Thumper said: "After
all, hide glue becomes fairly gelatinous in all but
very low humidity, so this, combined with the glue
line stress in CC boards could lead to premature
failure, and increased compression-ridging.
But this may be much less of a problem with
modern glue types.
Right?"
Thump
Wrong! Obviously you haven't/don't work with much hide glue! Hide glue is
still the strongest glue in existence, when properly used/applied. It only
gets "...gelatanious..." in extremely high humidity situations, (read WET!).
I did an experiment with an olde upright cut-off bar, that was glued to the
sound board. Approximately 27" long by 2 1/2" wide by 1 1/4" thick. This
was/is attached to a chunk of soundboard approximately 2 square feet in area
with a thickness of 5/16". I had read/heard that Adolph's Meat Tenderizer
would break hide glue joints faster than anything else. So, I doused this
thing with a solution of Adolph's & water. Absolutely NOTHING HAPPENED! I
then immersed the whole thing in a bucket filled with the Adolph's solution.
Nothing again. To this day that cut-off bar is still firmly attached to it's
piece of sound board! Since the initial experiments I have done other things
to it, also. To no avail! Yes, hide glue takes some getting used to, but
it's THE GLUE for pianos, IMO. There are "acceptable" substitute glues,
which most rebuilders use for general wood to wood joints, that they NEVER
want to come apart. They use these glues because they are easier to use and
serve the same purpose. I have no problem with that. I will have to say, I
have about 20 different types of glues, adhesives, epoxies, etc., in my
shop. I use them were it is appropriate for the application. I'm sure most
serious rebuilders do much the same. The bad rap that some choose to give
hide glue is unwarranted, IMHO!
Regards,
Joe Garrett, RPT, (Oregon)
Captain, Tool Police
Squares Are I
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