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sebastian
 
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Default composite construction, strip canoe plans

ah again helpful comments (except from the self proclaimed ass :0))

i thought i had procured a really good deal on 40 yards of kevlar but
the guy flaked out on me so im going to have to poke around ebay until
i can find a nice roll of the stuff cheap ...it can be had for $5
yard if you shop around. if any of you have a roll of kevlar youre
looking to liquidate let me know...

ive been doing a lot of practicing making small layups with various
thicknesses of 5oz kevlar49. One thing that ive noticed is that a
single layer of epoxied kevlar is quite flexible but still very tough
so i was going to make a bunch of 1'x4' kevlar sheets by pressing the
epoxy impregnated kevlar between two boards covered with polyethylene
sheeting to keep the kevlar from sticking (maybe park my truck on the
boards to really squish out the extra epoxy). then ill use these
semi-rigid kevlar sheets to cover the the canoecraft mold stations.
the comment about the spacing being too far may be valid but with
sheer and keel cords on the sections i might be able to fudge it.
with that first layer of kevlar sheeting in place (held together with
5min epoxy) then i was going to layup more kevlar cloth on top of the
semi rigid sheets (with slow cure laminating epoxy) so that i can have
3 or 4 layers of kevlar total. Since kevlar is fuzzy miserable stuff
as a external surface, and not that stiff, ive got many pounds of 12k
high modulus carbon fiber roving and i was going to lay up one or two
layers on the outside all running the lnegth of the the canoe for
stiffness and also carbon is nicer/easier to patch than kevlar and its
god almighty light which is what im shooting for i really want my 15'
canoe to be no more that 30lbs. so the end product canoe will be 4
layers of kelvar with 2 layers of carbon fiber. i figure with a nice
stiff gunwhale maybe out of carbon fiber tubing (which i found an easy
way to make by winding roving onto metal mandrel) and some support
beams it might not fold up on me.

and the suggestion of making air chambers (sealed
hatches...brilliant)in the bow and stern is the way to go foam core is
going to be way too much hastle and ill have rigity from the carbon
fiber...

thanks folks...maybe ill post a pic or two if i make some headway on
the project...ive got the sections all plotted out with very clear
help from stevej...i just need to find a batten


rian Nystrom wrote in message ...
sebastian wrote:

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.


It won't necessarily sink, but it will float so low in the water that
you won't be able to paddle it. A foam core will not provide enough
buoyancy to make a difference. Either create sealed compartments (with
access hatches) or use float bags to provide the buoyancy you need.