"Barry N. Turner" wrote: (clip) Any ideas would be appreciated. Thanks.
^^^^^^^^^^^^^^^^^
All the ideas that have been offered seem valid. But no one has mentioned
speed. Have you tried raising or lowering the speed, in order to get away
from possible resonances?

Another comment, though. The wall thickness you have may be necessary after
the bowl is dry, to restore roundness. I think it would be better to bag it
and wait for slow drying to take place. As the bowl dries and distorts, it
will be inevitable that you will experience uneven cutting. If you do this
more than onece during the drying process, you will probably have the
problem each time, so why not just wait, and suffer only once?