I've been lapping the faces between the column and cylinder of my oscillating steam engine. I rigged up a sort of crank drive in the lathe to make the lapping machine driven. So far, I've used fine grade automotive valve grinding paste, and this got the faces matched, but the surface was rough. I then left it running for a while with the faces wetted with Brasso, and the surface is smoother, but still rather rough.
What can I use as an in-between lapping compound to get smoother faces? A mate suggested Solvol Autosol metal polish - would that be suitable?
-- Wally