Hi All:
Here is a great video showing how tough carbon fiber can be. 
Also notice how light it is. I can hardly roll my poly kayak up on its side at more than 90 pounds.
http://www.youtube.com/watch?v=7dtk818WSiU&feature=related
Jim
Peace through Victory - the only lasting peace
sledgehammer, rubber mallet.
Eh.
But how much inter laminar debonding just happened 
No doubt there was some damage at some level. Everything takes its toll.
Jim
Awesome looking boat! I fish from it.
Good point Riff.
Call me jaded, but all I could think of when I was watching that video is who made it: Philippines? Costa Rico? Mexico? Thailand? If heās beating on it like that, its disposable, which means he didnt pay for American labor. My 2 cents.
Erā¦deadblow hammerā¦not really a rubber mallet I guess.
Still. Beat a fiberglass one, or even plasticā¦it will bounce off I would think.
Now, beat it with full force, with a pointed objectā¦like a rock, THEN letās talk. There is a difference between a blunt impact, and sharp point impact. My main project couldnāt stop a 7.25mm round, but it will NEVER break under a hammer blow!
Stillā¦would like to have a CF kayakā¦those things are fāin heavy when the water turns to crap, you arenāt experienced, and have to drag the boat 3 miles in the sand.
Hey Jim: Have you done any reading on Soric as a core?
Hope they sell that one as a āfloor modelā with a discount. Iād hate to buy one and find out they did that to my beautiful carbon kayakā¦ :rolleyes:
JRL:
Just spent some time looking at Soric. Thanks for thinking
about it with me in mind. I have always thought poly honeycomb
would be the core of choice for a composite kayak. I had been
looking a Nida-Coreās scrimed honeycomb core, are any of you
using either of these products?
I have been trying to see the light (no pun intended) for the
vacuum infusion process for my project.
Please correct me if I am mistaken. 
It seems as though the resin uptake is significant for an
infusion process at 1 kg/m^2 or 2.2 lbs. My āyak (18ā tandem,
24"W w/12-14" sides) will have approximately 11 meters (6 hull +
5 deck) of core material. If that is right it will uptake an additional
11 kilos in resin. :eek: 11k*2.2lb = 24.2 lbs. of resin or
24.2 lbs/8.8 lbs/gal is 2.75 gallons of resin! :eek:
Is this correct? I thought it would be lots better (lighter) than that.
My assumptions come from this product sheet:
http://www.lantor.nl/files_cms/bestand/40993.pdf
(I just went back to review the sheet and it lists the impregnated density of Soric
at 600 kg/m^3. So 11yds * .25" = approx 3"; 36"/3" = approx.
1/12 of a cubic meter. 600kg/12 = 50kg! which is even worse at
110 lbs. What is wrong with this calculation?)
What can I expect for resin usage/weight if I infuse about 33
yds. of CF/Kevlar hybrid cloth? Is that 6 oz * 33 yds / 16 oz/lb = 12.375 lbs.?
Thatās 2 layers on the outside of hull
and 1 everywhere else, (inside of hull, in & out of deck) Will this layup work
or does it need to be the same in and out of hull for the core to work?
I am concerned about rock impacts at 6-8 NM/hr.
Iām sooo confused! :o
It looks as though prepreg is still the best option if I am to
build a light (40lbs) racing craft.
Thanks for letting think out loudā¦
Jim
CTJim
Iām interested in the Soric answers too - wonder if anybody else has used it.
I have done a few pieces and to say the least - its very interesting material. The first piece(s) were as mold reinforcement. WOW - it took 2 - 3 times the resin I expected - and I expected a lot.
They give a ratio that includes thickness of the Soric in your calculations. Did that.
Also - a very interesting property - it turned putty-like. As it took up the resin, you could work it and the material seemed to turn to a wet paper-macheā-like stuff.
Oh, its rock hard (sized for epoxy) but heavy - not bad for a mold - but not an ultralight!
I want to use it as core - so may lay up separately and try that then layup at B Stage (still green) in the second step - the mold.
As I play with it Iāll post if any more comes out. Maybe it needs its own thread?
Cheers - Jim
I thought thats how that stuff worked. Honestly, I would avoid it. Divynicell would be a better option if your trying to go light weight. Still looking forward to seeing your boat when your done with it.
I was also thinking about the room air pre preg mentioned in another thread. One of the benefits of oven cure pre preg is that you have a lot of time to make adjustments w/o it curing on you. Even better is that you can get it a little tackier if you hit it briefly with a heat gun. Im curious to see how the air cure pre preg will behave if your work time goes a little long.