I know that there have been discussions in the past about what tubing
is suitable for player pianos.  This note is intended to highlight the
sort of problems that can arise when the wrong type is used.

I have recently been commissioned to overhaul an upright Duo-Art with
Aeolian stack.  It was bought by its owner from a dealer in the South
of England in the 1980s, described as having been "fully restored".
Over the last five years the valve chest had progressively deteriorated
in its ability to hold suction.  There were also other faults which I
shall not detail here, but suffice to say they smacked of sloppy
workmanship.

Upon disassembly I discovered that all metal valve seats had become
contaminated with a build up of oily, greasy deposits.  The trackerbar
tubing was of the fish tank variety: transparent.  It had become so
discoloured so that it was almost orange in places.  It seems likely
that there has been a chemical reaction between the brass and copper
connections and the plastic tubing.

The result has been a significant accumulation of globules of black
material on the metal seats such that the valve facings were being held
up, thus allowing leakage.  There was also a great deal of loose
shellac pieces in the valve wells.

Following a full cleaning of all parts the action now performs
perfectly again.  And, of course, the tubing has been replaced with
silicone.

If you have a player with transparent plastic tubing -- be warned!

Roger Waring - The Pianola Workshop
Solihull, United Kingdom
http://www.pianola.co.uk/