# Quick change tool post for G4000 Grizzly lathe



## Frogdiver (Nov 18, 2020)

Has anyone put a quick change tool post on a G4000? If so what brand/size did you use?
A really don't want a piston type though


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## DAT510 (Nov 18, 2020)

Little Machine Shop is a good source for OXA sized QCTP''s









						Quick Change Tool Posts
					

Compare the many quick change tool posts for small lathes.




					littlemachineshop.com


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## Frogdiver (Nov 18, 2020)

*Little Machine Shop is a good source for OXA sized QCTP''s*


Does the fact that the OXA is .750" smaller than the compound make a difference? I know the AXA is a little bigger and wondered
which would be better.


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## DAT510 (Nov 18, 2020)

What matters is the lathe centerline distance to the top of the compound.  There is some cross over between OXA and AXA, but if the distance is too short and you happen to purchased an AXA, there's the possibility that you won't be able to lower the tool holder enough to get it in centerline with the lathe.  

An AXA will be more rigid if it fits, but on a mini lathe it might not be noticeable.  

Here's a Shars image on determining the measurement for choosing the correct QCTP Size.


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## C-Bag (Nov 18, 2020)

I have a 9x20, the same as the 4000 and it has and AXA, not OXA.


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## Frogdiver (Nov 18, 2020)

That schematic should help. Thank you everyone for the replies.


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## Bi11Hudson (Nov 19, 2020)

My small machine is a Grizzly G-1550. The only difference of note is the 1550 has imperial threads where the G-4000 has metric. The 1550 is from Taiwan, the 4000 is from mainland China. . . I use an "AXA" tool holder and have yet to have any difficulty getting center. Sorry, I don't have any measurements handy. But the AXA fits fine and tool holders are interchangable with a Craftsman 12" machine. 

.


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## Frogdiver (Nov 19, 2020)

Thank you very much, looks like its the one I am going to go with


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## hman (Nov 19, 2020)

I've owned two G4000s, and converted both to AXA QCTPs.  First off, you need an adapter sleeve for the fixed stud atop the compound slide.  Little Machine Shop sells one:








						Quick Change Tool Post Mount, AXA for 9x20 Lathes 3712
					

QCTP Accessories 3712 Makes AXA QCTP a bolt-on accessory for 9x20 lathes; Threads over standard tool post stud; This tool post mount is internally thr...




					littlemachineshop.com
				




I've used both piston type and wedge type QCTPs.  Both have worked well.  Shars, CDCO, LMS, etc. sell the sets, as well as additional tool holders.  I've not had trouble with any of them.  

Possible modifications:
1.  I noticed in at least one case that the stress of tightening the mounting nut tended to slightly bulge the center of the compound.  When that happened, and the QCTP was mainly supported near the center, it became a bit too easy to rotat under load.  I fixed this by chucking the QCTP in a 4-jaw and cutting away the central area about .010" deep.  This shifted the holding force to the periphery of the QCTP head and held it firmly against unwanted rotation.  PS - that's the LMS adapter stud on the compound.





2.  It seemed like the operating handle on the QCTP was not well located - always getting in the way of things.  So I drilled/tapped three more holes at 90º intervals (using my mill).  One of them turned out to be the best, so I left the handle there.


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## Frogdiver (Nov 20, 2020)

hman said:


> I've owned two G4000s, and converted both to AXA QCTPs.  First off, you need an adapter sleeve for the fixed stud atop the compound slide.  Little Machine Shop sells one:
> 
> 
> 
> ...


Thank you, that looks like a good fit. Tool height was easy enough?


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## hman (Nov 20, 2020)

Tool height was great for everything I tried (⅛" thru ½" square tools).  The cutoff (parting) tool holder wants a specific height blade (I forget what it was), and IIRC, the round tool holder was bored for ¾" and included a sleeve for ⅝".  A couple of people have posted about oversize tool holders that will take ⅝" (or ¾"?) square tools ... but I don't recall how easy it was for them to align the cutting edge with the centerline of the part.


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