On Thu, 27 Oct 2005 20:23:48 GMT, Jim Flanagan
wrote:

Hello..
I wanted to ask anyone if they have attempted to do this on their
lathe. I only have a metal lathe and want to cut a flat archimedes
spiral onto a 1/8" thick piece of lucite. The spiral, fairly coarse,
would be something on the order of 6 turns/inch. The diameter of the
plastic would be about 3.5".

In any case, I could use some pointers as to how and efficently
accomplish this. Thanks for any advice you may offer.

-jim



is this the spiral made up of semi circles with increasing radii? If
so you can't do it on a lathe. You should be able to cut a "true"
spiral taking a facing cut at a "heavy" feedrate like .170" per
revolution *if* your lathe will do it. Of course there are details to
work out.
Randy