Craftsman 3 Jaw Chuck Problem....

Incorrect position of the chuck jaws wouldn't cause binding. The jaws just wouldn't center properly. I suspect some chips have gotten into the scroll and are causing the binding. The solution posted by Chips&More should clear the problem.
 
A photo of the tooth side of any one or all three of the jaws would reveal the answer. But unless the Cushman is one of the very very few solid jaw 3-jaw chucks ever made, you cannot reverse the jaws. The exception would be jaws where the tooth shape is oval instead of the normal arc shape. Almost all 3-jaw scroll type chucks with solid one-piece jaws originally come with two sets of three jaws. They look almost the same except that the teeth are reversed relative to the steps.

If you pull the jaws out and look down through the slot at the scroll, what you will see are a row of curved teeth. The curvature of the teeth on the jaw must match the curvature of the teeth on the scroll.

This all assumes, of course, that you have a normal chuck.
 
Olddaddy said:
I've had my 12" Craftsman for a few months now and have regularly switched the jaws around from inside to outside positions. I've cleaned it and oiled it and all was well until last weekend. I took the jaws out to turn them and when I re-installed them the would not turn in and tighten at all. There are some broken spots on the teeth, but they have always worked before. I cleaned, checked carefully, oil and tried repeatedly to no avail. They are in the correct 1,2,3 positions. The Chuck is marked The Cushman Chuck Company, Hartford, CT. USA and it 5" in diameter. Can I replace the jaws? Should I look for another Chuck? If so, what do you guys recommend? And I have no idea why the pic is upside down......

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I did not know there were any scroll chucks that permitted the jaws be reversed. The curved "threads" on the inside of the jaws will fit the scroll only one way. Typically you need two sets of jaws, one for inside work and one for outside work.
 
I can't recall who made it or when but somewhere within the past two or three years I saw a photo of the teeth on the inner part of the jaws. Probably worked about as well as the traditional versions so long as you never chucked on the ID of a part. Given the increased cost of making the teeth, I can't imagine that the manufacturer saved any money by not having to supply two sets of teeth.
 
Here are a couple of pics. I think the jaws are not meant to reverse, which makes it all the stranger as I have reversed them.....really. Looking at them tonight they appear to be an arc thread as mentioned here and not reversible. I feel like I am entering the Twilight Zone!

image.jpeg image.jpeg
 
You are correct that the jaws are not reversible. Reversing them is most likely what caused the damage. You may have considerable damage to the scroll as well as bit of broken teeth.
 
I got that same chuck with my 12" Craftsman and it came with 2 sets of jaws.
One set for inside and one set for outside.
 
roadie33 said:
I got that same chuck with my 12" Craftsman and it came with 2 sets of jaws.
One set for inside and one set for outside.
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Well Olddaddy, I think you'd better start looking through all your drawers and cabinets for that other set of jaws so you can get yourself out of the "Twilight Zone" :)
I think Mike R. has your answer.

Ted
 
Any chance you crashed the chuck? Mine did the same thing...after I ran a 1/4" bit to close and stalled the headstock via chuck jaw to toolbit contact!:mad:
 
Well, I see why the wouldn't reverse, but they did.....unless I imagined it. The teeth were broken when I got the lathe. I took both chucks apart before using them and cleaned and lubricated them. I have looked very carefully and do not see other jaws in any of the bits and pieces boxes. I like the Chuck and would buy more jaws if I knew what to look for. There are no part numbers or anything on the Chuck or the jaws. Would I be able to buy by dimension?
 
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