The key to using a power polisher is to use a variable speed sander/polisher. This is what auto detailers use. I polished my Parks f/g tube at a LOW SPEED. If you can polish a car with it you should be able to do the same on an unpainted fiberglass tube. Utube should have videos of techniques in using a power polisher. Look for f/g boat restorations.
Your mirror is #1363. Be sure to register it with PiSigma.
Show us pics from all angles of the focusser. Does it have any marks on it? What did Cave use before the Rukes focusser?
Edited by KentTolley, 18 December 2018 - 11:08 AM.