QCGB swap

ARC-170

Jeff L.
H-M Lifetime Diamond Member
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Oct 17, 2018
Messages
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I have found a lathe that appears to be the same age and size as mine with a QCGB. My question is: can I put the QCGB on my machine and put the non-QCGB parts on the other one? It looks to be pretty strait-forward, but I thought I would ask to make sure.

The lathe is bigger than my current one, other wise it appears to be the same. I don't want to put a bigger lathe on my workbench.

Here's my machine for reference:
DSC00407.JPG

DSC00408.JPG

DSC00409.JPG

Here's the other lathe:
QCGB 1.jpg

QCGB 2.jpg

QCGB 3.jpg
 
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Robert will have the answer for you. I think that it is a direct swap as long as the two lathes are the same model. They sure look to be identical
 
Looks like you'd need to swap the two end covers too, and IIRC, aren't the lead screws different length for QCGB. If the other lathe is a different bed that length could be a show stopper. Are you just buying it for the QCGB and going to sell the donor with the swapped parts?

Best,
Kelly
 
Somebody on the site did this recently. I think in the end they found it easier to put the good parts from their change gear lathe onto the donor QCGB lathe. As I recall the lead screw was the main issue. This was earlier this year, maybe in the spring from what I can remember. Might have been a Logan lathe, but pretty sure it was Atlas.
 
Looks like you'd need to swap the two end covers too, and IIRC, aren't the lead screws different length for QCGB. If the other lathe is a different bed that length could be a show stopper. Are you just buying it for the QCGB and going to sell the donor with the swapped parts?

Best,
Kelly

Yeah, I knew about the covers. AFAIK, the lead screws are the same for lathes with and without a QCGB. I couldn't find anything on the parts lists and diagrams I have that indicated a different lead screw.

I'm going to put the QCGB on my lathe and sell the other one. It's a decent machine, I just don't have room on my work bench for a longer lathe.
 
I bought the lathe. It was part of an estate sale. It came with: a follow rest, steady rest (might be aftermarket or for a different 12" lathe, though), a milling attachment, about 7 chucks, a bunch of faceplates, some sort of turret attachment, bits, and a bunch of other stuff I'll need some help identifying. I'll post pictures later when I get it unloaded.
I also got a turntable for my mill.
It has the motor set up to go forward and reverse. It ran really smooth when I tested it. The ways seem ok; they had lots of grime, but a quick measurement showed about 0.002" of wear. I'll re-check this as there was too much grime to get a good reading. I was mainly wanting to see if it was really worn.
I will post the pictures in another thread and maybe document the cleaning. I may document the QCGB swap in this thread if it would be of interest to anyone. Might be awhile before I can get to it, though. I have to set up a place to put all this stuff so I can go thru it and clean and inspect it.
 
Somebody on the site did this recently. I think in the end they found it easier to put the good parts from their change gear lathe onto the donor QCGB lathe. As I recall the lead screw was the main issue. This was earlier this year, maybe in the spring from what I can remember. Might have been a Logan lathe, but pretty sure it was Atlas.

I couldn't find anything in the parts lists and diagrams about there being different leadscrews, hence my question, but I find it hard to believe it wouldn't be "plug and play" since the QCGB was an add-on option.

I guess I'll find out!

EDIT: I tried searching for that thread and couldn't find it. Let me know if you find it.
 
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You will want to swap the two 48 teeth idler gears for a 52/44 combo gear. Then you can cut the most common metric threads through the gear box and imperial threads 8 tpi and finer. You lose the ability to cut the few threads coarser than 8 tpi.

You scored Jeff. Way to go.
 
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