Let us all understand that _hot hide glue_ is a super product in the
repair and restoration of the player piano.  I admit that I do not
usually work on anything but coin-operated player pianos.  I would
and do so deplore redoing the work that some well informed person has
previously done with other materials than hide glue.  RTV, silicone,
caulking -- you name it -- have all been used to destroy a perfectly
collectible instrument.

Please consider that we are supposed to be carrying on a tradition of
player piano technicians that now spans over a 100 year heritage.
Shellac is another excellent product.  The guys who made these player
pianos had other materials at hand they with which they could experiment.
It was the hot hide glue and shellac that they used.  There is still no
improvement in any product that can replace the hide glue and shellac.

I am currently working on a beautiful and really pristine clean Seeburg
K.  The bellows cloth is less than ten years old and is hard as a rock.
The valves were replaced with sponge rubber and they leak, the leather
nuts corroded any metal they were in contact with, but it was done with
hot hide glue so I can restore this one without having to put in a lot
of time and new wood.  The striker cloth is still usable.

If you can't learn how to use hot hide glue and shellac then you will
never be a good player piano technician.

Don Teach