I am re-facing the valves on a late Schulz player.  The original inside
valve facing is a medium thickness pouch leather, with the smooth side
out, in contact with the brass seat that it rests on.  Is there a
concern about using a chrome-tanned leather versus a vegetable-tanned
leather on this facing?  I am concerned about corrosion over the long
term.

Joel Cluskey - Cluskeys Piano Works
Pittsburgh, Pennsylvania