The real answer already given - make edge detail early early while the bowl
is still close to circular - I'll explain a bit of why the bowl blows up or
runs off. As you look at a wooden bowl cut "normally" with the heart
toward the bottom, it's not circular, but oval. The longer grain portions
are less distance apart then the short grain. Nothing wrong with this,
except it's the worst condition to have to try and work the rim. Your tool,
unless carefully presented, will be going from a void into the uphill side
of the long grain. This is a recipe for a catch or, at the least, an ugly
spot of torn grain even when inside the bowl, so it's best to avoid having
to do this on thin rims which might shatter.

But, if you are working the rim, start your cut into the face, not the
slope, where your tool will have full support as it makes entry, and the
difference in diameter will become merely a difference in shaving width,
rather than an uphill tear, squirm and dismount. It also makes sense to
make it a cut at minimum radial pressure, to avoid distorting what you have
further, and possibly breaking it. I use the same entry cut when doing the
semi final cuts even below the rim, as it allows the gouge to sever the
fibers under inward compression rather than ripping them and creating
sanding problems.

If I were going to scrape, it'd have to be a _really_ light contact on a
_very_ narrow area, and I'd still start in full contact at the face and roll
to the inside.

"AHilton" wrote in message
...
I used to have the exact same thing happen to me except my bowls usually
exploded. Like Bill Rubenstein suggests, do your rim shaping early on in
your hollowing process before you start hollowing below the rim very much
at
all. That's made the most difference in my bowl rims. And, as others
have
already mentioned, a light scraping action works quite well here.