Author Topic: 3 jaw self centring chucks  (Read 3864 times)

Offline AndyB

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3 jaw self centring chucks
« on: September 17, 2011, 10:06:17 AM »
Hi all,

While going through my boxes of bits I have found 3 sets a external jaws for 3 jaw chucks.

They don't fit any of mine; how do I find out what they fit please? :bang:

They have got numbers on them:

29787 ( 1, 2 and 3 obviously)
28148
639

Does this mean anything in the grand scheme of things? Or am I just stuck with them until the day that I suddenly come across a chuck that fits? :doh:

Many thanks,

Andy
Waveney Valley, Suffolk/Norfolk Border

Offline BillTodd

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Re: 3 jaw self centring chucks
« Reply #1 on: September 17, 2011, 12:22:00 PM »
that'll be only a serial number :(

All I can suggest is to measure the spiral pitch, width, and slot dimensions hope someone recognises them.

I have a couple of unknown chuck bodies that could do with jaws (if only to use on a ro-tab)

Bill
Bill

Offline AndyB

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Re: 3 jaw self centring chucks
« Reply #2 on: September 17, 2011, 02:54:34 PM »
Thanks Bill,

I will put measurements up when I get a moment.

It seems a shame to not be able to identify them when there are so many chucks going cheap on eBay with only internal jaws.

Andy
Waveney Valley, Suffolk/Norfolk Border

Offline AndyB

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Re: 3 jaw self centring chucks
« Reply #3 on: September 18, 2011, 01:41:23 PM »
2 appear to be identical;

pitch is 1/4" or 4TPI
From the base of the thread to the top of the jaw is 1.457"/37.07mm (any discrepancies in the conversion are due to me just pressing the mm function on my caliper)
width of jaw .620"/15.75mm
width of chuck slide .402" (side to side)
height of chuck slide .313"/7.9mm (base to top)
front to back 2.02"

The other;

pitch is 5/16"
height from base of thread 1.1"
width of chuck slide .291"
height of chuck slide .193"
front to back .754"

Any ideas gratefully received

Andy
Waveney Valley, Suffolk/Norfolk Border