Are we talking Cuckoo clock bellows or mechanical bird bellows?

In regard to Cuckoo clock bellows, I was faced with replacement of the
bellows in my fine old German cuckoo clock.  I recovered them in tan
pouch leather, and they have worked well sounding the hour and half hour
for over 20 years!  The last time I inspected them ( and also to clean
out the bird droppings) the bellows were still in excellent condition.

I am sure that bird bellows for mechanical singing birds must be smaller
and finer...so cannot comment on the material to replace them.

Many years ago, I was faced with replacing the bellows in a Swiss
mechanical singing man.  At that time, I used zephyr skin, and had no
trouble with it adhering.

Since that time, I have ordered some zephyr skin from a certain Kansas-
based supplier, but the owner told me not to depend upon it, and
suggested tan pouch leather for some Seeburg pouches I was replacing.
Perhaps a better choice.

As for nasty letters, one should *never* write them.  It gives you a
poor image that will remain with you indefinitely.   If you state your
problem rather than being nasty, you will find you get much further
ahead in the long run.

Bruce Clark