58944Re: [bolger] Re: replace epoxy with resorcinal??
- Oct 26, 2008titanicslim wrote:
>I Like resorsanol glue. I like epoxy but hate to use it. I also
> I'm sure that is correct, and the main reason a resorcinol joint must
> be very strongly clamped. It is nothing at all like epoxy and other
> resins. (Which reminds me: might the failed joints you mention
> sometimes in fact be plastic resin glue- PRG? Weldwood.)
> --- In firstname.lastname@example.org <mailto:bolger%40yahoogroups.com>, "Jon
> & Wanda(Tink)" <windyjon@...> wrote:
> >> resorcinal gets brittle over time. The same reason old chair joints
> > fail over time.
> > Jon
like tight bond three.These are for the most part the glues I have
experience with. I'm sure there are others out there that like other glues.
A little on where my experience comes fro is that I am older than
dirt. I am dumb as a stump. A good friend says you may be dumb Doug, but
you have the best memory of anyone I know, so dumb or not you know a lot
of stuff. So this is some of what I remember about glue and wood. Any
talk of boat building glue without talking about wood is a complete
waste of time. I think!!
In the late 1930's when I was a small boy everyone in our neighbor
hood had a half rotten old boat in the water and a new one under
construction in the back yard. The boats were mostly sharpies but more
and more people were copying Owens yacht companies power boats as well
as the type of construction. The sharpies had almost no glue in them
and were held to together with nails and some screws. The new boats
were glue and screws with a few nails. The glue was Casco a cheap glue
and used above the water line. From a little above the waterline down
was used resoranol glue and bronze screws. There was no stainless steel
or it was very expensive and hard to come by and completely not trusted.
Speaking of Bronze screws, The wood including planking was hard and
close grained and there were no electric screwdrivers that would have
been laughed at by boat builders because the could not have been used to
drive screws into that harder wood. Screws were waxed or soaped and
driven in with the tremendous force applied by the Brace and bit. They
were big and long with a large root diameter. The glue held the wood in
place only in the six inch long section between screws. I used to hear
all the time that screws were not needed after the glue hardened and it
may be so, but I have known any one to take them all out after gluing.
WWII brought plywood onto the scene, a huge change. We laughed at
the landing barges built by Owens and many said they hoped the war did
not last long because all the landing barges were going to fall apart.
Peoples earlier experience with plywood had been a disaster and a little
of that attitude falsely exists today. The resorsanol glue held up in
many of those barges for as much as fifty years and the amazing thing is
so did the Casco glue that held the laminations together. Resorsonal
glue was not used to laminate plywood during the war years but excellent
wood was, and the laminates in the plywood were excellent as well. At
the time we didn't know that because we did not have modern wood to
compare it to. It's kind of like the Eskimo that doesn't know he is
cold because he has never been warm. And thats a well worn phrase!!
In 1946 I was 12 years old and helping my older friends build punts
and duck boats at that time the wood was excellent it was still coming
out of the deep forests where trees had struggle for light and
nutrients. These trees grew slow with narrow rings and even the pulpy
wood was tough and rot resistant. I am speaking here of boat lumber
there was plenty of trash wood going into houses and even so most are
Today most of us home builders are using the junk wood that comes
from big box stores that is of a quality suitable to make paper from.
Do you really need a strong glue to hold wood together that is so weak
that the glue can pull chunks of wood off. If ripped apart?? Seems to
me that boats of stitch and glue construction need epoxy because she
needs to be built with epoxy on glass in joints and I don't believe any
other glue can be used in this way. I think that epoxy and glass are
important for a covering to protect such sorry wood. If a boat is being
built to go to sea the best wood and glue as well as good screws. By
best glue I am thinking of epoxy and should be sheathed in glass and
epoxy as well as even carbon fiber in areas that are vulnerable. Good
wood can still be gotten but its a chore.
I stated earlier that I am dumb if you don't think so, consider
this I built my Elver from really nice long leaf yellow pine and then
used big box plywood for bottom ,decks and bulkheads and when it has
all rotted away my planking will still be there. I would say, either
build your boat out of cheap wood and cheap everything else or build it
out of all good stuff I would not mix and match.
I'd say the best glue may not be the best for a boat to be used for
dinking around and the best may be what's easy to use. This of course
only applies if the glue is good enough, to do the job. Really and
truly the cheapest glue may be epoxy if you have a good way to mix very
small amounts of it. Of course it you think ahead you may be able to
use the left over to glue something else or coat something for
protection. I find it hard to construct things in epoxy because I am
always tearing my gloved or clamping the finger tips of the between to
pieces of wood and pulling off the finger tips.
If I go to sea in a boat I want good screws as well as good glue in
it because I don't want to wake up at 3A.M. wondering if a seam has
pulled apart. I have absolute confidence in a seam that is screwed and
glued and covered with a couple layers of glass and epoxy and I get a
warm fuzzy feeling about that same boat with no through hulls. The same
boat with hatches and topside built with the same strength and care as
I guess it's irrational but somehow I don't get the same secure
feeling out of a glass boat. There is something about all the different
layers of different materials that in my mind instills confidence in a
wood glass composite boat.
Even a steel or aluminum boat give and instants of fright when there
is a sudden thump on the hull. My mind instantly goes to a little
mistrust of the mysteriousness of the welds hold the seams together.
AS a young man I sailed on boats where you woke up and felt the cabin
sole for water every morning that is a great relief when none is found,
but doe's not show a lot of confidence before the fact.
Fear has caused a lot of tragedies at sea and most of it is cause by
some lack of confidence in some part of a boat, the mind jumps to the
wrong conclusion and grave mistakes are made.
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