-33-
Backlash Adjustment
Compound Leadscrew
Backlash is adjusted by tightening the set screws
shown in Figure 85. When these screws are adjusted
against the leadscrew nut, they offset part of the half
nut to remove play between the nut and leadscrew.
If you end up adjusting the half nut too tight, loosen
the set screws, tap the compound a few times with a
rubber or wooden mallet, and turn the handle slowly
back and forth until it moves freely.
To readjust the backlash, rock the handle back and
forth, and tighten the screws slowly until the backlash
is at approximately 0.025mm as indicated on the
handwheel dial.
Leadscrew End Play
Adjustment
After a long period of time, you may
fi
nd that the
leadscrew develops a small amount of end play.
This lathe is designed so that leadscrew end play can
be easily removed with adjustment.
To remove leadscrew end play :
1. Disconnect Lathe from POWER !
2. Remove the three cap screws and end cover.
3. Loosen both retaining nut set screws shown in
Figure 87.
Section 5 : Service
Set Screws
Figure 85. Compound slide backlash adjustment
set screws.
Figure 86. Compound slide backlash adjustment
set screws.
Cap Screw
Set Screw
Figure 87. Leadscrew end play adjustment.
Retainer Nut
with Set Screws
Leadscrew
Cross Slide Leadscrew
Backlash can be felt by turning the cross slide
handwheel in one direction, then turning the
handwheel the other direction, then noticing the
amount the handwheel moves while the cross slide
does not. When the cross slide begins to move, the
backlash has been taken up.
Backlash is adjusted by loosening all four cap screws
shown in Figure 86, and then tightening the center
set screw, which pushes down on a wedge and forces
the half nut apart, taking up lash in the half nut and
leadscrew. If you end up adjusting the half nut too
tight, loosen the set screw, tap the cross slide a few
times with a rubber or wooden mallet, and turn the
handle slowly back-and-forth, until the handle turns
freely.
To re-adjust the backlash, rock the handle back
and forth and tighten the set screw slowly until the
backlash is at approximately 0.025mm as indicated
on the handwheel dial.
4. Engage the half nut lever.
5. Rotate the carriage feed handwheel back and
forth slightly and tighten the retaining nut at the
same until the end play is removed.
6. Tighten both set screws and reinstall the cover.
