Machinery Repairman

Figure 6-69.—Knurled impressions.
shown in figure 6-69, by disengaging the clutch after
the work has revolved three or four times and by
backing the knurling tool away from the work.
If the knurls have double tracked, as shown in
figure 6-69, move the knurling tool to a new location
and repeat the operation. If the knurl is correctly
formed, engage the spindle clutch and the carriage
feed. Move the knurling rollers into contact with the
correctly formed knurled impressions. The rollers
will align themselves with the impressions. Allow the
knurling tool to feed to within about 1/32 inch of the
end of the surface to be knurled. Disengage the
carriage feed and with the work revolving, feed the
carriage by hand to extend the knurl to the end of the
surface. Force the knurling tool slightly deeper into
the work, reverse the direction of feed and engage the
carriage feed. Allow the knurling tool to feed until
the opposite end of the knurled surface is reached.
Never allow the knurls to feed off the surface.
Repeat the knurling operation until the diamond
impressions converge to a point. Passes made after
the correct shape is obtained will result in stripping
away the points of the knurl. Clean the knurl with a
brush and remove any burrs or sharp edges with a file.
When knurling, do not let the work rotate while the
Figure 6-70.—Rings on a knurled surface.
6-40
Figure 6-71.—Toolpost grinder.
tool is in contact with it if the feed is disengaged.
This will cause rings to be formed on the surface, as
shown in figure 6-70.
SETTING UP THE TOOLPOST GRINDER
The toolpost grinder is a portable grinding
machine that can be mounted on the compound rest of
a lathe in place of the toolpost. It can be used to
machine work that is too hard to cut by ordinary
means or to machine work that requires a very fine
finish. Figure 6-71 shows a typical toolpost grinder.
The grinder must be set on center, as shown in
figure 6-72. The centering holes located on the
spindle shaft are used for this purpose. The grinding
wheel takes the place of a lathe cutting tool; it can
perform most of the same operations as a cutting tool.
Cylindrical, tapered, and internal surfaces can be
ground with the toolpost grinder. Very small grinding
Figure 6-72.—Mounting the grinder at center height.