South bend SB1049F, Manual

Page: 61 / 136

For Machines Mfg. Since 5/11 13" Heavy 13
®
Gearhead Lathe
-55-
O P E R A T I O N
Alternate Configuration
The alternate end gear configuration is used
when cutting modular or diametral threads. The
57T end gear is positioned on the outside so that
it meshes with the 44T transposing gear instead
of the 56T gear, as illustrated in Figure 74.
Figure 74. Alternate end gear configuration.
57T
44T
24T
Modular and Diametral
Pitch Turning
56T
Configuring End Gears
Tools Needed Qty
Hex Wrench 6mm .................................................1
Wrench 22mm .......................................................1
To configure the end gears:
1. DISCONNECT LATHE FROM POWER!
2. Remove the headstock end gear cover.
3. Remove the cap screw, lock washer, and flat
washer from the bottom 57T end gear (see
Figure 75).
Figure 75. End gear components.
Pivot
Hex Nut
Cap Screw,
Washers & Spacer
4. Loosen the pivot arm hex nut shown in
Figure 75, then swing the pivot arm to the
left so that 44T/56T gears are away from the
57T gear. Hand tighten the hex nut to keep
the arm in place.
5. Use a stiff brush and mineral spirits to clean
away the debris and grime from the gears
and shafts, then lubricate these devices as
instructed in the End Gears lubrication
subsection on Page 70.
6. Making sure to keep the key seated in the
shaft, remove the spacer and the 57T gear,
then re-install them as follows:
— For the standard end gear configuration,
slide the 57T gear on first, then the spacer
on the outside.
— For the alternate end gear configuration,
slide the spacer on first, then the gear.
7. Re-install the cap screw, lock washer, and
flat washer you removed in Step 3 to secure
the spacer and 57T gear.
Note:
DO NOT overtighten the cap screw—
it merely holds the gear in place.
Overtightening it will make it harder to
remove later and may restrict the rotation of
the gears.
8. Slide the pivot arm back so that either the
44T or the 56T meshes with the 57T gear,
then retighten the pivot arm hex nut.
Note: Make sure to keep approximately 0.002"
play between the gears.
9.
Replace and secure the end gear cover before
connecting the lathe to power.