Southbend SB1046PF - Manual (Page 79)

SERVICE
For Machines Mfg. Since 3/11 Turn-Nado ® Gearhead Lathes
-77-
S E R V I C E
Cross Slide
Tools Needed: Qty
Hex Wrench 3mm .................................................1
Hex Wrench 5mm ................................................1
The cross slide backlash is adjusted by loosening
all four cap screws shown in Figure 112, then
tightening the center set screw. This will push
down on a wedge and force the leadscrew nut
apart, taking up lash between the nut and
leadscrew.
Backlash Adjustment
Backlash is the amount of free play felt while
changing rotation directions with the handwheel.
This can be adjusted on the compound rest
and cross slide leadscrews. Before beginning
any adjustment, make sure that all associated
components have been cleaned and lubricated.
Compound Rest
Tools Needed: Qty
Hex Wrench 3mm .................................................1
The compound rest backlash is adjusted by
tightening the set screws shown in Figure
111. When these screws are adjusted against
the leadscrew nut, they offset part of the nut to
remove play between the nut and leadscrew.
Figure 111. Compound rest backlash adjustment set
screws.
Set Screws
Reducing backlash to less than 0.002" is
impractical and can lead to accelerated wear
of the wedge, nut, and leadscrew. Avoid the
temptation to overtighten the backlash set
screw while adjusting.
To adjust the backlash, rock the handwheel back
and forth, and tighten the screws slowly until
the backlash is approximately 0.002"–0.003", as
indicated on the graduated dial.
If you end up adjusting the nut too tight, loosen
the set screws, tap the compound rest a few
times with a rubber or wooden mallet, and turn
the handwheel slowly back and forth until it
moves freely—then try again.
To adjust the backlash, remove the compound
rest and loosen the four cap screws. Then, rock
the cross slide handwheel back and forth, and
tighten the set screw slowly until the backlash is
at approximately 0.002"–0.003" as indicated on
the graduated dial.
If you end up adjusting the nut too tight, loosen
the set screw, tap the cross slide a few times
with a rubber or wooden mallet, and turn the
handwheel slowly back and forth, until the
handle turns freely—then try again.
Remember to re-tighten the four cap screws
when you are finished.
Figure 112. Cross slide backlash adjustment screws.
Set
Screw
Cap Screws