On Wed, 13 Sep 2006 00:09:49 -0700, charlie b
wrote:

Having just recently blown through the top of a turned lidded vessel,
and having noted that a light shining into the inside while looking
from the outside makes it semi-obvious how thick or thin the walls
are. But you can't put a light inside while your working on the inside
- duh. And it's kind of a PITA to turn the lathe off, get the tool
rest out of the way, stick the light up against the opening of the
hollow form then look at the piece from the chuck side.

BUT - You Can get donut shaped fluorescent light bulbs. And if
you can fix it to the drive end of the lathe - behind the chuck
or around the chuck - and made some kind of shade - then
you might be able to use light to tell you how thick the wall
of the piece your working on is getting. Could probably turn
a "shade" even.

Brilliant idea or a dumb idea?

What you're describing, I think I'd pass on... but I do use light for
thin stuff. What I do is take a floor standing goosneck lamp with a
cone shaped shade that we decided didn't look very good in the house
and shine it directly into the hole used for hollowing. They sell
decorative bulbs at the store that have very thick glass and come in
high wattages that are great for the purpose.

And yes, I've used this for making lampshades. Easiest way I've found
was to hollow first, then shine the light in while turning away the
outside. It's by far the easiest way to insure a consistant level of
translucentity (if that's even a word...)

Careful of the wood selection, of course- wet wood turned that thin
cracks sometimes, and when there's that little material holding the
wall together, you don't need to cut through. The air whipping past a
hairline crack is sometimes enough to make the thing explode.
Exciting, but not exactly safe!