6. Milling Machine Adjustments

6. Milling Machine Adjustments
a. Vertical Milling Machine.
(1) Adjustments.
(a) Proper gib adjustment procedures must be done after 40 hours on new mills.
(b) Each 700 and 800 series of mills have three gibs. One at the front dovetail of
the table, one on the left dovetail of the saddle, and one on the left dovetail of the
knee. Each gib is supplied with two lock or adjustment screws. The table gib has a
lock screw on the right front of the saddle and the adjusting screw on the left front
of the saddle.
(c) The saddle gib is at the rear of the saddle on the left side, while the adjusting
screw is at the front of the saddle on the left side. The knee gib lock screw is on
the bottom of the knee on the left side and the adjusting screw is on the top on the
left side.
(d) To adjust the table gib, loosen the table gib lock screw several turns and
tighten the adjusting screw on the opposite side of the table until the gib is
pressing against the table dovetail. Tighten the lock screw. (Do not tighten the lock
screw too tight as it distorts the gib.) Run the table back and forth and check the
table for drag. To adjust the saddle and knee, use the same procedures as above.
(2) Adjustments With The Dial Indicator.
(a) When checking the gibs with a dial indicator, the following checks should be
made: (Use figure 22 as reference.)
(b) With the dial indicator mounted, as in Position 3, the table can be tested for
looseness by pulling back and forth on the end of the table. Anything over
0.0015-inch is too much and requires the gibs to be adjusted, also the table
should snap back to the "0" reading each time after the table is released.
(c) To check the saddle gib, the indicator should be mounted as in Position 7 and
the same tolerance should exist here.
(d) The knee gib will be checked as shown, with the dial indicator in Position 5,
by grasping the table and lifting up and pushing down. The reading of deflection
here should not be more than 0.0003 of an inch.
(e) As a final check, set the dial indicator on Position 2 and run the table to its
extreme right and left positions. The indicator runout should not be more than
0.0015 of an inch.
(3) Quill Feed Clutch. Adjustment of this clutch is as follows: