In response to Larry Mayo's overheating turbine:  I had much the same
problem when building my first built-up nickelodeon some years ago.

I solved the problem by making a pneumatic controlled device that
would bleed air into the vacuum supply.  If the air flow was high,
the air introduced would be low.  If the air flow was low, then the air
introduced would be high.  It provided a more or less constant flow of
air through the turbine at all times.  It worked much like the governor
works on a wind motor.

Al Pebworth
Pebworth's Player Piano Center
Home of "Yesterday's Music"
http://www.pebworths.com