# Grizzly G9972Z questions about feed and cross feed control.



## BillSmith (Nov 8, 2019)

Good morning,

Well I've been watching for a SB heavy 10 in my area for at least 3 months now and no luck.  Now I'm looking at the G9972z as a second choice.  After reading contradicting information I've now been able to confirm that it has powered crossfeed but I have another question about reversing the feed direction.  I need to be able to reverse the feed direction with the split nut remaining in the same thread because of a semi-DIY electronic threading mod that requires it to cut metric.  Can I reverse the feed and keep it in the same thread simply by using the black R L switch next to the emergency stop?  I'm not trying to cut LH threads, just want to stay in the tread instead of backing out, moving it with the wheel and starting the next cut based on timing.  Thanks!


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## pdentrem (Nov 8, 2019)

There will be too much backlash in the leadscrew and halfnuts to keep the tool in contact. Even our $50k CNC machines retract the tool on the return to the start position.


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## BillSmith (Nov 8, 2019)

I'm sorry, now that I reread my post, I should have said keep it in time.  It will not actually be run backwards while it is in contact with the thread.


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## Mitch Alsup (Nov 8, 2019)

The standard method is 
a) close the 1/2 nut
b) set tool depth on cross slide (to zero)
c) set DoC on compound slide
d) run it forward
e) back out the cross slide
f) run it backwards
repeat at (b)


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## BillSmith (Nov 8, 2019)

Yes, I understand that.  I'm wondering if on the lathe referenced I can:
1)  Cut the first thread.
2) Turn off the spindle at the end of the cut via the switch.
3) Back the cross slide away from the cut
4) Reverse the direction of the spindle on the switch from off to reverse.
5) The cross feed returns to the start of the next cut under power, turn the spindle off
6) set the cutter to the correct depth for the next cut.
7) Move spindle switch from off to forward.
8) Cut the new thread with proper timing
During the entire process the 1/2 nut is never released.


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## MontanaLon (Nov 8, 2019)

Yes, that is how it works. Just be sure to reverse beyond the start point so the half nut play is taken up before the tool engages the work.


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## BillSmith (Nov 8, 2019)

Thank you very much.  It just occurred to me that black whatever day is coming.  Dang.


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