How to remove South Bend 9 stud gear nut?

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ericc

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Hi. I bought a South Bend 9 lathe recently. It was missing some parts, but I'm slowly getting it working. In order to do some threading, I need to swap the stud gear on the reversing lever. This requires removing a nut. The nut is stuck. First, I tried to engage the gears and hold the chuck. It would not come loose. Of course, excessive torque was not applied, due to the risk of harming the gear teeth. The lever was removed, and it appears that there is no way to immobilize the other end of the shaft, since it is completely round. Again, holding the gears while attempting to remove the nut risks damaging the gears. I cannot understand what the engineers were thinking when they designed this. PB blaster first, then penetrating oil were tried. They didn't work. A torch was tried. It didn't work. What next? Is there a special trick to get this nut off? I can think of two ideas. First, carefully file two flats on the thin protrusion on the other side of the stud bushing. A wrench could then be used to immobilize it. Alternatively, a thin nut could be welded to the protrusion. I am more inclined to try the first, since it is less of a hack, but was hoping some restoration experts might know a better way. Thanks!
 
A picture would help me better understand the situation.

Kroil by Kano Labs does work better than many other rust penetrants. You need to order online though, not sold in local stores. You can order from Kano Labs site, Amazon or others.
 
Sounds like someone over tighten the thin jam nut and stripped the thread. It only has about 1-1/2 threads of engagement on the stud. It is right handed. Wedge a piece of wood into the gear teeth and attempt to remove.
 
Here is a photo.

This nut seems to have more engagement than a thread or two. The wood sounds like a good idea. I was just afraid of breaking the gear.

IMG_20180211_125934.jpg
 
I second the wood idea, I've done that too. Alternatively, you can stuff a piece of rag in.
Liquid wrench usually helps- or ATF and acetone mix.
Mark
 
Is it possibly a left hand thread? If it turns the same direction as the spindle, it would make sense to have it left handed so it did not accidently thread itself off while running.
 
Hi. No, it is right hand threaded. That makes sense, since it is a reversing lever, and it would be expected to go either direction. I was able to get it off by feeding a sacrificial wood wedge between the gears. It was really on tight. It was a little scary. I've broken a lot of stuff.

thank you for the timely assistance!
 
ericc said:
Hi. No, it is right hand threaded. That makes sense, since it is a reversing lever, and it would be expected to go either direction. I was able to get it off by feeding a sacrificial wood wedge between the gears. It was really on tight. It was a little scary. I've broken a lot of stuff.

thank you for the timely assistance!
Click to expand...
I too have broken stuff; sh-t happens!
 
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