Bernt Damm said he would use the metal rods behind the jacks to mute
the piano notes.  This is what I have done in the orchestrion I am
building.  It is easy and does work, but if I was doing another one
I would use pouch cutouts teed from the tracker (3 sets), and have
these switching either to the 24 piano notes or the other instruments
as required.  This overcomes any worries about loading the stack valves
with any extra pneumatics and pouches.

Mine runs one small pneumatic and a pouch (for the glock).  Tests I
have done seem to be satisfactory but too much spring tension on the
organ pallets will add load at lower stack playing levels.  I had a
difficult time getting the 24 tubes out of the piano stack and now I
am building a pouch interface for the glock anyway.  Would have been
easier to build 3 pouch sets and be done with it.

As far as when the instruments come on -- leave this up to the roll,
it controls them!  The roll controls the lock-and-cancel valves which
switch on the respective instrument supply cut-outs; when they are on
it plays.

My roll box has 'stub' axles each side; the flanges fit on a solid axle
through the roll and this goes into the box sort of like a normal roll,
except you have to assemble it (axle, flanges and roll) first before
putting into the box.  Yes, the flange has grub screws to hold it onto
the axle.  To make something like this without an axle would be, in my
opinion, too flimsy, and asking for problems.

Hey, its nice to see some orchestrion building discussions just at the
time mine is being made!

Peter Coggins
Blue Mtns.,  Australia