Line Conventions, Continued
Extension lines are thin lines that extend from the object outline or point on
the object to a place outside the image area. Extension lines define areas for
dimensions. You should leave a 1/16" gap between the object outline or
point on the object and the beginning of the extension line.
project 1/8" beyond the outermost dimension line. Extension and dimension
lines are drawn at right angles to each other.
Figure 3-12 shows extension and dimension lines.
Figure 3-12.Extension and dimension
When extension lines must cross each other or object outlines, break the
Figure 3-13 illustrates the correct and incorrect use of extension lines.
Figure 3-13.Extension lines drawn correctly and
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