I've heard that in 1927 Steinway started using nitrocellulose lacquer
(excess war materiel from WW1, by the way).  In my experience, that is
about correct.  Many pianos did indeed have a shellac finish on them
prior to 1930 (never afterwards), but I am confused about this issue
and cannot find much of any exact information on it.

Pianos from 1900 to the 1920s seem to have a very thick finish film.
Sometimes it degrades past the crazing stage to where large sections of
it fall away, leaving thick islands of finish dotting the case (while
keeping the color).  This is far too thick a film for shellac, as I've
used shellac before and one never has to apply so much finish in order
to achieve satisfactory and proper results.

The only other place I've seen this thick finish is on early automobiles
and on leather fenders for horse-drawn carriages.  Apparently, auto
manufacturers had large finishing halls employing many varnishers with
paintbrushes, brushing finishes on auto bodies.  (Spray equipment is
also a production by-product of WW1).  Fancy cars in the early part of
the 20th century often had two bodies: one was sent back to the factory
to be re-painted every year, while the fresh one was driven around.
(I heard/read this in regard to Hollywood stars and their fancy cars).

Henry Ziegler Steinway reminisced about walking upstairs to the top
floor of the factory with the finishing man who would walk around
slopping on another coat of "varnish" (varnish being the generic term,
prior to "finish" which was adopted when the change to nitrocellulose
"lacquer" occurred) on all of the piano cases, indicating that Steinway,
et al., employed a similar manufacturing process to automobiles -- both
before and after the introduction of nitrocellulose lacquer.  However,
this still does not explain why pianos (and cars?) have this thick film
finish from 1900-1927.

Is this merely a too-thick coating of shellac?  I still doubt it.  So,
I wonder if anyone has any information on _varnishes_ from the past.

In the modern definition, a varnish is a resin plus a carrier which
reacts to a hard, non-soluble film (and which peels off in sheets or
flakes), and as opposed to a nitro lacquer or shellac finish which do
re-dissolve.  In the past, linseed oil was used as a common finish.
I do not know if "naval stores" varnishes were pine resin dissolved in
turpentine, but I wonder if this was the 1900-1927 finish on autos and
pianos (and wooden warships).

In 1900, the logging mania went south to the pine lands stretching from
Georgia to Mississippi, and the forest was quickly logged off.  It
would make sense that a superabundance of pine resin and turpentine was
sold cheaper than shellac to impatient American industrialists, but I
have no proof of this.  Natural resins were replaced by petroleum-based
artificial resins at some point, and soybean oil replaced the previous
oil in varnishes.  (Was that oil linseed oil?  I'm confused about this.)

I tried to explore this topic a few years back, but finally gave up.
As for melting wax, it is always necessary to use a double boiler to
maintain a lower heat due to danger of explosion.  It's not recommended
to heat up turpentine or linseed oil due to danger of fire and explosion.

Mark Ritzenhein

 [ Many more MMD articles on this subject are indexed at
 [ http://www.mmdigest.com/Archives/KWIC/S/shellac.html  and
 [ http://www.mmdigest.com/Archives/KWIC/V/varnish.html 
 [ -- Editor (Robbie)