"Gerald Ross" wrote in message
...
This probably never happens to most of you, but occasionally while finish
turning the inside of a bowl, I hit a snag--not a real catch, but enough
to disturb the bowl on the chuck. It is hard for me to get it set back
just right. I reseat the bowl as before, but there will be a wobble. I
have tried holding a pencil loosely to the edge to show where to tilt
back, and used the tool rest to try to do the same, but often this is
unsatisfactory as well.
SNIP

The work isn't usually circular, nor the rim perfectly perpendicular to the
axis of rotation after hollowing. The cross-grain bowl bulges a bit across
and above the center. I don't go back to re-true these things, because
they're only noticeable when turning, not static.

I use smooth dovetail holds, which find a best fit circular pretty easily,
and hold the piece securely against the nose of the jaws at the bottom of
the mortise. They're so easy to work with that I occasionally re-mount
pieces I'm not happy with for make-or-break retuning, or peel the finish off
with my gouge to get a sandable surface on pieces where I don't like it.

It's hold, not grip that I'm working with, and I have to be careful not to
allow sawdust inside the mortise when I reverse, but my pieces run true and
between centers until they're at their lightest. I then make sure the hold
is snug and true before I release the center support.

I use the tapered nose of the center into the pin chuck hole on every piece.
If you have one of those Morse taper mounts for a chuck, you can put it in
the tail and chuck up a tapered disk of appropriate size to help align your
piece while applying alignment pressure to the shoulder of the tenon or the
bottom of the mortise. I use similar to keep goblets running true on my
NOVA live center. Bolt it on to the tapered insert, and it helps keep
things stable while the stem is reduced.