Woodstock M1109 owner manual Service, Cross Slide Backlash

M1109 Combo Lathe/Mill

SERVICE

SERVICE

Cross Slide Backlash

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 back- lash 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 59. 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 feed 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 dial.

Note: Reducing backlash to less than 0.001" is impractical and reduces the life of the cross slide.

Cross Slide, Half-Nut,

and Compound Slide Gib

Adjustments

When adjusting these gibs (Figures 60 and 61), 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 may cause undue wear on the slide. Over-tightening may cause pre- mature wear on the slide, lead screw, and half-nut. The cross slide gib is a tapered piece of iron. When the oppos- ing front and rear gib adjustment screws are turned in opposing directions, the screws force the tapered gibs to fill the loose 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 60) loosen the jam nuts and turn the three set screws until there is slight tension felt and the gib plates are slightly preloaded against the underside of the flat-way. Tighten the jam nuts when fin- ished.

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Cross Feed

Backlash

Adjustment

Cap Screw

Figure 59. Cross slide backlash

adjustment cap screw.

Cross Slide Gib Adjustment Point

Saddle Gib Adjustment Points

Figure 60. Gib adjustment points.

Figure 61. Half-nut gib adjustment

location (thread dial is swung out of the

way for gib adjustment).