I think I'd band saw it to rough size first, then gently go at it on the
lathe to finish. You can put the part on a piece of wood while band
sawing so it doesn't scratch.

Assuming that Perspex is a clear plastic, like plexiglas, I'd use a
sharp tool and a very slow speed. The stuff heats up and becomes sticky.

Pete Stanaitis
--------------------

Andrew VK3BFA wrote:
I want to turn up a round perspex piece to fit in a circular hole in
the front panel of a radio I am building. I start with a piece of
perspex 4 inches square, and turn in down to the required fit.

Had one go at it today - interesting. Generates enormous amounts of
swarf - ok, can live with that. Started by using a pointed tool to cut
it to roughly the right diameter - when it broke right through the
piece, it went "whang" and threw a big chunk across the room.
Mmm....not good.

Whats the proper way of doing this without generating missiles of
plastic (or steel, come to think of it.) - what sort of cutting tool
should I be using, and what speed should the lathe be running at, ie
fast or slow (yes, very technical..) Any lubrication required - it was
cool to the touch.

Its got a quarter inch hole in the middle to allow the vernier drive
shaft to pass through to the tuning knob - I cut the head off a bolt
and used this to chuck it to the lathe. Its got a bit of wobble,
probably need to get a straighter bolt - was grabbed out of the junk
box.. Is there a better way of mounting the project?

Words of competence?

Andrew VK3BFA.