My blank was green but had been cut a while and was Anchor Sealed. I didn't
get the impression that warping was the problem, but I may have been wrong.
I'll try some of your other suggestions. Thanks.

Barry


"Mike" wrote in message
ink.net...
Barry,
Some other answers have alluded to green wood. Two comments.

Wood isn't always homogeneous, there might have been areas in the wood
that were denser (or lighter) than the rest, and when you removed enough
of the inside of the bowl the difference was enough to cause the
vibrations.

The other comment, an 11" bowl does take time to turn, and we all ( I do )
need to take some time out for a 'bio break', lunch, or just sharpening
the gouge. And I have a light close to the lathe. Make sure you turn
that light OFF when you don't have the piece turning for extended periods
of time (what ever that means). The heat from the light can dry one side
causing warping, or just enough drying to cause it to loose balance. For
long times (lunch) wrap the blank with a plastic bag. This will keep some
of the moisture in the wood but it may collect in the 'lower' side of the
blank.

mike



Barry N. Turner wrote:
I was hollowing a Sassafras bowl about 11" in diameter this afternoon.
The walls were about 1 1/4" thick and I was using my Crown PM 5/8" bowl
gouge with Ellsworth grind. Near the rim of the bowl, at the beginning
of the cut, I began to experience some vibration.

I put a fresh edge on the gouge and finished with little problem, but
still with some vibration. Then a thought entered my mind........had I
switched to a smaller gouge, say a 1/4" bowl gouge, which would remove
less wood per cut, would it lessen the amount of vibration? Thanks.