I built a machine, in the '80's to make CD's. In that machine, the CD blank was spun slowly while a plastic coating was
applied. The disk was then spun up @ about 6K RPM and back down in a second or two. The plastic material was slung across
the face of the disk and smoothed the surface out. It was called a "dust defocusing layer" and was to move any dust of
finger prints "up" out of the focus of the reading laser.
All the kits do is polish the surface of this coating until it's gone. The whole point is to fill any gouges or scratches
with a clear material so that the laser can read through the layer. A clear car wax or something like Future polish will do
wonder with a scratched CD as long as the scratch isn't to deep.
If you insist on using a lathe, mount the disk using the center hole, put some liquid polish around the center and start and
stop the lathe. But mind you, the lathe needs to be sitting on end so the disk is deed level.
R. Wink

On Fri, 19 Nov 2004 02:27:05 -0800, Derek wrote:

Not quite off topic, but .....

Has anyone here managed to remove scratches from CDs' (compact disks)
in a lathe?

I have a few that have been abused to the point that I can't copy them
and start over. I have tried various buffing proceedures with little
success. Any thoughts on the feasability of making a backing plate and
taking a light pass or two over the surface.

I'm a novice, so advice on chuck speed and tool shape would be
appreciated.

Thanks in advance.