In dismantling the Kranich & Bach (K&B) player action, I have
encountered an unusual adhesive that K&B used to glue together the
decks of their player stacks.

The pouchboards are attached to the deckboards with blotter paper
in between as a gasket thus allowing for them to be separated if
needed.  The assembled deckboards are connected together with spacer
blocks that have wind supply channels through them and these are also
attached together with the blotter paper gasket in between.

I have been trying to determine exactly what this adhesive is.  It
does not dissolve in water, alcohol, naphtha, mineral spirits or
lacquer thinner.  In it's dry state it is hard as a rock and is
almost impossible to scrape off.  It is amber in color and somewhat
translucent (so at first I thought it was burnt shellac, but it isn't).

I did discover, however, that it softens with a heat gun to the point
that it becomes rubbery and the bond starts to let go, allowing it to
be scraped off in rubbery layers.  It has to be quite hot for it to
begin to soften.

It must have been extremely hot to get it to liquefy as it was clearly
applied in a liquid state.  You can see in the attached photos how it
oozed out from under the paper gasket.  As it gets hot it gives off a
somewhat sweet smell.  It does not seem to penetrate into the wood but
bonds to the surface and when heated enough the bond lets go.  It also
sticks strongly to metal.

K&B also applied it as a surface coat over the outside of the primary
pouch board.  They also used it to seal around the nipples and that
edge of the pouchboard.

Has anyone else ever encountered this adhesive that I have just
described?  Was K&B the only player company to use it?  It must have
been some type of adhesive used in industry and commercial
processes at the time, well over 100 years ago.  Is there any type
of solvent that it will dissolve in?

Thanks,
Dave Krall
Hammond, Indiana

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