Compromise gluing

Julian Brook said:

> If a novice can try to reconcile a couple of opinions here, I think
> that everyone is correct.  The older guys involved in manufacturing
> and production didn't care for hot glue because it was not great to
> work with. They were not concerned with restoration.  The restorers
> like it because it makes it easier to take things apart to restore.
> So they are both right, it just depends on where you are coming from.

I would like correct this perspective.  Those who say that any of the
glues are fine, it just depends on how you look at it, are putting a
wrong slant on the subject.  The MMD Archives contain a lot of good
information about hot hide glue and cold hide glue, too (which can be
homemade, or which can be purchased).  There is no substitute for hide
glue, regardless "Where you are coming from."

I do, on rare occasion, use Titebond.  Titebond is a carpenter's glue.
So when I am doing certain kinds of carpentry where screws or clamps
and quick dabs are needed to stabilize a joint, I may use it for its
convenience.  I also use epoxies and silicone caulk, and I have
already mentioned that I use the super glues, too.  But when you check,
you will find that I and other rebuilders who use these other glues use
them for the jobs they were intended.

For example, Titebond is not a good glue by itself in any kind of
stressed joint like a chair or joints under continual tension.  It is
a plastic, and it slowly creeps, so it will finally bust.  You should
not use Titebond, or white carpenter glues, or any plastic-like glue
where the glue joint alone is responsible for holding parts together
under shear without other supports.  I know this is new information
to a lot of cabinetmakers, but a fact nevertheless.

The purpose of hot hide is not simply to make restorations easier to
take apart!  I wish to clarify this both for Robbie and Julian Brook
and others that we do not use hot hide glue solely because it is the
original glue and authentic, and makes disassembly possible.  That is
only one of the reasons.  Instead of reiterating all of the reasons why
we use hot hide glue, and to prevent someone from believing that our
comments are strictly altruistic from the "purists" point of view
(which they decidedly are not), I would point the interested reader
into the Archives where this information has been placed.

I have never advocated "compromise gluing."  There are many things one
has to glue and it is not wise to say that hot hide glue serves all of
these purposes equally well.  But if you want to learn why hot hide is
superior in rebuilding pianos and players, read what has been written.

That being said, hot hide glue can either be used by itself or as
the glue base for additives like aluminum sulphate (alum), potassium
chloride, urea, glycerin, acetic acid, potash, linseed oil, potassium
chromate, and many others which are able to greatly change the
characteristics of the glue to stick to things it would not normally
adhere to, or to prevent rapid set-up time, or to waterproof it --
like the old shipbuilders did.

One last (new) recommendation I want to make is that Franklin's Liquid
Hide Glue (which does not contain urea) I have discovered, is good glue
and very strong.  It may also be diluted with water up to 10% and not
lose its properties.  Any more dilution than that should be tried,
first.  I recommend it for all indoor applications when a slow setup
time and weighting or clamping is required.  It can also be dissolved
or melted by heat to remove, but becomes properly brittle-hard and will
never creep.  That means, you cannot glue pneumatics or anything that
requires quick setting, but it is excellent for tight woodworking
joints, butt joints like piano lids, and for some veneering jobs.

Craig Brougher