MILLING MACHINE OPERATIONS - OD1644 - LESSON 1/TASK 1
(3)
Checking Gib Adjustments.
(a)
Gib adjustments should-only be made by those who are thoroughly
acquainted with the operation of the machine. In general, all of the gibs
should be tight enough to eliminate any and all play, but not so tight that
there will be a heavy drag on the working parts. Gibs that are too loose
will result in inaccurate work; gibs that are too tight will cause severe
wear and strain on the operating mechanisms.
(b)
The gibs are properly adjusted at the factory.
When readjustment
becomes necessary, proceed as follows: The table gib is adjusted by means
of two shouldered screws located on each end of the saddle.
By first
loosening one and then tightening the other, the taper gib may be adjusted
as needed. The saddle and knee gibs are adjusted in a similar manner.
(c)
The ram gib is adjusted by two adjusting screws. The front and the
end screw are the adjusting screws. To adjust the gib, the ram stops must
first be removed.
These stops are located on the bottom of the ram.
To
remove the stops, loosen the set screws, which are located on the front and
back end of the column, and turn both screws on the gib an equal amount.
After proper adjustment has been accomplished, retighten the set screws in
the column to hold the adjustment and then replace the ram stops.
(4)
Table Feed Screw. Backlash in the table feed screw is adjusted by an
adjustable bronze feed screw nut that is located at the left hand end of the
saddle. This nut is located in the saddle mechanism just above the saddle
binder.
To make any desired adjustment, first loosen the check nut and
insert a pin in any of the many holes around the flange of the nut. Then
turn the screw in either direction until the backlash is from 0.002-inch to
0.005-inch.
After you have completed this adjustment, tighten the check
nut.
(5)
Saddle Feed Screw. The saddle feed screw is adjusted by means of a
bronze adjusting nut. This adjusting nut is located in the rear end of the
bracket which is used to carry the screw, located under the saddle.
To
adjust the feed screw, remove the plate from the left side of the knee.
Then loosen the two Allen screws that holds the bronze
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