45.159
Figure 3-9.-Drawing a circle in ink.
circles. (See fig. 3-9, view A.) If the pen is not
perpendicular to the paper, ink will not flow
properly. To draw large circles, insert the
extension bar in the pen or pencil leg, as shown
in figure 3-9, view B. When the extension bar is
used to draw large circles, the process of using
the compass with only one hand becomes
awkward. You should use both hands, as shown
in figure 3-9, view B.
Use of the French Curve
The french curve is used to draw a smooth line
through predetermined points. After the points
are plotted, a light pencil line should be sketched
to connect the points in a smooth flowing line.
To draw the finished line over the freehand line,
match the various parts of the french curve to
various segments of the freehand curve. Avoid
abrupt changes in curvature by placing the short
radius of the french curve toward the short radius
portion of the line to be drawn. Change your
position around the drawing board when
necessary so that you can work on the side of the
french curve that is away from you. You should
avoid working on the “under” side of the french
curve. Place the french curve so that it intersects
at least two points of the line. When drawing the
line along the edge of the french curve, stop short
of the last point intersected. Then move the french
curve along to intersect two or three more points
and make sure that the edge of the curve connects
smoothly with the line already drawn. When
using the irregular curve, you can draw a perfectly
smooth curved line by plotting enough points (the
Figure 3-10.-Use of the french curve.
3-8
