Arch,

I think you are on the right track with the hitch ball. Too bad you
aren't in the North Texas area; I enjoy "reinventing" things and this
sounds like an interesting project.

If the "Archoulen" chuck doesn't work out, you could use the components
to make a pneumatic device to hold your turnings while you enhance them
-- carve, burn, etc.

Slowly I turned...
Randy