Model G0740 (Mfg. Since 11/12)
-77-
The goal of adjusting the gib screws is to remove
sloppiness or "play" from the ways without over-
adjusting them to the point where they become
stiff and difficult to move.
In general, loose gibs cause poor finishes and
tool chatter; however, over-tightened gibs cause
premature wear and make it difficult to turn the
handwheels.
Important: Before adjusting the gibs, loosen the
locks for the device so that the gibs can freely
slide during adjustment, then lubricate the ways.
The gibs are tapered and held in position by a
screw at each end. To adjust the gib, turn one
screw
1
⁄4 turn clockwise and the other screw
1
⁄4
turn counterclockwise, so both screws move in
the same direction and the same amount. Test
the feel of the sliding component by turning the
handwheel, and adjust the gib screws as neces-
sary to make it tighter or looser.
The gib adjustment process usually requires some
trial-and-error. Repeat the adjustment process as
necessary until you find the best balance between
loose and stiff movement. Most machinists find
that the ideal gib adjustment is one where a small
amount of drag or resistance is present, yet the
handwheels are still easy to move.
After a long period of time, you may find that
the leadscrew develops a small amount of end
play. This end play can be removed with an easy
adjustment.
Tools Needed: Qty
Hex Wrench 3mm .............................................. 1
Wrench 24mm .................................................. 1
To remove leadscrew end play:
1. DISCONNECT LATHE FROM POWER!
2. Loosen the two set screws in the leadscrew
end nut (see Figure 115).
3. Engage the half nut with the leadscrew.
4. Use the handwheel to move the carriage
slightly toward the tailstock, then tighten the
end nut at the same time until the end play is
removed.
5. Retighten both set screws.
Figure 115. Leadscrew end nut.
End Nut
& Set Screws
Gib AdjustmentLeadscrew End Play
Adjustment
