Now that Craig and others have made hide glue a hot topic again,
let me add something cold to this sticky subject: Franklin's Titebond
liquid hide glue.
It looks and smells like hot glue, but comes in a squeeze bottle just
like Elmer's white glue or PVC. It obviously doesn't have the quick
gel and setup of the hot stuff, nor that handy property of penetrating
only part way through a layer of felt or leather. The formula includes
ammonium rhodanate and dicyanodiamide.
But I need to report my own experiment with it. I used Titebond to
repair a 1963 Autoharp whose bottom front hitch pin block had pulled
loose from the bottom plate and was twisting up and warping the upper
soundboard plate. The glued area would be about one inch deep by eight
inches wide, and must resist the tension of 36 metal strings, in pure
shear mode.
Several weeks after restringing and tuning the Autoharp, I can report
that there is absolutely no creep or other plastic effects, even though
the exposed glue outside the joint (I could have cleaned up better)
does not feel hard to the touch (unlike white glue). Yes, I did attack
the job with six clamps and left them on for two weeks, although three
days probably would have done it.
The label on the bottle recommends "It is ideal for musical instru-
ments", by which I assume they mean violins, guitars, dulcimers, and
Autoharps! The label also warns against using it "where moisture is
likely."
I'll let Craig speculate as to how easy this glue will be to break
apart and sand off by the next player piano rebuilder in 20 to 40
years. Also as to its gap-filling ability, though it seems pretty good
to me. I also recall that this cold hide glue was basically the hot
stuff with additives to keep it liquid.
It should not be confused with fish glue or mucilage. When Craig went
through most of this for us last year, I believe he mentioned that fish
glue would definitely creep.
By the way, any owner of a clavichord knows that wood itself creeps
(warps) under heavy loading after many years. So maybe we need only
that a glue should creep no more than the wood (tongue just partly in
cheek here).
Mike Knudsen
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