For what it is worth in this discussion, my Fischer Ampico Grand was
rebuilt in 1987 by Gene Skarda in Minneapolis, Minnesota.  At the
time, he somehow blew shellac through the metal drawer tubing and on
the original pot metal elbows in the back of the system.  I do not know
how he did it but I do know that his pianos always played and
reproduced very well.

This rebuild is going on 23 years and it is frequently played.  The
piano still plays well and reproduces better than many new rebuilds
that I have heard.  My Fischer was the last one that he ever finished
before he passed away but this was one of his secrets.  I know that it
should not have worked but it has!

Randy Hammond