Machinery Repairman

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closely as possible to the cutter. Make sure
that the work and the vise will clear all parts
of the machine.
Install the arbor nut and tighten it finger tight
only.
Position the overarm and mount the arbor
support.
After supporting the arbor, tighten the arbor
nut with a wrench.
Set the spindle directional control lever to
give the required direction of cutter rotation.
Determine the required speed and feed, and
set the spindle speed and feed controls.
Set the feed trip dogs for the desired length of
cut and center the work under the cutter.
Lock the saddle.
Engage the spindle clutch and pick up the cut.
Pick up the surface of the work by holding a
long strip of paper between the rotating cutter
and the work; very slowly move the work
toward the cutter until the paper strip is
pulled between the cutter and the work.
Keep your fingers away from the cutter. A
rotating milling cutter is very dangerous.
Move the work longitudinally away from the
cutter and set the vertical feed graduated
collar at ZERO.
Compute the depth of the roughing cut and
raise the knee this distance.
Lock the knee, and direct the coolant flow on
the work and on the outgoing side of the
cutter.
Position the cutter to within 1/16 inch of the
work, using hand table feed.
Engage the power feed.
After completing the cut, stop the spindle.
Return the work to its starting point on the
other side of the cutter.
Raise the table the distance required for the
finish cut.
Set the finishing speed and feed, and take the
finish cut.
7-31
26. When you have completed the operation,
stop the spindle and return the work to the
opposite side of the cutter.
27. Deburr the work and remove it from the vise.
To machine the second side, place the work in the
vise as shown in figure 7-55, view B. Rough and
finish machine side 2, using the same procedures that
you used for side 1. When you have completed side 2,
deburr the surface and remove the work from the vise.
Place the work in the vise, as shown in figure
7-55, view C, with side 3 up. Then, rough machine
side 3. Finish machine side 3 for a short distance,
disengage the spindle and feed, and return the work to
the starting point, clear of the cutter. Now you can
safely measure the distance between sides 2 and 3. If
this distance is correct, you can continue the cut with
the same setting. If it is not, adjust the depth of cut as
necessary. If the trial finishing cut is not deep
enough, raise the work slightly and take another trial
cut. If the trial cut is too deep, you will have to
remove the backlash from the vertical feed before
taking the new depth of cut. Use the following
procedure to remove the backlash:
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Lower the knee well past the original depth
of the roughing cut.
Raise the knee the correct distance for the
finishing cut.
Engage the feed and complete your cut.
Stop the spindle.
Return the work to the starting point on the
other side of the cutter.
6. Deburr the work.
7. Remove the work from the vise.
Place side 4 in the vise, as shown in figure 7-55,
view D, and machine the side, using the same
procedure as for side 3. When you have completed
side 4, remove the work from the vise and check it for
accuracy.
This completes the machining of the four sides of
the block. If the block is not too long, you can rough
and finish mill the ends to size in the same manner in
which you milled the sides. Do this by placing the
block on end in the vise. You also may use face
milling to machine the ends.