Drawing Aids
Introduction
Lettering aids, triangles, protractors, anything that helps the draftsman create
an image, is a drawing aid. Some shops are fortunate enough to give each
worker a set of drawing aids. Other shops have to share equipment among
the workers. If your shop shares equipment among the workers, put the gear
away clean and in good repair. Keep uncommon tools in commonly
accessible places.
General care
Most drawing aids are made of plastic. Hang up drawing aids or store them
flat when they are not in use. Never cut against the edges of a drawing aid
or use them as a scraper. When a drawing aid is warped, nicked, out of true,
or broken, throw it away and get another.
Triangles
Use triangles to draw lines at various inclines to the horizontal. Two
common triangles are the 30/60- degree and the 45-degree triangle. Both of
these triangles have a 90-degree base angle. A combination of a 30/60- and a
45-degree triangle creates eleven other angles. Triangles may or may not
have an ink riser to prevent the flow of ink under the triangle edge. Plastic
triangles are the easiest to use because you can see the work through them.
Figure 2-43 illustrates the angles created when you use combinations of a
30/60- and a 45-degree triangles.
Figure 2-43. —Common angle combinations.
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