william kossack wrote:
I normally reverse a bowl onto my cole jaws and turn the bottom removing
the tenon or anything else as I put the last finishing touches on the
underside.
This bowl is just slightly too big for the cole jaws I have but I have
others that are roughed out and drying that are coming down up soon.

I have made several sets of extension arms for my Nova Cole jaws. Each
set comprises 8 L-shaped wooden arms. The long side of each arm has two
holes to bolt to the cole jaws, and a block of wood is glued to the end
of each arm. The cole jaws are closed right up, and the inside edge of
the blocks are faced off so they run true and have a slight dovetail
grip. This approach is also useful for bowls that don't have a rim
suitable to grip. The first set I made was to hold these small bowls:
http://www.seafoamwoodturning.com/Shopping/BB_bowl.htm


Obviously you need sufficient swing on the lathe to spin this
helicopter-like contraption, and there are safety considerations with
this approach. Don't run it too fast. I have VS so I can start at 0rpm
and work up - I'm not sure I would recommend this on a non VS lathe. You
also need to be very aware of where the extensions are, and if you have
any doubts about the construction, especially the glue up, don't use it.

Another option is to build a donut chuck, but I assume you really wanted
to make use of what you already have.



--
Derek Andrews, woodturner

http://www.seafoamwoodturning.com
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