# G0752Z/G0602 Compound rest adjustments



## WobblyHand (Dec 4, 2021)

Trying to adjust the backlash on the compound rest on my G0752Z.  From the instructions, it says to loosen the set screw 231 and turn the threaded collar 230. Did that, but can't seem to do better than 0.009" backlash.  Grizzly says to not try to do better than 0.003", but I am far from that!  The handle gets harder to turn but the backlash doesn't improve.  I used a dial indicator to check when the compound actually moved.  Is this the right way to measure it?

Also, the compound graduated dial seems loose, so loose it nearly spins freely.  The dial on the compound is a lot looser than the one on the cross slide.  Is there an adjustment for the compound dial looseness?  Any suggestions on how to get it less _free wheeling_?


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## fitterman1 (Dec 4, 2021)

I've got 0.008" lash in mine. Your  threaded spindle runs in a round nut which is just drilled and tapped radially for the thread of the spindle. If that's worn, that's the best you'll get.


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## benmychree (Dec 4, 2021)

Compound rest backlash is really not an issue.


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## fitterman1 (Dec 4, 2021)

I have a thread called " my workman, my way ", here somewhere and it shows what i made to overcome this, i still haven't installed it, been too busy, but its the only way I have found to overcome cheap engineering.
As Ben says, its not a serious issue, and it hasn't really bothered me but if it bothers you, try that mechanism and you'll get better than 003" backlash.
Cheers Alby


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## RJSakowski (Dec 4, 2021)

I checked my compound  backlash and it is .005".  There are two components to the backlash.  The play in the thrust bearing and the fit of the lead screw. You can remove almost all the thrust bearing play but as far as I know, there is no adjustment for the compound nut.


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## fitterman1 (Dec 4, 2021)

Heres the link if you're interested.








						My Workman (G0602), my way
					

This is my experience with what in Australia is called a Workman 250 x 550 lathe. It is exactly the same as what is also known as a G0602 as supplied by Grizzly in the US and comes under other names in different parts of the world. Gday viewers my name is fitterman1 and I live in Australia down...




					www.hobby-machinist.com
				



Got to post number 29


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## WobblyHand (Dec 4, 2021)

fitterman1 said:


> I've got 0.008" lash in mine. Your  threaded spindle runs in a round nut which is just drilled and tapped radially for the thread of the spindle. If that's worn, that's the best you'll get.


That's a good data point.  That is part 206, which is called a barrel nut.  Might be worth replacing then.  Only costs $2.25.  Yeah, worth replacing!  Might help.  I'll take it apart to see if there's anything else worn.  The small parts seem relatively inexpensive on Grizzly.


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## fitterman1 (Dec 4, 2021)

You're right, but the issues i found was,
1. Worn spindle thread.
2. Wear or too much slop between the barrel nut itself and the bore it sits in.
These amplify your backlash to create a cumulative error


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## WobblyHand (Dec 4, 2021)

RJSakowski said:


> I checked my compound  backlash and it is .005".  There are two components to the backlash.  The play in the thrust bearing and the fit of the lead screw. You can remove almost all the thrust bearing play but as far as I know, there is no adjustment for the compound nut.


For the compound, where are you considering the thrust bearing to be?  Can't identify it on the parts diagram.


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## WobblyHand (Dec 4, 2021)

fitterman1 said:


> You're right, but the issues i found was,
> 1. Worn spindle thread.
> 2. Wear or too much slop between the barrel nut itself and the bore it sits in.
> These amplify your backlash to create a cumulative error


By spindle thread, are you referring to the compound rest leadscrew?


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## RJSakowski (Dec 4, 2021)

"For the compound, where are you considering the thrust bearing to be?  Can't identify it on the parts diagram"

In this case, it is the lead screw mount itself, P.N. 224.


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## fitterman1 (Dec 4, 2021)

Yes


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## WobblyHand (Dec 4, 2021)

benmychree said:


> Compound rest backlash is really not an issue.


True.  For threading, one is just going in one direction.  Actually, I find the loose graduated dial to be far more of an annoyance.  I've lightly touched it dial by accident and it moves quite a bit.  It would be better if it took a bit more torque to move the dial.


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## WobblyHand (Dec 4, 2021)

RJSakowski said:


> "For the compound, where are you considering the thrust bearing to be?  Can't identify it on the parts diagram"
> 
> In this case, it is the lead screw mount itself, P.N. 224.


Thanks.  That makes sense.


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## WobblyHand (Dec 4, 2021)

fitterman1 said:


> Yes


I will check the leadscrew for wear when I remove it.  Your HM thread on your lathe was quite amazing.  You did a lot of work on it!  Is it possible to make the nut from acetyl in a similar style?


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## fitterman1 (Dec 4, 2021)

I can't see why not, i just used brass because I had it.


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## fitterman1 (Dec 4, 2021)

Take note that the barrel nut has to be a precision fit in its bore, a very nice tight sliding fit to minimise backlash.


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## WobblyHand (Dec 4, 2021)

fitterman1 said:


> Take note that the barrel nut has to be a precision fit in its bore, a very nice tight sliding fit to minimise backlash.


Yes, I understood that from your post #8 of this thread.  Acetyl could be pressed into the bore for a tight fit.  Have both brass and acetyl to try.  I'll buy the nut from Grizzly as well, since it isn't very expensive.


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## fitterman1 (Dec 4, 2021)

Roger, give it a go, what have you got to lose, except for backlash.


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## rabler (Dec 6, 2021)

Just a reminder,  the front plate on that compound was not satisfactory as shipped.  I think you have both plates(?), the original and the one I made to improve the leadscrew alignment.


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## WobblyHand (Dec 6, 2021)

rabler said:


> Just a reminder,  the front plate on that compound was not satisfactory as shipped.  I think you have both plates(?), the original and the one I made to improve the alignment.


Yes, I have them both.  Yours is installed on the lathe.  I just think the nut (or screw) may be worn, when I take it apart it will be obvious.  Neither is an expensive part.  OT was facing some foot pads on the lathe.  4" diameter 1/2" thick 1018.  Cut without any drama.


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## rabler (Dec 6, 2021)

WobblyHand said:


> Yes, I have them both.  Yours is installed on the lathe.  I just think the nut (or screw) may be worn, when I take it apart it will be obvious.  Neither is an expensive part.  OT was facing some foot pads on the lathe.  4" diameter 1/2" thick 1018.  Cut without any drama.


Yea, completely possible that the nut was worn as a result of the torque from a misaligned lead screw.  

Glad you're satisfied with the handling on the 1018.


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## Mitch Alsup (Dec 6, 2021)

My G4003G (now 4 years old) has about 0.009 of backlash.

There are two components (mentioned above) the leadscrew threaded member and the thrust bearing.
The thrust bearing can be set as close as about 0.000,3" without adding a lot of friction to the setup.
The threaded member can be set so there is just a hint of friction on the handle--but this results in about 0.010 of backlash.

In any event, if you are using the dials correctly (proper technique and monitoring movement with dial indicators) up to 0.100 of backlash is not going to harm the parts--it just makes you hate using the machine.

Proper technique with ~0.010 and BL is realistically not an issue (and I have no DRO on this machine either.)


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