Have been thinking of making a doughnut chuck to help hold some of the bowls I turn. I have seen many good examples here on LJ,s. As I am pretty simple and did not want to spend a lot of time making a large disc and several rings. Thought of a way to use my flat jaw with homemade extension jaws for the back half of the doughnut chuck and just made one ring for now which will fit many of the size bowls which I need to do the bases on.
There is reasons to have the safety of afforded by the outer ring as with the bowl I am mounting has a thin lip which could crush if I cranked down to hard with the jaws. With this set up the jaws are just snugged and the doughnut holds it firm.
This assembly is held together with four pieces of all thread. Some pieces of a router mat keeps from scratching the bowl. I will now show you the back side of this contraption. I know it is ugly but remember it is homemade from a jaw set and extensions of road sign aluminum by very cheap guy.
Here is the bowl all mounted after being cut from the waste block
The assembly spins perfectly and is safe to spin at a little higher speed since it can not jump off if you should get a catch. You have complete access to the bottom for your finish work.
Here it is all nice and finish turned. I will only use this if the project can not be held safely with just the jumbo jaws tapered rubber pins. There is an earlier blog on the making of the jumbo jaw extensions.
Thanks for looking and hope this helps some of you all to hold your bowls better.
-- I,ve had amnesia for as long as I can remember. Vernon