"DSK" wrote in message
.. .
I have a buddy who used to have a 100% chopper gun canoe. Weighed about
200#.


Maxprop wrote:
That must have been fun to portage.


Didn't. It rode on a ski boat trailer. The guy worked in a fiberglass
plant making bathtubs & such, and brought in a canoe to use as a mold
plug. He wanted to make a sailboat but the canoe was not enough of a
success to justify the work.


I found a website which claimed that Yamaha built a few prototype
sailboats with honeycomb aluminum coring throughout the hulls and on the
flats of the decks.

Yamaha builds some cool boats. They're currently making a 30 (IIRC) and a
33' sport boat that looks at least as fast and more practical than
anything else on the market, unfortunately I've lost the web page & can't
find it again.

There have been some "superyachts" built with structural panels (floors &
partial bulkheads, I think) with aluminum honeycomb core.

... It was great, according to the author, but the cost would have been
prohibitive. As for bonding the skins to the honeycomb, Hexcel Skis,
which used the technology, used to laminate the skins first and then
apply a slurry of resin and finely chopped fibers to the surface, into
which the honeycomb was pressed. Both inner skins were applied
simultaneously and bonded under high pressure--I vaguely tend to recall
that it was about 150psi.

The ones I read about used a different adhesive than laminating resin to
glue the core to the skin, vacuum-bagged, then post-cured the whole
structure (as I understood the process). It's not a mature technology, but
it's hard to imagine what's coming up next by the time they get this stuff
completely figured out.

I've been working with some carbon fiber & foam core laminations, learning
enough to make a dinghy out of the stuff. It's amazing, weighs nothing. A
friend had a new Int'l 14 hull made in a pro shop, then brought it home to
install the hardware. Could pick it up with one hand and throw it across
the yard like a huge paper plane!

I've wondered why carbon fiber hasn't been exploited more as lamina in
production boat hulls and decks, such as class racers, etc. If utilized in
mass quantities, the high cost factor should be mitigated somewhat. And how
about a carbon honeycomb core? Shouldn't present the bonding issues that
aluminum honeycomb did.

Max

Maxprop wrote:
I've wondered why carbon fiber hasn't been exploited more as lamina in
production boat hulls and decks, such as class racers, etc. If utilized in
mass quantities, the high cost factor should be mitigated somewhat.

It is being used more & more for spars, especially sprits &
spinnaker poles, also foils. For example Hobie Cats have
been using carbon fiber rudder blades for years.

The cost of the raw material just took a leap upward,
supposedly the military is buying up 110% of production for
the next few years. Fortunately I had already bought some
rolls of woven carbon for my dinghy project, I think I have
enough.

.... And how
about a carbon honeycomb core? Shouldn't present the bonding issues that
aluminum honeycomb did.


There is an expanded carbon core material, but it has to be
carved to shape. Difficult to work with. And it's *real*
expensive.

Fresh Breezes- Doug King