Bison Set Tru Chuck

[oldtiffie]

Of course, as a last (first?) resort you could always use "soft jaws" as they will be a lot easier than mounting/remounting and adjusting a Bison chuck - lot cheaper too.

https://www.google.com.au/?gws_rd=ssl#q=bison+chucks

https://www.google.com.au/?gws_rd=ssl#q=lathe+chuck+soft+jaws

[lakeside53]

Last resort? I do that too even on my set-tru chucks! But soft jaws aren't suitable for all work holding.

[oldtiffie]

They are as good as most.

6-Jaw chucks seem to presume that the part is quite round so as to grip evenly on all jaws - if not they will/may only grip on say 4 jaws - and they may be either all together or maybe spread about.

3-jaw chucks with soft jaws grip on a "tri-pod" manner and are more even to counter the "out of round" in the part to be held.

6-jaw chucks are sometimes used to grip "thin skinned" parts with minimum chance of crushing them - as would be the case if gripping an egg-shell.

There is a lot of bison-related stuff here.

https://www.google.com.au/?gws_rd=ssl#q=bison+6+jaw+chuck

[Ron of Va]

My Bison chuck has four adjusting screws that are not 90 degrees apart. The orange tape indicates the location of the screws.