Figure 2-19.--Locating the center of round stock.
Figure 2-17.--Laying out a 45-degree angle.
lines drawn with the same setting, and from the same
true edge of the work, will be parallel lines.
edge of the stock, as shown in figure 2-17. Draw the
Use the center head and rule, as illustrated in
line along either edge of the blade. The line will form
figure 2-19, to locate the center of round stock. To
a 45-degree angle with the edge of the stock against
find the center of square and rectangular shapes,
which the squaring head is held.
scribe straight lines from opposite corners of the
workpiece. The intersection of the lines locates the
To draw angular lines with the protractor head of
center.
a combination square, loosen the adjusting screw and
rotate the blade so the desired angle lines up with the
index mark on the body of the protractor head. The
LAYING OUT CIRCLES AND
setting shown in figure 2-18 is 60°. Tighten the screw
IRREGULAR LINES
to hold the setting.
Circles or segments of circles are laid out from a
Hold the body of the protractor head in contact
center point. To ensure accuracy, prick-punch the
with the true edge of the work with the blade resting
center point to keep the point of the dividers from
on the surface. Scribe the lines along the edge of the
slipping out of position.
blade on the surface of the work. The angle set on the
To lay out a circle with a divider, take the setting
scale determines the angle laid out on the work. All
of the desired radius from the rule, as shown in
figure 2-20. Note that the 3-inch setting is being
taken AWAY from the end of the rule. This reduces
the chance of error as each point of the dividers can be
Figure 2-18.--Laying out angular lines.
Figure 2-20.--Setting a divider to a dimension.
2-10