Grizzly G9249 - Manual (Page 41)

g9249 12" x 37" Belt drive gap Bed lathe
-39-
7. select the replacement gears as directed by
the feed rate or threading chart (see figure
56 for an example of positioning).
Side
View
Front
View
(% (%
('
&'%
&',
&',
&'%
('
figure 56. Change gear configuration example.
;aVc\Z
@ZnlVn
figure 57. Change gear.
8. With the flange of the gear pointing away
from the headstock (see figure 57), align the
keyway of the top change gear with the shaft
key, then completely seat the gear on the
shaft. secure it in place with the flat washer
and hex nut. do not overtighten.
9. Mount the bottom change gear in a similar
manner as the top change gear, and secure
it in place with the flat washer and cap screw.
however, you must choose the correct orien-
tation of the gear flange.
— if the bottom change gear will engage the
127t (larger) middle change gear, point the
gear flange away from the headstock.
— if the bottom change gear will engage the
120t (smaller) middle change gear, point the
gear flange toward the headstock.
NOTICE
for smooth operation and to reduce wear
of the change gears, always make sure to
clean away debris and built-up grime, then
apply a light film of multi-purpose gear
grease to the gear teeth.
10. swing the pivot bracket up to mesh the
middle change gears with the top and bottom
change gears.
Note: It may be necessary to re-position the
middle change gears on the pivot bracket
to properly mesh with the top and bottom
gears.
11. Make sure there is a backlash of 0.002"–0.003"
between the gears, then tighten the middle
change gear hex nut and the pivot bracket
hex nut.
Note: Setting the gears too tight will cause
excessive wear and noise. Setting the gears
too loose may cause slippage and gear tooth
breakage.
12. Close and secure the change gear door
before beginning operations.