4-jaw chuck screw removal
4-jaw chuck screw removal
Picked up a nice 8" 4-jaw chuck, which, while large for a 12" lathe, will do a particular job I have (just need to watch the stick-out on the jaws).
I want to pull it apart and clean it. I got the jaws out, but the forks that capture the screws don't have screws to hold them in. They may just be pressed in, but tapping on them with a punch (as hard as I dared, which is to say, not very) did not budge them.
Any suggestions?
Steve
I want to pull it apart and clean it. I got the jaws out, but the forks that capture the screws don't have screws to hold them in. They may just be pressed in, but tapping on them with a punch (as hard as I dared, which is to say, not very) did not budge them.
Any suggestions?
Steve
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- Location: Elmwood, Wisconsin
Re: 4-jaw chuck screw removal
I have a similar chuck. I had to whack some of the forks pretty hard to get them out.
Re: 4-jaw chuck screw removal
OK, I left it soaking in penetrant.John Hasler wrote: ↑Wed Apr 25, 2018 10:45 am I have a similar chuck. I had to whack some of the forks pretty hard to get them out.
Steve
Re: 4-jaw chuck screw removal
That's good to know, I stopped when those forks on my 4 jaw independent wouldn't budge with light tapping,John Hasler wrote: ↑Wed Apr 25, 2018 10:45 am I have a similar chuck. I had to whack some of the forks pretty hard to get them out.
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- Posts: 1852
- Joined: Tue Dec 06, 2016 4:05 pm
- Location: Elmwood, Wisconsin
Re: 4-jaw chuck screw removal
Well, I was lucky. The first one started moving with light tapping, so I knew there were no concealed taper pins or similar. When the others were reluctant I felt safe in whacking them.
Re: 4-jaw chuck screw removal
Sitting overnight with penetrant (50/50 acetone / ATF) appears to have done the trick.
Once they started moving, they slid out fairly easily.
Not sure how important to get them back in the same hole, but I number stamped each of the forks.
Now I just need to clean it and put it back together.
Steve
Once they started moving, they slid out fairly easily.
Not sure how important to get them back in the same hole, but I number stamped each of the forks.
Now I just need to clean it and put it back together.
Steve
Re: 4-jaw chuck screw removal
Better to play it safe with chuck disassembly and reassembly imo. With 3 jaw well made chucks it's important to even get the pinions into the same holes during reassembly to duplicate how the chuck was finish ground. An independant may not really matter but I'm no chuck expert.With an independant the main accuracy consideration is having the jaw tips ground exactly square to the chuck face and parallel to the lathes ways. Might be worth a light regrind on the jaws just to be sure of that? Don Baily at Suburban Tools did a great video about preloading the jaws on a 3 jaw before grinding and I think the same idea is needed even on an independant for truing the jaw tips. If the jaws aren't true the work can have zero runout at the chuck face and be wobbeling more than you'd like an inch away from that.
Re: 4-jaw chuck screw removal
Here's the chuck all cleaned up and installed on the lathe.
I'll be making clamps that have circular features by machining the face of the disk and then bandsawing it into segments.
Steve
Here it is holding the piece of steel I plan to be machining with it:
It's a bit big (8") for a 12" lathe, but it will be nice for large jobs such as this. I'll be making clamps that have circular features by machining the face of the disk and then bandsawing it into segments.
Steve
Re: 4-jaw chuck screw removal
Now that cleaned up very well. Nice job.
Re: 4-jaw chuck screw removal
Agreed, nicely done. Can I send my ATLAS 6" 4 jaw for a similar cleaning?
--earlgo
--earlgo
Before you do anything, you must do something else first. - Washington's principle.
Re: 4-jaw chuck screw removal
That sure sounds easy enough. Thanks for the instructions.
--earlgo
--earlgo
Before you do anything, you must do something else first. - Washington's principle.