Moistened greetings from the Pacific Northwest!  Erik York asks about
patching the wind motor on his 1924 Stroud (Pianola) Aeolian upright
with cotton cloth and tacky glue.  Glad you asked, Erik, I hope this
will help save you from a great deal of frustration.

At first glance this wind motor looks like a set of three bellows
(especially in grand pianos) but is actually six bellows.  They are
hinged at the center, with leather, like a teeter-totter.  This is why
(among many other reasons) the suggested patch-job is probably wasting
time: if the hinges are leaking it won't matter how airtight the cloth
is, the motor is still not going to run efficiently and therefore
continue to bog down and the piano will still be hard to pump.

The interior hinge of leather is usually still good enough to function
as a hinge but not an airtight seal.  Slathering "Tacky" glue over
whatever cloth is there plus another layer of whatever cloth on top of
that will only stiffen everything up, compounding the existing problem.

But let's suppose one were to try and patch anyway.  Maybe an acceptable
_temporary_ repair for a singular component such as the Tempo governor
or equalizer -- something that could be accessible from all sides.  But
that's not possible to do with the type of motor discussed here.  There
is no way to reach around each section without disassembling the outer
two bellows from the center pair.  If you do this, the rubber O-rings
between the sections will rip the cloth you're trying to patch!  Simply
stated, it would be far easier to recover everything than it would to
apply any sort of patch.

I'm willing to bet no one except the person that sold you the patching
materials will disagree.  Don't oil anything either, in case that was
suggested.  I hope it isn't the same person that has quoted you
$3800.00 to rebuild the pneumatic stack.  Be careful, Erik, and good
luck.

Eric J. Shoemaker
Wet City, Washington