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
Inclined Surface (A)
TOP
FRONT
RIGHT
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.
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
T
R
F
R
F
T
F
T
R
F
R
Visualization Approaches to
Deciphering Multiview Drawings
4. Label Vertices
5
4
5
4
3,2
4,5
3
2
1
3
2
1
1,2
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
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