In article ,
charlie b wrote:

3. When you’re turning parts down to pretty small
diameters, do you want to work at higher RPMS
or lower?
4. Is “best RPMs” a function of the type of wood?
I know that pine crushes rather than cuts when
using bench chisels while maple, cherry, walnut
and, my favorite, mahogany cut nice and clean.

Hello Rotationista,

I'll echo what Ruth said about relaxing. Catches happen - it's a part of
the risk of creating work in which the person is in complete,
unrestricted control of the cutting edge. People are fallible when
presenting a sharp edge to spinning wood. But if you're tense and stiff
the outcome could be injurious or at the least unsettling to your
confidence. A moderately light touch is all that's required.

Think about feeding a board across a jointer or into a table saw. Being
tense and pushing against the machine's ability to cut is bound to lead
to an "event" or an injury. When you push against the cut you'll be off
balance if something at the point of the cut changes - leading to a
potentially nasty situation.

A similar understanding is in order for woodturning. Allow the legs,
shoulders, arms and fingers to control the rate of cut as well as the
direction. (As Ellsworth recommends in one of his videos, let the large
muscles do the majority of the work and let the small muscles put in the
delicate work.) Take light cuts. No, lighter than that. Allow the edge
of the tool to do the work. If you do happen to present the edge
incorrectly and get a catch your balance won't be affected and the tool
isn't in a death grip which will worsen the catch. A moderately light
touch allows you to pull back more quickly and there's no body weight in
the cut that you've got to reverse direction and pull back.

My personal preference for lathe speed is either 1250 or 1800 rpm - and
85% of the time it's 1800. I turn a fair number of spindles and start
out there. The only time I turn more slowly is when I have an unbalanced
piece and the only times I turn faster is when polishing. I generally
turn my bowls at 1800 and the alabaster rock I've been trying out lately
goes at 1250.

After 4 years of turning a lot of wood, I still get catches. But they
haven't been disastrous for about 3.5 years now - they're usually just a
spiral gouge that screws up a bead on my last finessing pass. Ain't that
always the way?

--
Owen Lowe

Northwest Woodturners,
Cascade Woodturners,
Pacific Northwest Woodturning Guild
___
Safety Tip'o'th'week: Never grind aluminum and steel or iron on the same
machine or workstation - Thermite.
http://www.hanford.gov/lessons/sitell/ll01/2001-36.htm