Drawing Aids, Continued
Irregular
The two types of irregular curves common to a Navy Graphics shop are
curves
radius curves, sometimes called railroad curves, and french curves.
RADIUS CURVES: Radius curves are used for drawing large arcs. The
radius of these arcs are from 1 1/2 to 1,000 inches. Some radius curves have
a flat segment on one end, called a tangent.
Figure 2-46 shows radius curves.
Figure 2-46. —Radius curves.
FRENCH CURVES: Use a french curve for drawing irregular or
noncircular curves. Some french curves have an ink riser as part of their
design. If your french curves do not have an ink riser, put one on with
masking tape.
Figure 2-47 shows typical shapes for french curves.
Figure 2-47. —French curves.
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