Help taking apart Cushman 3 jaw chuck

[brandon428]

When using my SouthBend 9a the other day, the jaws locked up to where I could no longer close them. The chuck is a Cushman (ref #3005) solid 3 jaw chuck, which I believe to be the original chuck that came with the lathe new.

I started taking it apart: removing the jaws, taking off the allen screws, getting the back panel off, removing the inside allen screws inside, but now I'm stuck. It looks like the plate must come up, but I'm not having a lot of luck. There's a black plunger -- not sure what that is next to one of the allen slots and a small slotted screw on the outside edge.

I tried putting in 1/4" bolts where the allens went that were longer and had the bolt head above the surface. I tapped on them with a hammer which did seem to loosen up the jaws, but I can't get the plate to budge.

Any advice on how to get the rest of this apart would be greatly appreciated.

 

[Jim F]

Is that screw holding the pinion by chance ?

 

[mikey]

Take a piece of wood that will fit into the slot and go around to each slot and tap on the scroll. It will come out. Make sure you support the rim of the chuck and leave enough room for the scroll to fall out.

 

[Jim F]

Take a piece of wood that will fit into the slot and go around to each slot and tap on the scroll. It will come out. Make sure you support the rim of the chuck and leave enough room for the scroll to fall out.

I am not sure he has the pinion out yet.

 

[mikey]

One would hope he knows it has to come out first.

 

[brandon428]

Take a piece of wood that will fit into the slot and go around to each slot and tap on the scroll. It will come out. Make sure you support the rim of the chuck and leave enough room for the scroll to fall out.

I'll try that.

I am not sure he has the pinion out yet.

I can try the screw. Can't imagine taking it out could hurt if it's not, though I made the assumption that couldn't be holding the back on.

 

[brandon428]

One would hope he knows it has to come out first.

I was concerned it might be that black plunger -- which looks (but doesn't feel) removable.

 

[Jim F]

I'll try that.



I can try the screw. Can't imagine taking it out could hurt if it's not, though I made the assumption that couldn't be holding the back on.

The pinion has a pilot into the center hub. It has to come out before the chuck comes apart.

 

[mikey]

Brandon, the pinion is that gear looking thing your chuck key fits into to tighten or loosen the chuck. It must come out before you can remove the scroll.

 

[brandon428]

The screw did hold the pinion, took out the pinion and the wood trick worked. All apart now.

Suggestions on lube/grease after I clean?