(Sorry if this is off topic. I couldn't really tell from the FAQ, and there was at least one other, unclosed repair question) I'm borrowing a Schilke trumpet (serial 55xx) and I'm having some trouble ...
I have a fifty year old F.E. Olds & Sons Ambassador cornet. It lay unused for 30+ years (it is now oiled and greased properly). There is considerable tarnish on the mouthpiece and on the slides. ...