I have fun going to festivals, thresher shows, etc., playing music from
the 1920s on my old player piano.  I always get into a discussion with
people on just how a player piano works.  I am thinking it would be fun
to construct a Plexiglas model with a small vacuum supply to show the
action of the tracker bar, piano roll, pouches, valves, pneumatic
action, etc., to aid in responding to the questions.

I'm just wondering if there is anything like this already on the market
or if fellow MMDers have ideas on the best way to construct such a
device.

Larry Schuette - The Player Piano Man
Raymond, Nebraska