring out the image. See Figure 21-5. The three methods used to develop the coating include dry process, semi-moist process, and pressure process.
Electrostatic ReproductionElectrostatic reproduction, also known
as photocopying, uses electrostatic force (static electricity) to reproduce original drawings. Elec-trostatic machines have a positively charged
plate. To make a copy, the original drawing is placed between the plate and a light source. Where light strikes the charged surface, the charge dissipates, or goes away. Where the origi-nal drawing obscures the light source, the charge remains on the plate. A negatively charged pow-der called toner adheres to the charged surfaces of the plate because it is attracted to the oppo-site (positive) charge on the plate. The machine then produces an electrical discharge in which the toner particles “jump” to the copy paper. The paper is then exposed to an intense heat source to fuse the toner to the paper.
Photographic ReproductionFilm companies also provide ways to repro-
duce engineering drawings. Copy cameras make images of the drawings on light-sensitive material, such as fi lm coated with silver halide. High-contrast fi lms are used to give lines uni-form widths and blackness. The images are developed and fi xed using procedures similar to those used to develop ordinary camera fi lm.
Film makes better prints than the diazo pro-cess. The fi lm has a matte fi nish, and changes can be made with ink or pencil. Photographic reproduction also allows drafters to reduce or enlarge images easily. However, photo repro-ductions are considerably more expensive to produce, and their use is limited to very spe-cifi c applications.
Explain How is toner used in the electrostatic reproduction process?
Managing CAD DrawingsWhat can you do to ensure your CAD fi les are not lost or damaged?
Concerns relative to electronic fi le manage-ment are quite different from those related to media management. Whereas space is a con-cern for paper documents, permanence is more of an issue for electronic documents. For stor-age purposes, for example, the chosen medium must remain reliable over a period of years. In addition, the medium must be readable by computers produced in the future as well as those used at the time the drawings are created.
Figure 21-5
Diazo dry process (A) and semi-moist process (B)
718 Chapter 21 Media Management
Standard Backup StrategiesElectronic documents such as CAD draw-
ings require protection even while they are being created. A momentary power outage, or even a power fl uctuation, can destroy any por-tion of a drawing that has not yet been saved to a storage medium such as the computer’s hard drive. Although saving a drawing is ulti-mately the individual drafter’s responsibility, companies usually have standard policies and procedures to help protect the fi les. For exam-ple, a complete backup strategy for a CAD department might be this:
CAD operators are required to save their drawings at least once per hour to the CAD system’s hard drive.At the end of each day, the CAD operator must copy all of the day’s work onto the company server.At the end of every week, the department head must make a master copy of all proj-ect fi les on the server. This master copy will be stored on a recordable CD or DVD and will be stored off-site in a fi reproof location.
Some large companies that have networked CAD systems prefer to back up the project fi les at night. This can be done by a separate operator or group, or it can be programmed to occur automatically.
Uninterruptible Power SupplyMany companies also install an uninter-
ruptible power supply (UPS) to protect their computer systems from outages and surges. The UPS plugs into the power line between the power outlet and the computer. It pro-tects the computer by detecting power failures and switching on a backup battery within microseconds. UPS units are capable of sus-taining computer systems long enough for drafters to save their work and shut down the computers.
Storage StrategiesStorage of electronic documents requires
both short-term and long-term strategies. For short-term storage, many companies now use a complex RAID (redundant array of independent disks) storage system. For long-term storage, most companies use redundant
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hard drives or DVDs. In either case, the stor-age medium is located off-site for maximum security.
Although electronic fi les require much less space than paper documents, long-term storage space may still be an issue, especially for large companies. As CAD software becomes more complex, drawings may become larger, requir-ing more space on the storage media. Also, many companies today send fi les to clients and associates by e-mail or by fi le transfer pro-tocol (FTP). For these reasons, keeping drawing fi les as small as possible is considered not only good practice but also a practical necessity.
List What are the major concerns regarding electronic documents?
Most CAD software has the ability to purge a drawing fi le. The purging process removes any unused layers, text styles, dimension styles, blocks, and other unused objects in a drawing. These items can be purged from the document in a single operation or individually, giving the drafter complete control over drawing content. For example, AutoCAD drafters use the PURGE command to select the types of objects to be purged from the drawing.
If the client does not have a high-speed Inter-net connection, large working drawings with multiple external references or raster images (photographs) should usually be sent using one of the following portable storage media:
Removable fl ash drives Removable USB fl ash drives can store from 32 MB to 7 or 8 giga-bytes (GB) of data. Recordable CD or DVD To distribute larger volumes of data, a recordable CD or DVD is an excellent choice. Most CDs can hold 600 to 700 MB of data. DVDs can store more than a gigabyte. This media is inex-pensive and provides very reliable storage since magnetic fi elds will not harm data stored on them.
Revision of CAD Drawings When a company uses CAD to create draw-
ings, it does not need intermediates. Because the data is in digital form, the CAD operator
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Section 21.2 Document Management 719
merely retrieves a digital copy of the original design. As a matter of good practice, the fi rst thing the CAD operator should do is make a copy of the fi le with another name, to protect the original drawing. The name change usually consists of adding a revision letter or date to the name, so that members of the design team will know which drawing is the latest version.
After specifying the revision number, the CAD operator makes any required changes on the drawing. Once the changes have been made, the operator saves the new version of the drawing, updates the revision block, and reprints or plots a new original showing the updated information. The original design remains unchanged.
Reproduction of CAD DrawingsCAD drawings are naturally easier to repro-
duce than board-drafted drawings, because a new copy can be printed at any time from the drawing fi le. When CAD drawings are reproduced by creating a print from the origi-nal drawing fi le, each “copy” is actually an original.
The machines used to create a hard copy(paper copy) from an electronic drawing fi le are necessarily different from those described
in the previous section. CAD materials must be printed using a printer or plotter that can communicate directly with the CAD system. The printers and plotters commonly used to create hard copies of CAD drawings include electrostatic plotters, pen plotters, ink-jet printers, and laser printers (see Figure 21-6).
When a large number of copies of a CAD drawing are needed, some companies use black-and-white or color photocopiers. How-ever, color photocopiers are costly and require expensive supplies. Therefore, many com-panies send their original drawing fi les to a reproduction service company for reproduc-tion. The service company reproduces the CAD drawings using the method and medium requested.
Converting CAD drawingsIllustration programs allow you to adapt
a drawing to use in a company document, such as a presentation or a product manual. To use them with other programs, CAD draw-ings must sometimes be converted into otherformats. AutoCAD creates drawings in DWG or DXF formats or as IGES fi les. These fi le for-mats work well for sharing drawings among different CAD systems.
Figure 21-6
Ink-jet technology provides brilliant color for drawings, charts, and other project documents at a relatively low cost.
720 Chapter 21 Media Management
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Most CAD programs can also export draw-ing fi les to other fi le formats, such as EPS, which is acceptable for many illustration and desktop publishing programs. When you export a drawing into another format, such as EPS formats, the exported fi le does not affect the original fi le at all. So if you make changes to the original fi le, you must re-export the fi le.
There are several kinds of EPS format, and the one created by AutoCAD may not be accepted by a particular software, even though the soft-ware accepts EPS fi les. Also, exporting a draw-ing fi le to EPS format may not preserve the line widths in the original drawing. Other problems
Section 21.2 AssessmentAfter You Read
Self-Check 1. Explain how drawing storage and
retrieval systems are used for both hard copy and electronic documents.
2. Describe how intermediates are used in the drawing revision process.
3. List the methods for reproducing board and CAD drawings.
Academic IntegrationMathematics
4. Lonnie’s family has a digital camera with 1560 pictures stored. Lonnie’s mother went through them and deleted one-third of the pictures. Then, his father went through and deleted another 45. Write and solve an equa-tion to fi nd how many pictures were left on the computer.
Solving Equations
Equations often contain grouping symbols such as parentheses or brackets. The fi rst step in solving these equations is to do the math within the brackets fi rst. Start with multiplication or divi-sion, then perform any addition or sub-traction from left to right.
Drafting Practice 5. In Chapter 7, Drafting Problem 6, you
created a multiview drawing of a cradle slide from a given pictorial. Retrieve your original multiview drawing. Use appropriate board or CAD techniques to change the radius of the cradle to 1.25″, as indicated in Figure 21-7. Do not change the original drawing. Be sure to include a revision block on the new version. After saving and clos-ing the drawing, determine the size and make of the drawing fi le. Reopen the drawing and purge any unused lay-ers and styles. Save the drawing again, close it, and recheck the size of the fi le. Calculate the difference in fi le size.
Go to glencoe.com for this book’s OLC for help with this drafting practice.
Figure 21-7
1.25
may occur. For example, EPS recognizes dashed lines, but the lengths of the dashes may be dif-ferent in the exported fi le. Since EPS recognizes only two dimensions, 3D CAD drawings, when exported, become two dimensional, and any hidden lines that you have removed in the CAD drawing reappear in the EPS version.
You can overcome some of these problems by importing the fi le created by AutoCAD into an illustration program such as Adobe Illustra-tor or Macromedia FreeHand. These programs allow you to touch up the fi les and save them into an EPS format that is recognized by desk-top publishing systems.
Section 21.1 In order to help manage the design and production processes, the engineering design team uses various reports and charts that contain important project information.
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Section 21.2 Drawings and other documents must be carefully numbered, cataloged, and stored so that they are protected and can be retrieved when needed.Intermediates are used in the revision of drawings, and can be created by cutting and pasting, erasing, masking with tape or correction fl uid, using an overlay, orphotodrafting.Originals can be reproduced by diazo, electrostatic, and photographic methods.
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Content Vocabularymedia (p. 711)Gantt chart (p. 712)PERT chart (p. 712)closed fi ling system (p. 715)open fi ling system (p. 715)microfi lm (p. 715)
Review Content Vocabulary and Academic Vocabulary 1. Use each of these content and academic vocabulary terms in a sentence or drawing.
Review Key Concepts2. Name and describe some of the reports a design team uses in managing a project.3. Describe how drawing storage and retrieval systems are used for board drawings and CAD
drawings.4. Summarize an intermediate’s role in the drawing revision process.5. Explain how methods of reproduction differ for board and CAD drawings.
722 Chapter 21 Media Management
Multiple Choice QuestionDirections Choose the letter of the best answer. Write the letter for the answer on a separate piece of paper. 9. Which of the following is not a factor
in choosing a reproduction method for drawings?
a. cost c. purposeb. attitude d. quality
Technology 6. Improving Effi ciency with
TechnologyThe second section of this chapter discusses
using technological systems to improve effi -ciency. In an essay or chart, point out the pos-itive and negative effects these technological systems could have on a drafting business. For each negative effect, suggest several solutions that could be implemented.
7. Information LiteracyThink about a management system as a
process of planning, organizing, and con-trolling work. Using information from the chapter and from at least two other sources, describe in a one-page essay how such systems can be as necessary as the performance of the actual work (i.e., design and production).
Mathematics 8. Understanding Data
Thomas is analyzing data about the con-sumer base of a specifi c company. He has information on age, gender, race, income, geographic location, and favorite product or products. Before he can compute any statis-tics, he has to decide whether the different variables he is analyzing are categorical data or measurement data.
Categorical Data and
Measurement Data
When you analyze data, it is important to know whether it is qualitative or quantita-tive. Categorical data are qualitative and can be split into discrete categories. Measure-ment data or numerical data are quantitative because they are continuous and do not fall into discrete categories.
Prep For
TEST-TAKING TIP
Just before taking a test, try to avoid talking about it with other students. Test anxiety can be contagious.
Win Competitive Events
10. Understanding Checking Accounts and Insurance
Organizations such as SkillsUSA offer a variety of architectural, career, and draft-ing competitions. Completing activities such as the one below will help you pre-pare for these events.
Activity To learn about checking accounts, identify the different types, the advantage(s) and disadvantage(s) of each, how to endorse checks, and how to reconcile a checkbook. Use the Inter-net to research checking account and insurance information. Write a brief paper explaining the basic information that you learn. Explain insurance policy, premium, deductible, and claim.
Go to glencoe.com for this book’s OLC for more information about competitive events.
Drafting ProblemsThe drafting problems in this chapter are designed to be completed using
board-drafting or CAD techniques. They are based on problems from Chapter 7, “Dimensioning.” If you have not yet completed the problems from that chapter, you will need to do so before attempting the following problems.
1. In Chapter 7, drafting problem 3, you created a multiview drawing of a square guide from a given pictorial. Retrieve your original multiview drawing. Use appropri-ate board or CAD techniques to change the height of the guide from 30 mm to 45 mm, as shown in Figure 21-8. Do not change the original drawing. Be sure to include a revision block on the new version.
Figure 21-8
2. In Chapter 7, drafting problem 7, you created a multiview drawing of a pipe support from a given pictorial. Retrieve your original multiview drawing. Use appropriate board or CAD techniques to replace the single bolt hole in the center top of the support with two bolt holes, aligned with the holes in the bottom of the support, as shown in Figure 21-9. To accommodate the holes, extend the base upward by .50″. Do not change the original drawing. Be sure to include a revision block on the new version.
Figure 21-9
METRIC
724 Chapter 21 Media Management
2.25
4.00
METRIC
3. In Chapter 7, Drafting Problem 8, you created a multiview drawing of a stop plate from a given pictorial. Retrieve your original multiview drawing. Use appropriate board or CAD tech-niques to change the length of the stop plate from 4.25″ to 4.00″, as shown in Figure 21-10. Move the pole support closer to the bolt holes to accommodate this change. Also, increase the width of the stop plate from 2.00″ to 2.25″. Do not change the original drawing. Be sure to include a revision block on the new version.
Figure 21-10
1. In Chapter 7, Drafting Problem 5, you cre-ated a multiview drawing of a double shaft support from a given pictorial, reproduced here as Figure 21-11. Revise the shaft support to accept three shafts. The third shaft should be at 60° to the fi rst two, so that the three holes form the vertices of an equilateral triangle. Determine the changes needed, including changes in dimensions. Consider the stability of the revised sup-port. Will the existing bolt holes be suf-fi cient, or should you add more? Use appropriate board or CAD techniques to change the shaft support. Do not change the original drawing. Be sure to include a revision block on the new version.
2. Select one of the following design prob-lems that you have already completed:
Chapter 7: Design Problem 1, 2, or 3Chapter 8: Design Problem 3Chapter 9: Design Problem 1, 2, or 3Retrieve your original set of working
drawings for the problem you select and study the drawings carefully for refi nements you might make in the original design of the product. Using revision techniques described in this chapter, make the neces-sary changes based on the refi nements you wish to make. Use appropriate board or CAD techniques to make the changes. Do not change the original drawings. Be sure to include a revision block on the new version.
3. Create a drawing using photodrafting tech-niques. Scan a photograph an simple object. Then use board-drafting or CAD techniques to give basic dimensions and other impor-tant information.
4. Research the three different methods of making a diazo print. Create a fl owchart to show the process for each method.
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Design ProblemsDesign problems have been prepared to challenge individual students or
teams of students. In these problems, you are to apply skills learned mainly in this chapter but also in other chapters throughout the text. The problems are designed to be completed using board drafting, CAD, or a combination of the two. Be creative and have fun!
Figure 21-11
Problems 725
Design an Animal Shelter
Your Project AssignmentDesign a shelter that can serve as a safe and
comfortable home for animals such as cats, dogs, or horses.
Use what you have learned in Chapters 18–21 to create a design for an animal home. Your challenge is to:
Select a pet or another animal you are familiar with or would like to know more about.
Research the design and construction of a shelter suitable for 3 or 4 animals. The shelter should be designed as a freestanding building with electricity.
List what your chosen animal needs to insure its safety and comfort. Describe the features of your structure that respond to those needs.
TIP! Cats tend to be more solitary, but dogs and horses like being part of the group. Your design should refl ect the animal’s need for social interaction.
The design of your shelter and the materials you use should refl ect the climate where you live.
Create a preliminary study of your shelter of the type you would create for client approval.
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Include a pictorial drawing and an undimen-sioned fl oor plan.
Create four elevations, one for each side of the shelter.
Create a site plan, an electrical plan, and a fully-dimensioned fl oor plan.
Applied Skills
Research and write a paragraph or two about the safety and comfort needs of your animal.
Explain your choices about the sizes of win-dow and door openings and living spaces that best accommodate your animal’s needs.
Describe the climate of the location for your shelter and explain the features of your shel-ter that accommodate inclement weather.
Create a list of materials for your shelter.
List the steps, materials, and tools you used to create the drawings for your system.
The Math Behind the ProjectThe primary math skills you will use to com-
plete this project are geometry modeling, alge-bra, and measurement. To get started, remember these key concepts, and follow this example:
Algebra—Finding Perimeter and Calculating Material Needs
Exterior and interior walls are constructed with horizontal plates and vertical studs. One bottom plate and two top plates tie together these wall structures. The amount of plate mate-rial needed for the exterior walls is equal to the perimeter of the structure times 3. To estimate the amount of 8’ length plate stock needed for a structure that measures 6' × 10', fi nd the
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Math Standards
Algebra Represent and analyze mathematical situations
and structures using algebraic symbols (NCTM)
Measurement Apply appropriate techniques, tools, and
formulas to determine measurements (NCTM)
NCTM National Council of Teachers of Mathematics
Thematic ProjectUNIT 4
726 Chapter 21 Media Management
perimeter in feet and multiply by 3. The for-mula for fi nding the perimeter of a rectangle is P = 1l + 2w where l is length and w is width. Therefore:
P = 2 × 10 + 2 × 6
TIP! When solving a problem like the one above, use order of operations to decide which calculations to make fi rst, second, and so on.
Algebra—Estimating MaterialsTo fi nd the number of studs you need for
the exterior walls of your shelter, divide the
perimeter of the shelter by the on-center dis-tance between each stud.
TIP! When performing mathematical operations with measurements, make sure that you are using the same units.
For example, if your shelter is 6’ × 10’, the perimeter is 32 feet. Since there are 12 inches in a foot:
32 × 12 = 384 inches384 ÷ 16 = 24 studs
When estimating materials for a construction job, it is a good idea to add a factor for waste. In the case of lumber, 15% is appropriate:
24 × 115% = 27.6 ~ 28 studs
Zoo DesignA zoo’s main purpose is to provide a healthy and
comfortable habitat for animals while allowing the pub-
lic to safely view them. Although all zoos share this same
purpose, how their animal exhibits are designed diff ers.
The diff erences in design depend on the size and
age of the zoo, the types of animals on display, and
the zoo’s mission. Most zoos today are dedicated to
nurturing our understanding of the natural world
and to enhancing the viability of endangered spe-
cies. Today’s zoos, aquariums, and wildlife parks aim to
house animals in a naturalistic setting without obvious
enclosures.
Research Activity Find out more about the factors
that go into the design of a zoo. What are some safety
features designers use in their plans? What environ-
mental factors do designers need to consider? Look
at the design of famous zoos, or zoos you have visited.
Bonus! Incorporate the information you fi nd into
your design of an animal shelter.
Unit 4 Thematic Project 727Tim Bird/Corbis
UNIT 4 Thematic Project
Project Steps:
Design For the Environment
STEP 1 Research
Find out about the habits of the animal you have chosen. How do they relate to each other and to humans? Are they social animals?
Are your animals curious or fearful? Are they playful? How do they deal with boredom and stress?
Find out more about different types of dog and cat houses or horse stables. List sources for and costs of materials you need to build one.
Calculate the cost of the materials you will need.
TIP! Determine if there are any similar animal homes nearby. Make an appointment to visit the site and discuss the design with those who created it.
STEP 2 Plan
Defi ne and write out your overall goal for this project.
Gather the appropriate supplies and tools for board drafting.
Set up your drawing fi le with AutoCAD.
Refer to the Math Concepts on the previous page, or go to glencoe.com for this book’s OLC for more informa-tion on the math concepts used in this project.
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STEP 3 Apply
Make a pictorial drawing and sketch a fl oor plan of your animal shelter.
Create a set of working drawings including a site plan, four elevations, an electrical plan, and a fully-dimensioned fl oor plan.
TEAMWORK Collaborate: Ask a classmate to review the design of your shelter before you continue. Ask for feedback on the technical aspects of your drawing as well as the overall concept.
STEP 4 Present
Prepare a presentation combining your research with your completed drawings using the checklist below.
Presentation ChecklistDid you remember to…
state your objectives for your shelter?
describe the features of your shelter and how they relate to the animals’ needs?
show and discuss your plan?
explain the process you used to create the shelter and what you hope to achieve with it?
explain how you created your pictorial and working drawings?
demonstrate the basic sketch or CAD drawing?
review the drafting principles involved in completing your system plan?
explain any problems you encountered and how you overcame them?
turn in your research and planning notes to your teacher?
Preparing a Multimedia PresentationTo prepare a multimedia presentation for your portfolio, you will need access to a computer with PowerPoint, Keynote, or other presentation application. Use this software to create a slide show describ-ing the entire process you employed in the execution of your animal shelter project.
Explain the Big Picture: Order your presentation chronologically to show how your project unfolded from conception, to planning, to construction, to problem solving and revision, and, fi nally, to comple-tion. You might bracket your pre-sentation with “before” and “after” images of the building site.
Showcase Your Work: Photograph or scan examples of preliminary sketches and drawings, and working drawings to showcase your skills. Include fi rst drafts as well as fi nishes to show your work process.
Add Music, Narration, and Video: Choose suitable music to intro-duce sections or your presenta-tion. Include voice-over narration describing how you dealt with chal-lenges at each step along the way. If possible, include live-action video of your completed project.
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STEP 5 Build Your Portfolio
The purpose of a portfolio is to showcase your education and examples of your work and accomplishments.
Organize your drawings in a manner that will show your ideas well.
Attach a written introduction and a descrip-tion of your design.
STEP 6 Evaluate Your Technical
Skills
Assess yourself before and after your presentation.
Is your research thorough?Did you plan your steps carefully?Did you organize your visuals so that they showcase your ideas?Is your presentation creative and effective?During your presentation, do you make eye contact and speak clearly enough?
Rubrics Go to glencoe.com to this book’s OLC for a printable evaluation rubric and Academic Assessment.
