Bruce,
They did use a dual grinder set up with, I think, 8 inch wheels, one a
fabric buffer and the other felt? It was about 12 years ago and the people
went on to LA to do AT&Ts surplus.
Mechanical polishing is common with plastics.
It was a quick and dirty process for them. They were refurbing slightly
yellowed desk sets cheaply, not sure what plastic it was.
I will see if I can chase them down. I sold them lots of telephone stuff in
the 90s.
--
Paxton Hoag
Astoria, OR
USA