<<You have longitudinal strength in triaxial where needed...
Don't really see how a resin filled seam weakens the structure as it is
part of the web of the I beam structure.>>
I'm familiar with sandwich construction, and I don't question that
you can make a world-class boat out of polycore.
I'm just fond of a boat that has some reasonable structural integrity
even before the glass goes on. A resin seamed tortured polycore
hull isn't going to hold much tension (or shape) prior to glassing.
Thanks for the nidacore reference, by the way. I need
to replace the bunk shelves in my current boat, and this looks like a
much better solution than the plywood I inherited.
- Mike
Robert wrote:
-You have longitudinal strength in triaxial where needed and extra
uni in concentrated areas. A bit of movement in the structure
shouldn't matter provided the material isn't brittle and the stress
and strain parameters coordinate and the bonding is good. Don't
really see haow a resin filled seam weakens the structure as it is
part of the web of the I beam structure.
regards
robert
g-- In harryproa@yahoogroups.com.au, Mike Crawford
<jmichael@g...>
wrote:
>
> << I actually prefer the resilience of the polycore to the
strength
of
> the Kiri as tests I have read indicate it is better under
collision>>
>
> I think that kiri or cedar would probably test differently than
balsa,
> but I'm still willing to buy the argument. For the sake of
discussion,
> let's say that polycore is stronger in collision. But what about
as a
> complete structure taking a pounding in a storm? That's a
different
> kind of strength. I'd have more faith in a strip-planked boat
with
good
> longitudinal strength throughout the entire hull, than in a cored
boat
> that's going to have resin-filled seams that won't offer as much
structure.
>
> That's really the crux of the matter for me. What's more
important:
> collision or pounding? I'm personally more concerned about the
latter,
> but there's clearly no right answer.
>
> Of course, if tortured polycore could save me a few hundred kg,
and/or
> a thousand hours, I'd put the intellectual argument aside and jump
on board.
>
> - Mike
>
>
>
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