Atlas 4 Jaw Chuck Restore (M6-844B)

[mattthemuppet2]

Oh believe me, this was an idea learned through experience

 

[pontiac428]

Instructions: Spray liberally. Wipe off excess.

...step left

 

[benmychree]

if that has a built in spindle thread, not a backplate, then all you need to do is remove the jaws and knock out the screw retaining pins out the back with a brass drift (or screwdriver if you're careful). Clean, oil, reinstall and you should be good to go.

Those Atlas 4 jaw chucks do not have screw retaining pins, the chuck body is threaded in the slot and the screws sit in a recess in the backs of the jaws, you just back the screws all the way out to remove the jaws.

 

[mattthemuppet2]

cool, never seen that before. I think I've only ever had Buck 4 jaws on my two lathes (Atlas 618 and SB9)

 

[benmychree]

cool, never seen that before. I think I've only ever had Buck 4 jaws on my two lathes (Atlas 618 and SB9)

I have one like that but a few of the outer threads are stripped, it would not really effect most of the range of the chuck, I tried to sell it on EB but the customer returned it, I am willing to let it go fairly cheap if anyone is interested.

 

[Jake M]

This little 4 jaw chuck came with my Atlas 618 Lathe

I've got one just like it, maybe an inch bigger, that came with my South Bend lathe...

everything seems good and it works well but a few of the jaws are stiff, presumably from dried up grease.

That's a very good possibility. Based on my experience, (after disassembly), the first thing I would do is mount the chuck on the lathe (without the jaws or screws), and verify that it's flat(ish) and spins true(ish). Mine ended up having a "quadrant" out of place, and I havn't decided yet if it was dropped (no evidence of that), levered on inappropriately (no evidence of that), or somebody yarned on the chuck wrench with a four foot cheater bar until something gave out. Mine did come with a well made, but home made chuck wrench.... (Causation, correlation, or unrelated?) ... I dunno... But it doesn't take much misalignment to render the chuck jaws "sticky", no matter how clean and oiled. I say check it first not because it's the most likely, but because it's SO easy to check, and it'll drive you SO far out of your mind until you figure it out.....

I've never disassembled one of these so any advice, tips or tricks are appreciated as far as order of jaw removal, etc.

The biggest tip is to don't overthink it. Start with number one if you like, or maybe number two or three if you feel like a rebel. Run the jaw all the way out unitl the screw falls out from behind it, then you'll have a loose jaw and a loose screw in your hand to play with. Repeat that three more times, and it'll be apart. It's really that easy.

The screws are not married to any position, and the jaws are stamped. The jaws can go back in the current or the reversed position, depending on your work holding needs. They need not even all go the same way.

A toothbrush is a good place to start, or a bore brush, or anything "scrubby" that'll get in there with some cleaner/solvent/etc. The only thing you don't want to use is abrasives. If you can figure out a good way to get your electric drill adapted to the drive...... You can also douse with cleaner and run the jaws in and out at ludicrous speed, the tight fit and some solvent will shave some crud out of there.

I keep the general purpose ISO 48 oil on mine, but any lathe oil (or any "NOT engine oil") would probably be fine. Grease in small amounts might be fine too, but it's more work to clean out for routine maintenance, and more messy when reversing the jaws.

 

[JRT]

I've got one just like it, maybe an inch bigger, that came with my South Bend lathe...





That's a very good possibility. Based on my experience, (after disassembly), the first thing I would do is mount the chuck on the lathe (without the jaws or screws), and verify that it's flat(ish) and spins true(ish). Mine ended up having a "quadrant" out of place, and I havn't decided yet if it was dropped (no evidence of that), levered on inappropriately (no evidence of that), or somebody yarned on the chuck wrench with a four foot cheater bar until something gave out. Mine did come with a well made, but home made chuck wrench.... (Causation, correlation, or unrelated?) ... I dunno... But it doesn't take much misalignment to render the chuck jaws "sticky", no matter how clean and oiled. I say check it first not because it's the most likely, but because it's SO easy to check, and it'll drive you SO far out of your mind until you figure it out.....



The biggest tip is to don't overthink it. Start with number one if you like, or maybe number two or three if you feel like a rebel. Run the jaw all the way out unitl the screw falls out from behind it, then you'll have a loose jaw and a loose screw in your hand to play with. Repeat that three more times, and it'll be apart. It's really that easy.

The screws are not married to any position, and the jaws are stamped. The jaws can go back in the current or the reversed position, depending on your work holding needs. They need not even all go the same way.

A toothbrush is a good place to start, or a bore brush, or anything "scrubby" that'll get in there with some cleaner/solvent/etc. The only thing you don't want to use is abrasives. If you can figure out a good way to get your electric drill adapted to the drive...... You can also douse with cleaner and run the jaws in and out at ludicrous speed, the tight fit and some solvent will shave some crud out of there.

I keep the general purpose ISO 48 oil on mine, but any lathe oil (or any "NOT engine oil") would probably be fine. Grease in small amounts might be fine too, but it's more work to clean out for routine maintenance, and more messy when reversing the jaws.

I use DTE 26 (ISO 68), hope that is good enough.