Grizzly G0492 - Manual (Page 40)

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G0492 12" X 36" Combo Lathe/Mill
SECTION 7: SERVICE
Figure 55. Gib adjustment points.
Saddle Gib Adjustment Points
Cross Slide Gib Adjustment Point
Figure 56. Half-nut gib adjustment location.
When adjusting gibs ( Figures 55 and 56), keep
in mind that the goal is to remove sloppiness in
the ways without causing the slides or half nut to
bind. Loose gibs will cause a poor finish on the
workpiece and wear the slide. Over-tightening will
damage the slide, lead screw, and half-nut. The
cross slide gib is a tapered piece of iron. When
the opposing front and rear gib adjustment screws
are turned in opposing directions, the screws force
the tapered gibs to fill the void in the way, thus
tightening the play in the cross slide. If more play
is needed turn the screws the other direction.
For the four saddle gibs, ( Figure 55) loosen the
jam nuts and turn the three set screws until slight
tension felt and the gib plates are slightly pre-load-
ed against the underside of the flat-way. Tighten
the jam nuts when finished.
Gib Adjustments
Figure 54. Cross slide backlash adjustment cap
screw.
Cross Slide
Backlash
Adjustment
Cap Screw
Backlash is the amount of play found in a lead
screw. It can be found by turning the cross slide
handwheel in one direction, and then turning the
handwheel the other direction. When the cross
slide begins to move, the backlash has been
taken up.
Note: Avoid the temptation to overtighten the
cross slide backlash screw. Overtightening will
cause excessive wear to the sliding block and
lead screw.
Backlash is adjusted by tightening or loosening
the screw shown in
Figure 54.
Cross Slide
Backlash Adjustment
This screw draws a wedge-type nut against the
lead screw and main nut. If you get it too tight,
loosen the screw a few turns and tap the cross
slide a few times with a rubber or wooden mallet.
Then turn the handle slowly back and fourth until
the handle turns freely. To readjust the backlash,
rock the handle back and fourth and tighten the
screw slowly until the backlash is at approximately
0.001" to 0.002" as indicated on the handwheel.
Note: Reducing backlash to less than 0.001"
is impractical and reduces the life of the cross
slide.