
The slides appear to be raw brass. I've cleaned the insides of the outer and the outsides of the inner with Hagerty https://www.thomann.de/gb/hagerty_coppe ... polish.htm Copper/Brass polish. They certainly are moving better, but I find that every time I get it moving, go away for a day, and come back then a wipe of the slide comes of with black tarnish.
Any suggestions/advice?
The slides are okay, but there is a small hole in one of the inners - it looks like a worn out or imperfect repair. It's not big enough to really affect the playing - not like a water key falling off for instance. My first stop will be the local instrument repair shop, but any other advice on maintaining an antique instrument like this would be very welcome!