"M.J." wrote in message
...
Barry,
I assume that right up to the point where you had the "catch" your
tenon was doing it's job. It was not a question of how big the tenon was
or whether you should have used a mortise. The "problem" was the "catch.
If you intend to continue having "catches" then I suggest you get bigger
jaws for turning 10 inch bowls. If not then I suggest you analyze exactly
what caused your catch and do everything you can to avoid presenting the
tool to the wood in that fashion again. Makes more sense than getting a
"Tim the Tool Man" set of jaws for a very small bowl. IMHO of
course......I could be wrong...... ;^)


Tried to avoid my oft-expressed opinion here, so as not to sound a Leif (LDD
anyone?), but here it goes again. The width of the shoulder that the jaws
ride against, and the proper registry against the shoulder are the most
important factors in holding the piece. That way it isn't just the tenon
length you have to lever against, but the shoulder, too. Since the
shoulder is perpendicular to the angle of a proper cut, and extends farther
from the point of rotation, it has the greatest mechanical advantage.

Weakness of destructive grips - non wedge types - is that they are as likely
as not to push the nose of the jaws out of register with the shoulder as
into. With a dovetail, the wedge draws tight up against the shoulder,
whether that is an innie or an outie.

Then there's the tailstock issue....