# 9x20 Lathe - how do you separate the A gear stack?



## Teuler (Jan 24, 2021)

I have a Harbor Freight 9x20 lathe and want to change the set up on the A gear stack.  This is the first time that I've tried to do that.  The current A gear stack is a 28 T / 40 T on a keyed bushing shown on the left in the picture.  I want to remove the 28 T gear and replace it with a 30 T shown on the right.  The stack then goes on the shaft in the back and is held on with a collar with a set screw.  Obviously, I want to avoid damaging the existing parts.


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## benmychree (Jan 24, 2021)

What does the other side of the stack look like?  Usually change gears like that should slip off the keyed sleeve easily, if the sleeve goes through both gears you should be able to push it out of the gears, if it does not go through both gears you could try to slip a knife blade or sharp chisel/screwdriver between them.


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## markba633csi (Jan 24, 2021)

Usually you would find something that's just a bit smaller in diameter than the bushing (like a socket) and then tap it with a soft hammer or block of wood till it comes out. If it's really stuck you may have to use a press or vise
-Mark


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## Teuler (Jan 25, 2021)

Thank you.  I soaked it in WD-40 for awhile and then had to press it out - worked fine.


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## jdm23 (Jan 26, 2021)

Faced the same problem the first time I put hands on the gears of my new to me lathe. All the keyed bushings, gears holes and faces were left rough and it took a lot of effort to be separated or reassembled. Plus, the train was really noisy. Since the idea is that one should be able to replace gears just loosening the shaft, that must be corrected. I placed every gear in the chuck and cleaned with coarse emery cloth. The bushings where patently deburred and slightly filed were interference were visible against the light. That took a lot of time but in the end every bushing now properly fits every gear or spacer.

Then I was not happy about the endshake of the compounds, especially when shaft is fully tightened. I tried of correcting the height of the hard washer and now it runs acceptably, still I'm not completely happy with it.


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## savarin (Jan 26, 2021)

I find on my 9x20 the gears run very quiet if I use motorcycle spray spray lube. It is incredibly sticky.


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