Tangency, Continued
To draw an arc
To draw an arc tangent to two arcs, follow this table:
tangent to two
arcs
Step
Action
1
Given arcs with centers A and B, and a required radius R, draw arcs
parallel to the given arcs and at a distance that equals R.
2
Label the intersection of these arcs C since this is the center of the
required tangent arc.
3
Draw lines from the centers A and B to C to locate points of
tangency T.
4
Draw the required arc with a radius of R to the points of tangency.
Figure 2-31 shows the process of drawing a tangent arc to two arcs.
Figure 2-31.
—Drawing an arc
tangent to two arcs.
Clearly this section does not cover all situations of tangency but shows that
the problems have mathematical solutions.
Refer to texts in basic drafting for
more complete coverage of tangential problem solving.
2-32
