Clamping Small Parts in a Large 4 Jaw

[JMI]

There has got to be a better way.
I use a lathe that has a 4 jaw that will not clamp with all 4 jaws a part smaller than about 1/2". This requires that I hold it directly with 2 jaws and use some sort of "packing" in the other two. This can be a real pain to set-up and get square/rectangular parts centered.
As a alternative I made a small clamp for holding small parts and that then would be clamped in the 4 jaw but it does not work very well. Not well designed.
I think a small clamp is the way to go but I need a better design. Anyone know where I can buy one or idea how to make one?
TIA

Jim

 

[tel]

In that situation I usually just use packing slips of (say) 1/8" thickness held on to the workpiece with double sided tape.

 

[te_gui]

Depending on how big your 4 jaw is, you could perhaps chuck on a small 3 jaw chuck or a collet closer. This setup works especially well for turning lots of eccentric parts so you don’t have to indicate each one.

Brian

 

[JMI]

A collet is for cylindrical parts yes? I also need something to hold square/rectangular parts.
I'm thinking there must exist a small clamp for holding small parts that can then be held in a chuck. Not a "spider" for facing but something to center with.

Jim

 

[CrewCab]

A collet is for cylindrical parts yes?

I believe collet's are available for round, square and hex sections Jim

<quick edit> :


That's 5c collet's guys ................ Like these

CC

 

[tel]

You can also hold square stock in a round collet, as long as the collet size closely matches the corner to corner dimension of the square.

 

[Stan]

The overall best solution is to go shopping for a 3" or 4" four jaw chuck. Used four jaw chucks don't have the runout problem of well worn three jaw chucks.

 

[JMI]

I'm thinking this may work:

http://www.use-enco.com/CGI/INSRIT?PARTPG=INLMKD&PMPXNO=949804&PMAKA=505-2240

Also like the idea of the old small 4 jaw.

Jim