View Single Post
  #36   Report Post  
posted to alt.sailing.asa
Maxprop
 
Posts: n/a
Default What boat for me? (long)


"DSK" wrote in message
...


I have a buddy who used to have a 100% chopper gun canoe. Weighed about
200#.


That must have been fun to portage.

OK, it may be that you've spread the compression over a large enough area
that it's not a problem. But there will be a concentration of stress at
the edge facing the direction the line pulls from.


It was installed three years ago and so far no evidence of any indentation
on the forward edge (facing the mast--it's a main halyard stopper).

Hey if it works, it must have been done right!


Beginner's luck, and a bit of overkill, according to the glass wizard at our
marina.

From what I've read, the issue is bonding the skin to the core. Airplanes
use some exotic technology to achieve this, and it could be done (I
believe it has been done) with some high end boats for critical
components. The easiest way to get a good bond is to fill the cell with
resin, but then you don't have such a light structure any more!


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. 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. Hexcel warranted the skis against delamination from the core for
life. My wife had a pair--they were light and responsive, according to
her--and we eventually threw them away after they hung in the rafters of the
garage for a decade or so after she'd gotten several new pairs of skis.
They never delaminated, but all my older French skis did--Rossignol, Dynamic
and others all used wood cores.

Max