are feed gears supposed to rotate around the bushings

ARC-170

Jeff L.
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I was trying to set up my Atlas Craftsman 101.07403 lathe to use the carriage feed to machine a long piece of aluminum. It seems the gears I have (the 64/20 tooth and the 48/20 tooth gears used for a 0.005" feed) will not rotate when I snug them down (not real tight, just enough) on the bracket (L3-58M). I think the sleeves (9-73A) are stuck/seized. Are the gears supposed to rotate on these?

Image showing the wide end of the sleeves:
lathe feed gears (1).JPG

Image showing the other side:
lathe feed gears (2).JPG

If they are seized, what's the best way to get them off? Use a rod and hammer to gently tap them out carefully?
 
The bushing should stay stationary in the gear and spin on the shaft. If they go on but don't spin you have them too tight and the nut is binding them up.
 
The bushing should stay stationary in the gear and spin on the shaft. If they go on but don't spin you have them too tight and the nut is binding them up.

Let me clarify:
There is a bushing and a sleeve. The bushing (9-70A) fits in the gear and has little tabs to prevent rotation. The sleeve (9-73A) goes inside that and over the bolt that holds this assembly to the bracket. I don't think this whole assembly rotates on the threads of the bolt, I think the sleeve is supposed to rotate, but I'm not sure.
I tried un-tightening the bolts a little and it didn't work; there was too much slop and the gears didn't engage properly. Something is not right.
Hope that helps.
 
The 9-73A Sleeve should be locked to the 9-69A bolt by the nut and washer. The 9-70A double-keyed bushing should be free to spin on the 9-73A Sleeve with the nut tightened snugly. The two double-keyed gears are locked to the 9-70A Bushing by the two keys. If the parts have seen a lot of use, the two gears will wobble a little if you push and pull one side.

Note that all of the A-suffix parts are 1/8" longer or thicker than the "non-A" original parts. The 101.07403 should have only A-suffix parts.
 
So I should be able to tap out the sleeve (and bushing), right? It currently does not rotate at all.
 
Yes you should able to remove them. The sleeve should be slightly longer than the total thickness of the two gears, to allow the gears to rotate. Dirt and grime with no lube should be the issue, unless the gears are of the incorrect thickness. Early gears were 3/8” thick at the hub and the later gears 1/2” thick. This is not likely the problem if previous owners were diligent on what parts they purchased and what modifications are required to use later gears on earlier machines. There is a technical bulletin about the gears available online for future reference.
 
The drawing for converting A-suffix gears to non-A is in Downloads. However, in the present case, unless a PO accidentally bought some used non-A sleeves, that is probably unlikely to be the problem. First, it would be quite obvious as the early parts would be a full 1/8" shorter. And second, the non-A parts in this case went out of production probably in the 1940's. The change was made with the introduction of the 10F, 101.07362, 07382 and 07402.
 
The 9-73A Sleeve should be locked to the 9-69A bolt by the nut and washer. The 9-70A double-keyed bushing should be free to spin on the 9-73A Sleeve with the nut tightened snugly.

^^^Perfect description^^^

From the looks of the pictures it appears the sleeve is protruding the correct amount to prevent the nut and washer from binding the gear. I would suspect an accumulation of grime between the bushing and sleeve is causing the problem.
 
Agreed. The photo clearly shows that.
 
The hubs on both of these are 1/2" thick. The 48T gear is labelled 48A. the 64T is labelled 64, no A. I can cut them down.

I was looking for the referenced technical bulletins in Downloads and found drawings of the sleeve and bushing, but not anything on how to cut the gear hubs down. I also could not find the drawing for converting A-suffix gears to non-A in Downloads. Typing in "gears" and "A-suffix" didn't help. Let me know where they are. I'm guessing it's just a matter of chucking up a gear and facing off the hub?
 
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