Holding a Square piece in a 3 jaw chuck

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liveaboard
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Re: Holding a Square piece in a 3 jaw chuck

Post by liveaboard »

10 years ago I needed to round and thread a bit of 30x30mm solid rod for a tractor part. I only had a 3-jaw chuck at the time.
I had a 20mm die, so I made it 20mm.
I didn't had a steady rest and the piece wouldn't fit through my spindle.

I bored a short length of 1" pipe to fit over the corners of the square, cut it lengthwise, and used it as a bushing. When clamped in the 3-jaw it held the square stock successfully.

I made a quick dirty steady rest that clamped to the bed, with a pipe in the center. 1-1/2" I think. a 1-1/4" was turned to fit into it, and the stock was held in that. I don't remember how exactly. Anyway, with some oil added from time to time, it worked ok for the job.

I cut the 30mm square down to 20mm round for a few inches in front of the chuck, and cut of the end when I was done.

The 2 braces I made that way are still in use.
Mr Ron
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Re: Holding a Square piece in a 3 jaw chuck

Post by Mr Ron »

Rips wrote: Thu Dec 02, 2004 9:54 pm These are all great ideas. Just a bit more information: the piece I am holding is a 1/8" square by 12" aluminum rod. I need to round one-half (6") and I need to make about 10 of them. I tried Patent's idea and it seemed to work fine. I have think if I had to do it again. I may try a set screw or GMAs soft solder fill method.

I am slowly learning the quirks of this hobby (the hard way!) and I do appreciate all the suggestions. The first lesson I learned was having way more patience then is humanly possible. If I rush something, if is plain dangerous and scary.

I'll have more questions soon. Thanks.
Since the piece is so small, I would recommend using a collet in a collet holder and a tailstock center. Take very light cuts.
Mr.Ron from South Mississippi
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NP317
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Re: Holding a Square piece in a 3 jaw chuck

Post by NP317 »

Or purchase round aluminum rod!
RussN
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Re: Holding a Square piece in a 3 jaw chuck

Post by whateg0 »

NP317 wrote: Wed Sep 08, 2021 11:43 am Or purchase round aluminum rod!
RussN
That just shifts the problem though doesn't it? Then you have to make a bigger round rod smaller and make half of it square. Doesn't seem very logical to me.
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NP317
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Re: Holding a Square piece in a 3 jaw chuck

Post by NP317 »

I thought I understood that a square piece was being turned round for half its length.
Language. Gotta love it.
RussN
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