Figure 7-78.--Universal milling (head) attachment.
diameter of the arc through which the tool moves is
results in a more rigid boring operation, but the size of
also a factor. For all of these reasons you must avoid
the hole that can be bored is more limited than those
too-great of speeds to prevent vibration.
on a lathe or a drill press.
Fly cutters, which we discussed previously, can
MILLING MACHINE ATTACHMENTS
also be used for boring, as shown in figure 7-77. A fly
cutter is especially useful to bore relatively shallow
Many attachments have been developed that
hales. The cutting tool must be adjusted for each
increase the number of jobs a milling machine can do,
depth of cut.
or that make such jobs easier to do.
The speeds and feeds you should use to bore on a
UNIVERSAL MILLING ATTACHMENT
milling machine are comparable to those you would
use to bore on a lathe or drill press. They also depend
The universal milling (head) attachment, shown
on the same factors: hardness of the metal, kind of
in figure 7-78, is clamped to the column of the milling
metal in the cutting tool, and depth of cut. The boring
machine. The cutter can be secured in the spindle of
bar is a single-point cutting tool; therefore, the
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