Posted by jeff miller on October 13, 2002 at 07:46:14:
In Reply to: trouble with silver tuba posted by Mookie on October 10, 2002 at 19:27:41:
It's hard to say without seeing it, but it sounds like it could be one of three things:
1) red rod underneath the plating (acids in your saliva degrade the brass alloy)
2) the result of intense heat (I've had this happen when soldering work was done on a silver plated tuba) or
3) when the tuba was plated, some solder flux or other caustic material wasn't properly cleaned off of the instrument, causing the brass to corrode underneath the plating.
Of these 3 suggestions, I'd guess number 3 is the most likely, as red rot usually won't get past the leadpipe, and if you'd had work done on the thing, you probably would have put 2 and 2 together when you get the horn back all bumpy.
Mind you, I'm no repairman, so it could be due to something else.