Thanks for the help. I'm still not sure what caused the vibration, but was
able to finish the bowl with little trouble. Thanks to you and some others,
I have several theories to check out. The blank was sound. It was green, but
had been cut and anchor-sealed several months ago.

I don't believe mounting was the problem. I used a SuperNova with standard
2" jaws snugged up tight on a short tenon. I stopped a couple of times
during turning and tightened the chuck. I also stopped to put a fresh edge
on my gouge a couple of times, the last time just before the final cuts.

Right now, the theory that seems most likely is the one my friend
suggested..........taking the walls down an inch at a time. Thanks for the
advice.

Barry

"George" George@least wrote in message
...

"Barry N. Turner" wrote in message
. ..
Another friend of mine suggested that I take the bowl walls to final
thickness incrementally, say an inch at a time, rather than making one
sweeping cut from rim to bottom. I think that may work. I just didn't
expect to have vibration when the walls were well over an inch thick.

It's not the lathe. All four (4) feet are solidly on the floor. I don't
think it was the speed either, but it could have been. I tend to turn
slower than most people I know. The blank appears sound. I have some
doubts about the 1/4" bowl gouge too. I have one, but have never used
it.

On a rim that thick, at relatively slow speed, I'd inspect the mounting.
Applies to wobble both free and with a load. You wouldn't be the first
guy, especially on green wood, to have squeezed too hard and crushed some
fibers so the chuck's no longer firm. Especially if you're holding wet
sapwood. Shake the piece. If it moves, re mount.

If it's not moving on its own, but only under load, it's the presentation
of the edge or the pressure on the bevel. With a 1/4" flute, you don't
have to be cutting too deep to bury the upper, non-cutting part of the
profile, and that will cause you to rip and slide over end and side grain.
The pickup fuzz should be obvious on green wood if this is the case.

Last, you could be riding that bevel. That will still give you a
relatively fuzz-free cut, but you'll get out-of-round really rapidly due
to the difference between end and face grain. If the gouge wants to move
in and out, that's what you've got. Sometimes you can even see compressed
lighter areas against a wet background where you rubbed the heel of the
bevel too hard trying to make a quick curve.

Changing speed is often suggested, but it's really the same as those folks
who say if you drive your car faster down a washboard gravel road you
won't feel it as bad. You'll still beat the crap out of your car, of
course, and increase the impact force with the square of the velocity, not
to mention the loss of control as your shocks are no longer able to get
the wheels back to the road. Same on the lathe. I turn slow, too. No
problem, as long as you sharpen and present properly. You can carve with
only the gouge in motion, after all.

A 1/4" gouge is a great tool where the curvature is fast, or the access
narrow. Use it where you have to, though mine has almost no grind at the
ears, making it more suitable for the above uses.

One last shot in the dark, though this one should have been obvious at the
get-go. I once cut a blank from wood that had been on its side for a
while, ending up with all the water on one side of the blank. That was a
grin and bear it. Not to mention, I had another blank to cut just like
it, afterward....