When revolving an object perpendicular to the front plane of projection, the
depth dimensions in the top and side views remain true and the size and
shape of the front view remain the same. The top and bottom views are now
oblique to the horizontal plane of projection foreshortening the length
dimensions. The side surfaces are now oblique to the profile plane causing
vertical dimensions to foreshorten. The amount of foreshortening works
itself out as you project the different views.
Figure 3-47 shows a 30-degree revolution perpendicular to the front plane of
Figure 3-47.Revolving the front plane of projection of an object 30
aegrees from the perpendicular.
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