bass strings

[Carl Teplitski]

Recently tuned a console model piano with very " buzzy bass " strings.
Looking it over,
I noticed that something like coke was obviously sprayed everywhere ,
including
the hammers, dampers, and strings.  Piano is in a church auditorium
setting where
young people gather to play basketball, lunch, and study. The buzz is
very metalic,
like the windings are loose.  Tried to twist a couple with no success.
Wondering if the coke may be the culpirt. Also wondering if there is a
way to clean same,
as the possibilty of replacing these strings is remote.  ( not all
strings buzz, but randomly ) ????
 I have heard of the possibility of sandblasting to clean , but don't
know.
Would it be hazardous to take the bass strings off without lowering the
tension on the rest of the piano?

Carl / Winnipeg