Views, Continued
Half sections
Cutting planes that pass halfway through an object result in a half section.
The American National Standards Institute (ANSI) recommends using
centerlines for the division line between the sectioned half and the
unsectioned half of a half-section view. Notice that in fact, by using both
centerlines you expose only one quarter of the object.
Use a half-section
view when you must show the interior of one half of the object while
retaining the exterior of the other half. This limits the useful application of
half-section views to symmetrically-shaped objects. Half sections are most
useful when used in assembly drawings. Because half sections require
symmetry and are difficult to dimension, they are not often used in detail
drawings.
Figure 3-53 shows a half-section view.
Figure 3-53.—A half section.
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