"Mark Fitzsimmons" wrote in message
oups.com...
I think everyone's missing the real problem here. I'm guessing that by
using a gouge with an ellsworth grind, you're using it much like a
scraper. When you do this, you put a force on the edge of the bowl that
is radial (outward). This complicates rounding because every time you
cut, you're distorting the shape of the bowl. The vibration won't go
away once it's round. It may even get worse because it's thinner and
flexes more.

You need to use a tool in a way that puts the force axial (parallel to
the axis) which will drastically reduce vibration near the edge of the
bowl.

2 ways to do that, off the top of my head:
1. Use a regular gouge with a different grind in a cutting mode .
2. Use a scraper with a sharp corner to get the cut started near the
edge and define the round circle. Do not push the tool in a radial
direction, align it so you're cutting on the top edge of the bowl,
cutting straight back toward the headstock, just as if your tool is a
drill and you're going to push the drill into the bowl to make a
perfectly round hole. Once you have a round rabbet half an inch or an
inch deep (o two inches deep) you can use a gouge in a cutting mode
(not the ellsworth grind in a scraping mode) to move deeper, rubbing
the bevel on the already cut surface.

I have a couple gouges with a straight grind on them which can be used
to do both cuts... the first cut I do with the very corner edge of the
grind as if it were a skew, with the tool parallel to the lathe axis.
Works like a charm. You get rounder circles and cleaner edges on the
bowl, especially if it's a natural edge.

Once it's round, you can use the ellsworth grind to clean up the
surface as long as you use a feather-light touch., but it may sometimes
chatter, and you'll need to clean it up with sandpaper.

I think you're mis-characterizing the ellsworth grind here. As with any
grind on any gouge (or any tool) you can scrape with the cutting edge, but
the ellsworth gouge is definitely used in a cutting mode (riding the bevel)
the majority of the time.

Jr.