DIYbanter - View Single Post - Replacing gunnel on my canoe (slightly OT)

wrote:

On Fri, 16 Jul 2004 03:17:41 -0400, (J T)
wrote:

Thu, Jul 15, 2004, 11:48pm lid (J.*Clarke) says:
snip On a canoe, I'd use resorcinol myself, but epoxy should be fine.
I wouldn't trust _any_ PVA glue on a stressed part of any boat. Having
your glue let go at sea can ruin your whole day snip

OK, I'll bite. Why would you imply that a PVA glue would "let go
at sea" on a canoe, stressed part or not? tt's not going to be
submerged, at least not in normal use. And, it's not like wood glue has
never been used in boatbuilding before. I'd imagine it'll wind up with
a varnish, or other protective coating too, which will keep moisture
away from the glue. Do you know of a stressed PVA glue joint that "let
go at sea"?

Hey Ron, you're the resident boatbuilding expert, what's your
opinion?

JOAT

I ain't Ron. I'm not even a boatbuilder. but I do know that PVA glues
have a reputation for creeping under stress and for not being terribly
waterproof. after all, they are formulations of poly.VINYL.acetate.
vinyl beinc a plastic, and plastic being a word meaning easily
deformed.

While one definition of "plastic" is "easily deformed" the term encompasses
a vast range of materials these days, and some of them are not nearly as
easily deformed as you might think.

PVA creeps because that's one of its properties, not because it's plastic
per se. Epoxy is also a plastic and it is much less subject to creep.

--
--John
Reply to jclarke at ae tee tee global dot net
(was jclarke at eye bee em dot net)