-45-
Model M1112 (For Machines Mfd. Since 12/20)
SE
RV
IC
E
Figure
62
.
Saddle lock bolt and saddle gib
screws.
Saddle Lock
Bolt
Saddle Gib and Saddle Lock
The saddle is supplied with a square head bolt (
Figure
62
)
on the front right hand side of the slide. This bolt
locks the saddle in place for increased rigidity when
making face cuts. Before making adjustments to the
saddle gib, make sure that this bolt is loose by turning it
counterclockwise.
It is important that this gib stay properly adjusted. A
loose gib will cause finish problems in a workpiece. A gib
adjusted too tightly will cause premature half-nut wear.
The gib for the saddle is located on the bottom of the
back edge of the slide (
Figure 62
). The tension on this
gib is maintained by four set screws with jam nuts. By
loosening the jam nuts and tightening the set screws, the
gib will tighten. Loosening the set screws will loosen the
gib. The gib strip is properly adjusted when a slight drag
is felt while moving the apron. Do not over-tighten.
It is important the four set screws are tightened evenly.
When tightening the jam nuts, hold the set screw in
position with a hex wrench.
Half-Nut Adjustment
If the half-nut threads do not fully mesh with the
leadscrew, the quality of the workpiece threads may
suffer. If the half-nut clamps the leadscrew too tightly,
rapid half-nut wear and a non-release or delayed half-nut
release condition could occur, which can cause chuck
and carriage crash. It is far better to have a half-nut that
clamps slightly loose rather than having it clamp too tight.
To adjust the half-nut, do these steps:
1.
Engage the half-nut lever, loosen the thread dial cap
screw, and rotate the dial out of the way (
Figure
63).
2.
Loosen the lock nuts, and while rocking the carriage
handwheel back and forth slightly, tighten the
adjustment screws until snug to seat the gibs.
3.
Back out each screw
1
⁄
4
turn and tighten the lock
nuts.
4.
Verify the half-nut lever easily clamps and un clamps
on the lead screw without binding.
REMEMBER
,
threading cuts that are too deep or have a feed rate
that is too fast may prevent or delay half-nut lever
disengagement and cause a carriage crash.
Figure
63
.
Half-nut gib adjustment
location.
Thread Dial
Swung Out
of Way
Lead Screw
Half-Nut
Thread Dial Pivot
Cap Screw
Half-Nut
Adjustment
Screws and
Lock Nuts
