Terry Smythe asks how to glue Ampico Valve blocks and pouches with
hot hide glue. If they are "sliding around on you" and making a mess
out of your pouch, then I'd suggest that your glue is WAY TOO THICK.
For pouches, use a very thin mixture.

   Also, when you're not used to hot gluing, you should size your pouch
boards before gluing them up to the valve block body. Don't use heavy,
thick  glue-- just moderate. Consistency description is a problem here.
If I say syrup, somebody thinks of karo, some of maple, and some of old
blackstrap molasses that have sat around for fifteen years.  But if you
can discern the difference, then adjust to "real maple syrup." Also the
quality of glue differs. The percentage of heavy proteins in the
different glues allow you to use thinner mixtures than with cheaper
glue. And if you forget to stir occassionally, in any pot, your best
glue gradually goes to the bottom and you are skimming off the light
gelatins, which are still ok for pouches, but not for wood joints, in
my opinion.

   Pouch setters can be made best and cheapest from rubber corks. See
my book, "Orchestrion Builder's Manual"  chapter on Pipe Chests to see
how that is done (pictures there, too). The correctly made pouch setter
is concave, not convex, and rubber, not metal (which will not conform
and will double-cross you, thinking it's down tight when it's not). I
also tell you how to make one.  15-20 minutes later, you will have a
perfect pouch setter.

   Another problem is when your pouches are made from too thick a grade
of leather, and you have sanded the valve blocks' joint edge away so
that there is no longer a depression for the leather to sit in. When
you don't have any clearance anymore, the pouch board is just skating
around on a tiny ring of leather. If that's the case, go ahead and glue
anyway (This time, use heavy glue), but after they're finished, you'll
have to go back through them and add more glue. don't try to do it all
at the same time.

   When I do valve blocks, I use a box of the very smallest rubber
bands I can buy. each block gets two or three at a time, around the top
and under the pouch board, then before I let it go, I get the block
flat on its face, sitting on glass. They dry that way, and are almost
always perfect, without any need to do any more. If it is an Ampico B
valve block, I first clear out the ball bleed hole with a pipe stem
cleaner before I snap the bands. The glue has to be thin enough not to
be setting up on me while I'm doing this.

   Heavy glue sets up quickly. Thin glue gives you more time. It's
almost impossible to get too thin a glue for pouches, but I suppose
somebody will do that and prove me wrong. Maple syrup consistency is
about right for good glue with valve blocks. The better the glue, the
thinner you can get it and still have all the strength with low
shrinkage. Color of crystals are no indication of good glue. The best
glues however are about the color of maple syrup as soon as they are
made. Technical gelatins are relatively weak, but usually strong enough
for our purposes.

   The worst thing somebody can do is to use carpenter glues (yellow
glues) or epoxies on Ampico valve blocks. Not only can they not get
them back apart, but the joint will "creep" and in a year or less, the
valve block will be useless and usually unfixable. All your bottled and
tubed glues are plastics, and plastics deform and stretch over time
under a constant tension. That is why they will never hold loose chair
rungs for long, or fix furniture joinery unless it's a lap joint and
screwed together. A good joint is, by itself tight, and the glue
prevents it from coming apart. There is only one kind of glue that both
makes a sloppy joint tight and also prevents it from coming apart, and
that's a glue that is not plastic and will not deform over time, and
which makes both a mechanical and a chemical joint with the wood.
That's hot hide glue (a good grade of, that is). A wood joint cannot be
flexible and hold for very long (contrary to popular opinion).
Therefore, a wood glue should not be flexible, either. That's why they
have never improved on animal hide glue.

Craig B.