HELP removing South Bend 9A cross-slide

scritch

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I just got a "free" South Bend 9A. "Free" because it needs a tailstock, a toolpost, and some serious work in the quick-change gearbox. Luckily, my brother is a machinist and can make me new gears.

The problem is that I cannot get the cross-slide free. It's a non-taper-attachment model, so the lead-screw nut is made such that I can't just take the screw out of it and try to slide it out. So I have to unscrew it or slide it out by taking off the dial and bushing. Unfortunately, the lead-screw is solid stuck. Like it's welded!

I did manage to get the crank and dial off, and the cross-slide itself is loose on the saddle, but I haven't managed to get the bushing off of the cross-slide casting. It is very solid in there. I think that's where the lead-screw is stuck; maybe corroded in there.

Any suggestions on ways to loosen up the lead-screw in the bushing and cross-slide casting? I've been putting Liquid Wrench in it, so I'll see what happens tomorrow, and if that doesn't work, is a torch a good idea?
 
Welcome,
Torch is last resort, halfnuts disengaged, autofeed disengaged, hopefully your brother will figure it out.
 
Welcome,
Torch is last resort, halfnuts disengaged, autofeed disengaged, hopefully your brother will figure it out.

Saddle is separate from the apron. It's sitting all alone on my workbench with just the saddle, cross-slide, leadscrew, and bushing together. That bushing isn't a left-handed thread? Is there a tapered pin I haven't found?
 
Have you looked in downloads for a parts drawing , that may give you disassembly idea .
I don't have a SB 9 but there are many here that do , someone should chime in shortly.
 
The bushing in the saddle is right hand thread. The cross slide screw is left hand thread.

Take the screw out of the nut on top of the cross slide to separate the cross slide from the nut and screw.

With the handle and dial off, unscrew the bushing from the saddle.
 
My next approach will be to make a pin spanner for the bushing. Unfortunately, the lead-screw nut is the kind that pokes up into the saddle, so it won't come out until the lead-screw is removed. And since I can't turn the lead-screw, that's that. So, I'll make a pin spanner and reef on it until I get nervous, and then maybe get the torch out.

And I have drawings, but they simply show parts and numbers. Not good exploded diagrams with lines showing placement of the various parts.
 
Once you unscrew the bushing it will allow the nut to drop out of the cross slide and you can remove the cross slide and then the nut and screw together and the you can work on them.

DO NOT apply a torch to the saddle. The bushing will unscrew. If you must, use a small pipe wrench. If you booger up the bushing it is easy to make a new one. I have the original screw and nut and bushing and dial from my lathe if you need parts you can't find.
 
Here is a cad drawing I did on my 9" South Bend lathe over the years. See if it will help.

Ken
 

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  • Cross Section of Carriage Assy on a 9 Inch South Bend LAthe.pdf
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Mark, thanks for the admonition and encouragement. I went back, rethought the problem, and got it unscrewed without a pipe wrench. I actually used a small screw, a bit of copper sheet, and my big-ass Knipex gas pliers. I knew they were worth the money!

The very thin coating of surface rust on the screw shaft inside the bushing was enough to really lock it tight. I cleaned it up and now it runs very smoothly.
 
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