Auto-Downfeed; Tapping Downfeed - Grizzly G0751 Owner's Manual

6. rotate mode selection switch on control
panel to drilling/Milling position.
7. start spindle rotation and use fine downfeed
handwheel (J) to control spindle travel.
Note: Use the fine downfeed graduated dial
(I) and the attached thumb screw to measure
the relative amount of spindle travel.

Auto-Downfeed

the auto-downfeed feature uses headstock gears
to control powered downfeed in rates of 0.004,
0.007, and 0.010 inches per spindle revolution.
To use auto-downfeed:
1. Make sure spindle is completely stopped.
2. Loosen depth graduated dial lock handle (G).
this will disengage depth graduated dial from
the operation.
3. rotate auto-downfeed on/oFF knob (A) to
on position.
4.
rotate auto-downfeed rate selector knob (b)
clockwise to desired downfeed rate.
5.
Loosen coarse handle lock-down thumb
screw (E) and pull coarse downfeed handles
(F) away from headstock.
6.
rotate mode selection switch on control
panel to drilling/Milling position.
When using auto-downfeed, the spindle will
not automatically stop or reverse when it
reaches the bottom depth of travel. To avoid
machine damage, manually stop spindle
rotation before this happens.
7. start spindle forward rotation to engage the
auto-downfeed.
8. When desired depth of spindle travel is
reached, stop spindle travel.
9. push coarse downfeed handles toward head-
stock and use them to return spindle to top.
Model G0751 (Mfg. Since 1/13)

Tapping Downfeed

tapping downfeed allows the downward spiraling
of the tap to control spindle travel. the depth is
controlled by adjusting the tapping limit stops (C)
in relation with the tapping limit switches (D).
To use tapping downfeed:
1. Make sure spindle is completely stopped.
2. rotate the auto-downfeed on/oFF and auto-
downfeed rate selector knobs to the oFF
position.
3. adjust depth graduated dial (H) to allow for
maximum spindle travel and tighten depth
graduated dial lock handle (G) to secure it.
4. push coarse downfeed handles (F) toward
headstock and tighten coarse handle lock-
down thumb screw (E) to hold them in place.
5. Use a 5mm hex wrench to adjust tapping limit
stops (C) in relation to tapping limit switches
(D).
— the shorter limit stop is used to reverse
spindle rotation when desired depth is
reached. this will happen when this limit
stop contacts outer limit switch.
— the longer limit stop is used to stop spindle
rotation for repetitive operations. this will
happen when this limit stop contacts inner
limit switch. adjust limit stop in relation to
inner limit switch so that spindle rotation
stops when the tap is no longer engaged
with workpiece.
6.
rotate mode selection switch on control
panel to tapping position.
Note: Position tap just slightly above the
workpiece when the spindle is at the top most
position. This will prevent the tap breaking
when spindle rotation is started.
7.
start spindle forward rotation.
8. Use coarse downfeed handles to slowly lower
tap into workpiece until it engages workpiece
and the downward spiraling action of tap
controls spindle travel, then release manual
pressure on coarse downfeed handles.
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