I'm not sure if I'm one of the experts but after working on
pneumatic systems for 40 years I've formed a few humble opinions.
Before I bring up the subject of pouches let me say that anything
and everything you do in restoring a pneumatic player effects the
end result either positively or negatively.

For example: You may think you are using great pneumatic cloth but if
it is a little too thick or if it isn't glued on properly, especially
on the hinge end, it will take more suction to close it.  In the case
of a foot pumper, that could mean a little more effort in pumping.

Now to pouches.  The ease in which the pouches inflate and deflate
is critical.  Thick or rigid pouch material necessitates greater demand
to operate, and of course, to the extreme, if the pouches are too rigid
they simply won't work.  (Some systems won't tolerate any thickness
or rigidity at all!)  So whatever you do to pouches you must keep that
in mind.

After having said all that, I will say that I do treat pouches.
As I mentioned last week, I have used PVC-E from time to time through
the years and I have had good luck with it.  To my knowledge _all_ of
the player systems I've used it on are still operating.  I'm sure my
customers would let me know if they weren't.

More so lately I've gotten into the habit of simply treating pouches
with a leather conditioner.  (Be careful when treating pouches with
anything liquid -- if it touches the glued "fringe" of the pouch,
don't operate the pouch until it dries.)

Ken Marts
Sheridan, Oregon