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wrote:

Hi all,

I'm new to turning (so that may be the problem here...). I've been
practicing on some mahogany I had around and have gotten fairly
successful. Well, I picked up a block of walnut and haven't been so
lucky with it. I'm trying to hollow out a shallow bowl and my
fingernail gouge quickly catches and throws the bowl off the lathe.
This is bad. I'd really appreciate some help here. Here's what I've
observed:

1. The stock is being held by a nova chuck expanded into a recess in
the bottom of the bowl. It's held pretty tightly.

2. My 1/2" fingernail gouge is brand new, sharpened with a tormek
jig. Sure seems sharp to me. I've never used it before, so technique
could easily be the problem.

3. The walnut is very dry.

4. If I use a scraper, I can be pretty successful with the hollowing.

5. If I use the gouge, it catches brutally and throws the bowl.

Any thoughts?

Many thanks,
Joe

Joe, you said you have been turning mahogany (you ought to hear how my
granddaughter pronounces it), I would assume your are turning bowls with
mahogany glue ups. If so, it is a matter of a very light touch on the
walnut with your BOWL gouge, not a spindle gouge with a fingernail grind on
it. That assumption being made:

Drill out the center of the bowl with a forstner bit (bigger the better) to
get rid of the bulk of the material to be removed. Then, very, very
lightly work from the center to the edge, cutting your thickness as you go.
What I mean is, don't try to work the entire sidewall of the bowl at once.
While you will probably have to come back and touch it up with a scraper or
your bowl gouge acting as one, you will always be cutting into the
thickness of the bowl and supported stock. (Make a cut from the center to
the outside, go back to the center and cut to the outside again, until you
have the inside to where you want it).

Where did you get the mahogany?

Deb