8520 Knee Bevel Gears

Ok.. Got my new gears in hand and started into tearing it down. I thought I could do it all from the bottom but can't get good purchase on the lead screw to loosen the nut on top of the gear.

So I took off the table and cross slide and lead screws to get a socket on top of the gear. This is what I see. It has been thoroughly peened. What is the best way to hold the OD of the leadscrew and use an impact or rachet to loosen the nut?

The knee is still on the mill. I'd really rather not take it off. I don't have a lot of that kind of help to get it all back on.

I thought of milling some grooves in wood blocks and clamp it that way, sort of like a rifle action in a vice. It's pretty smooth and I doubt my strap wrench will hold it.

Is there a trick?

Thanks
 

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wow, what kind of moron does that?
If I remember the gear is keyed, why would someone need to peen over the shaft like that?

I think you might need to grind the top of the shaft and nut using a die grinder.
Or maybe take a drill bit that would drill the top of the shaft out.. same size.. I would grind the tip so it stays in the center already drilled, and a very flat grind you don't want to take much of the shaft off, so you want it taken off quickly.

Or I might just turn the nut off and hope that the shaft does not twist.
Or hit it with a torch and turn the nut off.. losing the nut is not a big deal, hurting the shaft is. That peening is not a little peening, it is heavy and excessive.

That's what I would do... hopefully someone else has another idea.
Good luck
 
What about using a nut splitter to get the nut off? That will let you get the nut off then you can clean up the threads on the shaft with a thread file. You may need to grind the top of the gear teeth a bit to make room for the splitter, but you do have a new gear in hand. You will then need a new nut that is likely available at the hardware store, even if you have to cut the nut a bit thinner.
 
was wanting to leave the screw installed. I'm going to try and clamp it with all my clampy devices and see if my impact will just spin it off.

If I damage the end of the shaft, I guess I can turn the shoulder down a little, but then I'll have to disassemble it. maybe.
 
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With the nut splitter you can leave it assembled.
 
I took mine completely apart….knee and all but I can see why you would rather not. Since the gear is toast, can you get to it enough to grind a couple of flats on the gear sides for a wrench or any sort of clamp? If you can’t get to it with a grinder, the barrel type wood clamp on the shaft should get it off.
 
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Barrel clamp.. that's what it's called.. I'll throw one together and see what happens.. Need to get some things.
 
Get a small pneumatic 90 geared die grinder and small carbide cutter.

Carefully remove area where damaged.

Cut nut away from shaft.

Carbide will make it a short job.

Sent from my SM-G781V using Tapatalk
 
Zertsman said:
Barrel clamp.. that's what it's called.. I'll throw one together and see what happens.. Need to get some things.
Click to expand...
So one thing you may not have thought about, is tightening all the gib screws (not hard, you don't want to damage the gib) with the right pressure the knee won't move and you might be able to in effect lock the screw.

just be careful.
 
barrel clamp worked. Drilled an undersized hole in the wood, split it, clamped it on and held the lead screw quite well. Was able to back off that nut with a rachet easily enough. Chased it with a tap and reused it. That part is done. Found new issues, will create a new thread if I can't find solutions.
 
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