Hey folks,

Here is what I have found. About a year ago a friend of mine and I --
both longtime engineers -- made a test. We both had our opinions. He
liked Gorilla glue, I liked good old yellow PVA woodworker's glue.

We set up identical tests and tested the strength. We both found that
they both had, if properly applied, nearly the same strength. We
found that the PVA was slightly stronger in our tests. And the
strength variations due to application were greater with the Gorilla
Glue. The difference was not enough to be statistically significant.
The conclusion I have come to is:

PVA is the best for normal woodworking projects that do not need
waterproof service. PVA is more forgiving in application (there is no
special surface wetting and other concerns). Polyurethane (Gorilla
Glue) can be used to attach materials that PVA cannot (metal, plastic,
mirrors, etc). Polyurethane is better than even the type II PVA for
wet applications. Gorilla Glue does not fill gaps (with any
strength). Gorilla Glue is very, very messy and you absolutely need
gloves or you will be wearing the stuff for days on your hands until
the skin it is on wears off. Like most adhesives, they each have
their place, but I think the PVA is much easier to work with and
forgiving as long as you are working within its service parameters.

Eric

"John McGaw" wrote in message ...
"Gfretwell" wrote in message
...
OK I tried this stuff again. I was using hard maple, I wet it down good. I
glued both sides and seated a 1x2 into a 1/4" rabit that was a "tap in"
tight
fit. This was clamped overnight. The next day a light tap with a hammer
broke
the joint with absolutely no damage to the wood. I think library paste
would
have done a better job. Where did I go wrong? I can send pictures of the
bad
joint.

Your problem is probably defined in your statements "I wet it down good" and
"'tap in' tight". Additional moisture is absolutely not needed in "normal"
conditions and only the slightest bit of moisture is needed if you live in
someplace with no humidity. I've found that wood with 7-8% moisture content
will activate the glue just fine. The joint should not be so tight as to
drive the glue out while fitting it together. There is some narrow range of
fit which will work -- too tight and you don't have enough glue to do the
job, too loose and the glue has to fill the gap and loses strength (this is
true for all glues, not just the "gorilla" variety). Try it again and DON'T
wet it at all, make the joint 'push together' tight, and see what happens
then report back. I've used this stuff in very difficult glueups in hard
maple and other hardwoods and can state without hesitation that it sticks
fantastically well when used as intended.