23
AUXILIARY VIEWS & VISUALIZATION TECHNIQUES FOR MULTIVIEW DRAWINGS
AUXILIARY VIEWS & VISUALIZATION TECHNIQUES FOR MULTIVIEW
DRAWINGS
Three Principal Projection Planes
Common Planar Surfaces of Objects
1. Normal Surfaces 2. Inclined Surfaces 3. Oblique Surfaces
1. Normal Surfaces
A normal surface is a planar surface that is orthogonal to the 3 principal planes of projection.
2. Inclined Surfaces
An inclined surface is a normal surface that has been rotated about 1 principal axis. It is perpendicular to 1 principal projection plane and inclined to the other 2.
3. Oblique Surfaces
An oblique surface is a planar surface that has been rotated about 2 principal axes. It is inclined to all 3 principal projection planes.
AUXILIARY VIEW DRAWINGS
3–View Multiview Drawing
The true shape of the inclined face (A) cannot be seen in the front view and is foreshortened in the side and top views. To show the true size and shape of this face, an additional, or auxiliary view must be added to these three views.
TOP
FRONT RIGHT
Inclined Surface (A)
Auxiliary View Projection Theory (Glass Box Theory)
Primary Auxiliary View
The primary auxiliary view is projected parallel and perpendicular to the inclined plane in the view where the inclined plane is seen as an edge.
Auxiliary View: Three Cases
Partial Multi-Auxiliary-View
• This auxiliary view is a partial view since the top and left faces are not shown on it.
• The top view is a partial view as well.
Complete Multi-Auxiliary-View
Secondary Auxiliary View
To draw the true size and shape of an oblique plane, a secondary auxiliary view is required. First, a primary auxiliary view is projected from one edge of the oblique plane in one of the views of the multiview, and then a secondary auxiliary view is projected from the primary auxiliary view.
Visualization Techniques for Multiview Drawings
Visualization Approaches to Deciphering Multiview Drawings
1. Draw pictorials 2. Reduce complex shapes to primitive shapes 3. Label surfaces 4. Label Vertices 5. Create 3-Dimensional Models 6. Solve Missing Lines & Missing View
Problems
Visualization Approaches to Deciphering Multiview Drawings
1. Draw a Pictorial
ISOMETRIC
Visualization Approaches to Deciphering Multiview Drawings
2. Reduce Complex Shapes to Simple Shapes
Visualization Approaches to Deciphering Multiview Drawings
3. Label Surfaces
T
F
T
T
F
F R
R
R
T
R F
Visualization Approaches to Deciphering Multiview Drawings
4. Label Vertices
3
2
1
4
5
1
3
2
4,5
1,2
5
4
3,2
Visualization Approaches to Deciphering Multiview Drawings
5. Create a 3-Dimensional Model
Visualization Approaches to Deciphering Multiview Drawings 6. Solve Missing Lines & Missing View Problems
arrrrg
