[ Bob Taylor wrote in 121021 MMDigest:

> Leather valves are used in the majority of my collection, but
> I think my experience with these two pianos with sponge makes
> a strong statement.  The right stuff is okay.

I first heard of this sponge at an AMICA meeting over 40 years ago.
I'm glad to hear some of it has a long lifetime.

I tried sponge rubber from Player Piano Co. and it hardened and
leaked miserably within 15 years.  I had another piano, a Steinway "O"
pedal grand (1911) running on its original leather valves which tested
out as perfectly tight in 1990.  It's still running on them.

When I re-built subsequent Steinway Duo-Arts, I just couldn't use
sponge or other modern materials and feel my work was "restoration
quality".  Call me a throwback or an idiot, but that's just how it is
for me.  I tried the new stuff, and don't like it.

The leather I've been using for valves comes from Columbia Organ Supply
as grey packing leather.  I'm about out of it so will have to see if
they've kept their quality up to 1911 Aeolian Company standards.

Bruce Grimes