101 Lathe Quick change gear missing?

DmarionK

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New to the forum.
I have an craftsman 101.27440 lathe and I am wondering if I am missing a gear. It looks like the diagram only shows one gear, but I feel like something is missing. I have a gear that came with it that is destroyed, but it's the same as the one on there. Am I missing something or can someone point me in the right direction?
Thanks.
 

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Welcome to the forum. We will try to help you out. Because of the angle of your pictures it is hard to tell if you are missing a gear. You need to take a picture looking directly at the end of the lathe showing all of the gears. Something like this. This is my Craftsman 101.28910 showing the gears needed to cut metric threads through the QCGB.

IMG_3935.JPG
Your lathe should have a 32/16 tooth combo gear that drives a 40 tooth sliding gear that drives two 48 tooth idler gears that drive a 32 toot gear in the QCGB. The 40 tooth sliding gear is slid in the outer position to mesh with the 16 tooth combo gear for cutting 8 tpi threads and finer. It is slid into the inner position to mesh with 32 tooth combo gear for cutting threads coarser than 8 tpi.

In your pictures I can only make out the 48 tooth idler gears and the 32 tooth gears in the QCGB.
 
I think the gears on the side of the machine are good. I'm concerned about the gears in the gear box. One gear is floating and I think the smaller gear is suppoused to be facing out not in. The collar is on the outside unlike your machine, where I think the collar is inside. I tried circling the gear in question on my phone.
 

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I looked at my lathe and the manual for my lathe and the manual for your lathe. You are correct that the gear in red is should be reversed so that the small gear should be facing out. The collar on the outside of your gear box should be on the inside of the gear box between the gear and the end of the gear box. There should be a set screw in the collar.

chrome-extension://efaidnbmnnnibpcajpcglclefindmkaj/http://vintagemachinery.org/pubs/222/27468.pdf
 
So I flipped the gear around, and moved the collar to inside of the housing, but there is still a gap between the gear and the collar. It seems like the gears mesh and it feeds in all the gears. Is this just how the machine was designed, or is there supposed to be a collar/spacer between the gear and collar? Thanks for your help.
 

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I have a similar lathe (converted 101.07403) and I have the same gap in my QCGB. It works fine. It looks to me like the other gears keep each other in place.
 
I have an Atlas 3996 which was the last model that Clausing-Atlas built (at least of the 12"). The parts manuals are not clear on this point but the final part of the gears attached to the headstock rather than in the QCGB proper in mine consists of two 48T gears in parallel driving the wide gear in the QCGB proper. This would account for there being another 48T gear found with yours. Albeit in damaged condition. I would recommend acquiring the additional 48T replacement gear and installing it. You may also have to acquire additional keyed bushings (if they aren't floating around there, too) and discard one or two locally-made spacers that were addded in order to get by with only one 48T gear.
 
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