Model g8688 (Mfg. 3/09+)
-25-
carriage
the longitudinal movement of the carriage (car-
riage feed) on the Model g8688 can be controlled
both manually and automatically.
To move the carriage feed manually:
1. rotate the handwheel clockwise to move the
carriage right and rotate the handwheel coun-
terclockwise to move the carriage left.
2. Set the handwheel scale in the same manner
as described in the
cross slide instructions
on
page 25, and be sure to account for the
backlash.
Automatic carriage feed
the feed rate is based on the rotational speed of
the leadscrew which is determined by the gear
configuration in the headstock. the feed rate for
normal turning is much less than used for screw
cutting. therefore, it is very important to pay close
attention to the gear combinations you have cho-
sen before engaging the auto feed lever. the lathe
comes from the factory set up for normal turning.
gear changes for thread cutting will be covered
later.
crAsHING HAzArD! pay close attention
to feed rate before engaging power feed.
be alert and ready to shut Off power feed,
otherwise carriage will crash into rotat-
ing spindle, causing damage and possible
injury!
To use the automatic carriage feed for normal
turning:
1. use the manual feed handwheel to position
the carriage to your desired starting point and
set the scale on the handwheel to “0”.
2. Set the lead screw ForWard/nEutral/
rEVErSE lever to ForWard.
3. Set the ForWard/oFF/rEVErSE toggle to
ForWard.
4. turn the VariaBlE SpEEd Control dial
to the desired rpM.
5. Move the feed lever down to engage the
half-nut, which in turn, makes the automatic
carriage feed active (see
figure 24).
figure 24. Feed lever.
6. lift the feed lever to stop the automatic car-
riage feed.
the automatic carriage feed can also oper-
ate in the rEVErSE direction by changing the
leadscrew direction after turning the lathe
Off.
