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Re: Strip: Carbon Fiber on the Inside
By:Mike Savage
Date: 12/1/2011, 1:57 pm
In Response To: Strip: Carbon Fiber on the Inside (Bryan Hansel)

: I built a canoe this summer with carbon fiber on the inside.
: Recently, a wind storm picked it up off the ground where it was
: stored and bashed it up against a tree. The wind was bad enough
: that it tossed a couple of sawhorses halfway across the lawn.
: Where the boat hit the tree, the glass on the outside cracked,
: which I would have expected. On the inside, the carbon fiber
: split and fractured. I've never seen this much damage on the
: inside of a boat from one impact even from times that I landed
: my wooden kayak on a boomer and needed to do repairs because of
: that. I'm not sure I'd use carbon fiber on the inside again
: without covering it with glass.

: Thoughts?

Hi Bryan,
Sorry to hear about the damage, I go nuts with rope when there's high winds forecast. If I'm paranoid, it looks like a giant spider went webbing. :D

CF is very strong in tension but weak in compression along the fibre, when the canoe hit the tree, the CF was put under high compression loads and failed. There's also an imbalance in 'strength' if the CF is only on one side, the glass stretches a bit more than CF letting the outside stretch and putting the CF in compression. CF on the outside as well might have stabilised the 'strengths' and not failed. Though smacking into a tree never does a canoe any good.

Mike Savage
South West Cork

Messages In This Thread

Strip: Carbon Fiber on the Inside
Bryan Hansel -- 11/30/2011, 9:57 am
Re: Strip: Carbon Fiber on the Inside
Charlie -- 11/30/2011, 10:51 am
Re: Strip: Carbon Fiber on the Inside
Malcolm Schweizer -- 11/30/2011, 1:23 pm
Re: Strip: Carbon Fiber on the Inside
Bryan Hansel -- 11/30/2011, 3:37 pm
Re: Strip: Carbon Fiber on the Inside
StephenHJ -- 11/30/2011, 1:37 pm
Re: Strip: Carbon Fiber on the Inside
Bryan Hansel -- 11/30/2011, 3:38 pm
Re: Strip: Carbon Fiber on the Inside
ScottBaxter -- 11/30/2011, 7:22 pm
Re: Strip: Carbon Fiber on the Inside
ancient kayaker -- 11/30/2011, 11:22 pm
Re: Strip: Carbon Fiber on the Inside
Bryan Hansel -- 12/1/2011, 1:59 pm
Re: Strip: Carbon Fiber on the Inside
Brian Nystrom -- 12/1/2011, 6:30 am
Re: Strip: Carbon Fiber on the Inside
Mike Savage -- 12/1/2011, 1:57 pm
Re: Strip: Carbon Fiber on the Inside
Bryan Hansel -- 12/1/2011, 2:03 pm
Re: Strip: Carbon Fiber on the Inside
Allan -- 12/1/2011, 4:51 pm
Re: Strip: Carbon Fiber on the Inside
Bryan Hansel -- 12/1/2011, 5:28 pm
Re: Strip: Carbon Fiber on the Inside
Robert N Pruden -- 12/1/2011, 6:55 pm
Re: Strip: Carbon Fiber on the Inside
Etienne Muller -- 12/2/2011, 3:21 am
Re: Strip: Carbon Fiber on the Inside
Kirk Briggs -- 12/3/2011, 9:44 am
Re: Strip: Carbon Fiber on the Inside
Paul G. Jacobson -- 12/9/2011, 2:30 pm