I have just made a bigger jaw set for my oneway chuck. I used the flat jaws and attached a 1 “ thick plywood base cut into ~5..5 squares. Attached a ~10 inch ring of 12 segments glued in groups of 3 from 1 5/8 well aged yellow pine for the jaws. The Id to od of the wedge was ~ 2.5 inch but should have been closer to 3 inch. The length of each wedge (od) should be about 2 5/8”.
I carefully aligned the ring segment to the plywood square making sure that the sections were flush with the edge. Cut off the extra plywood outside the ring and then mounted each glued up section to one of flat jaws.
I then turned tracks 5/16 deep and 5/8 inch wide starting from the outside. Making step jaws.

Then range of rings clamped is the smallest ring is about 3 7/8 closed and the Max ring is about 10”


What this allowed me to do was to flatten the rings for some vases that I was making. I sanded flat one side of a ring using the disk sander and then used my jaws to do the top. What I also did with a ring is to turn the inside true and I also put a slight tapper on the top edge.
Pictures show attached to jaws, the jaws cut, holding a ring, the ring cone press, sample results.

I then could assembled this new ring using a cone to press to built up base and be perfectly centered over the previous glued up rings.WoodChuckBack.jpgWoodChuckFront.jpgWoodChuckWithRIng.jpgRingPressed.jpgGw-VaseFront-19.jpg