Barry N. Turner wrote:

I went to the shop to turn a bowl. I had a dry 10" X 10" X 4" Honduras
Mahogany blank that I bought some time ago. I turned the outside shape
with
a 4" foot and a 2" tenon. I power sanded the exterior and reversed the
bowl
to hollow it. After hollowing, I intended to reverse the bowl again and
turn away the tenon, leaving a simple 4" concave foot.

I trued the rim and started to establish the wall thickness, using my new
Crown PM bowl gouge. All was going well. The bowl was hollowed about
halfway down when I got a king-sized catch and ripped the bowl from the
chuck, leaving the 3/8" X 2" tenon behind in the jaws.

The bowl is intact, except for a deep gouge in the rim, which can be
turned
away. I salvaged the tenon from the chuck jaws and carefully glued it
back
to the bottom of the bowl using medium-viscosity CA glue. I'm going to
leave it clamped overnight and try again.

Considering the ease with which I was able to rip the tenon from the bowl
made me wonder, is a 2" tenon adequate for turning a 10" diameter bowl? I
suspect that it may be on the small side. Thoughts?

It maybe. Your problem sounds like one my grandson and I ran into today.
We were turning an 11" bowl out of cedar with a recess to put an expansion
chuck in. The recess broke out after we had reversed the bowl and locked
the bowl on the expansion chuck. What we did was find center of of the
recess and remounted it between centers, but used the chuck on the
headstock. Turned a new recess a bit larger with a bit thicker sidewall.
Worked well.

Deb