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Jim Conlin
 
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Default composite construction, strip canoe plans

To build a canoe in 1/8" Core-Cell sandwich, I don't think it's be practical
to build it as a strip boat, where the order of constructions is:
- plank over station molds with strips, edge-glued
- fair the strips
- apply out glass (or ??) skin, set in epoxy
- remove from station molds
- fair inside
- glass (or ??) inside

For a thin foam core boat with this approach, I think you'd need to use
station molds spaced less than 6" apart. Without that, the strips would be
wayward and would lack the stiffness to stand up to the fairing step. This
becomes a MASSIVE lofting job.

Instead, the way that commercial foam-core boats are built involves a full
female mold in which the boats are built from the outside skin inward. Some
builders might be infusing these days. THis takes an investment in tooling
which is not practical for a one-off boat.


sebastian wrote:

thanks to the folks who provided feedback on my lofting question.

Im going to build the ranger {15'} instead of the prospector (16')
canoe, and im going to construct it with a kevlar-carbon layup instead
of wood strip. Can anyone suggest the best way for me to adjust the
size of the stations to accomodate the thin, uniform thickness of the
composite layup compared to the wood. I'm going to use 3 layers of
5oz kevlar and one or two layers of unidirectional carbon so im
guessing it will be about 1/8"-3/16" thick max. how thick is the wood
stripping and is it relatively uniform in thickness ie can i just add
1/2" to all my patterns and have a decent work around?

also i would like to not use foam core in my layup for simplicity and
minimizing weight...but will the canoe sink like a rock if its swamped
if its just kevlar/carbon/epoxy? I am wondering if i should use a
1/8" atc core cell between layers of kevlar...for buoyancy and
stiffness.