Two days ago an event occurred which suddenly transformed my interest in
mechanical music from academic to practical: I now have an unrestored Karn
expression piano groaning the living room floorboards.

I spent a full day cleaning and examining it, concentrating for now on the
non-player components.  The stack was a breeze to lift out (with a little
help!) and it all looks just peachy, aside from the minor fact that most
of the rubber tubing had rotted and was lying in small chunks on the stack
pneumatics themselves.  The stack is an Otto Higel Co. "Metalnola" type,
as shown in Reblitz, p. 127.  I'm puzzled by Reblitz' terse dismissal of
this action, as this one's metalwork is in impeccable condition.

So, two questions:

1) While I have traced out as much of a tubing diagram as is possible,
there are still a few parts which are unknown.  The surviving tubing
provides one more tube-end than there are connection points.  This implies
to me that either I've missed something somewhere, or else (more probably)
a tee connector has fallen off with the dead tubing.  I can probably
sleuth out this thing completely if I spend enough time on it, but just
in case, can anybody supply me with a tubing diagram, if only for a
sanity check?

2) Assuming that the Metalnola valves need rebuilding, has anybody a
recommendation for specific rebuilding parts?  Player Piano Co. part
numbers are welcome!

Thanks for putting up with endless newbie questions, folks.

Colin Hinz