Message-Id: <338EF3F6.38D7@boi.hp.com>
Date: Fri, 30 May 1997 09:36:22 -0600
From: Bill Blohm <bblohm@boi.hp.com>
To: baidarka@lists.intelenet.net
Subject: Laminated ribs, etc..
Here's the meat of what prompted my question about
using a different construction method than what the
designer specifies.
I know I've got some terms, i.e. strakes, wrong, but
for the life of me I just can't remember the proper
term for the longitudal parts of the frame.
I'm thinking of using my G. Dyson plans, but laminating
the ribs, strakes, etc. up. Given the stocks of wood
hereabouts and all, that seems the best way to get a
strong framework of good wood.
What I envision doing is basically making a jig, with
large dowels going into holes at points where each bend
in the Al frame is. That way, the thin strips would
bend around in the same rate as the Al in the drawings.
I'd also laminate up the long strips running fore and
aft, staggering the butt joints over the whole length
of the lamination. (These longitudal "strakes" would be
transfered to a paper template first, to take into
account the curves, if any, in the run.)
The questions I have are:
1) Recommendations for a good waterproof glue for the
lamination process? Resorcinol?
2) Being laminated, the individual members will be fairly
strong. However, what would the assembled boat be like,
wrt flexibility? I.e. Al tubing bent into a certain rib
shape will be "hard" to flex as a whole. Would the
laminated up version of the rib be as stiff? Or would it
be springier, easier to bend in and out between the
chine bends?
3) Even if the frames are individually springier, when they
are assembled into the framework of the boat, will they
then be stiff enough, with the longitudal strakes now
reinforcing and thus providing the requisite stiffness?
I visualize the laminations running the shape of the rib,
not as if cut out of plywood. That is, if you look at the
rib, it would look as if it was cut out from a tree trunk
with that shape around, with all the growth rings following
the shape of the rib.
Bill B.