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Re: S&G: Stiffness compared to strip
By:Nick Schade - Guillemot Kayaks
Date: 6/26/2013, 4:33 pm
In Response To: Re: S&G: Stiffness compared to strip (Dan Caouette (CSCWC))

I should have defined the "stiffness" in question. The stiffness I'm discussing is overall, on-the-water flexing. Some paddlers prefer a stiff kayak. It can be argued that stiffer boats are faster as less paddling energy is wasted due to the flexing of the hull/deck. It's also argued that they are more responsive. That's one reason a majority of commercial race boats strive for high stiffness with low weight.

Again we are left with a question. Is "over all" stiffness what it would take to bend the whole boat in distributed loading: i.e. each end of the boat sitting on saw horses, with a load in the middle. This stiffness is not defined solely by the material of the boat, the design of the boat will make a difference and the difference between okoume and strips is probably negligible if not zero.

If you are asking about local loading: which boat will flex more due to pressure on the footpegs, then it is hard to know without testing. I think cedar is stiffer along the grain, and okoume may be stiffer across the grain. The boat with the stiffer core will be stiffer, but how the load is applied will determine how much flex is experienced.

FWIW, a fiberglass/wood-core boat is likely to be stiffer than carbon fiber for local loading and probably distributed as well.

Messages In This Thread

S&G: Stiffness compared to strip
Dan Caouette (CSCWC) -- 6/25/2013, 2:26 pm
Re: S&G: Stiffness compared to strip
Matt Jakubek -- 6/25/2013, 2:49 pm
Re: S&G: Stiffness compared to strip
Etienne Muller -- 6/25/2013, 2:53 pm
Re: S&G: Stiffness compared to strip
Dan Caouette (CSCWC) -- 6/26/2013, 9:18 am
Re: S&G: Stiffness compared to strip
Etienne Muller -- 6/26/2013, 10:16 am
Re: S&G: Stiffness compared to strip
Malcolm Schweizer -- 6/25/2013, 3:21 pm
Re: S&G: Stiffness compared to strip
Nick Schade - Guillemot Kayaks -- 6/25/2013, 4:40 pm
Re: S&G: Stiffness compared to strip
Marc Upchurch -- 6/25/2013, 6:06 pm
Re: S&G: Stiffness compared to strip
Dan Caouette (CSCWC) -- 6/26/2013, 9:03 am
Re: S&G: Stiffness compared to strip
Nick Schade - Guillemot Kayaks -- 6/26/2013, 4:33 pm
Re: S&G: Stiffness compared to strip
ancient kayaker -- 6/26/2013, 11:32 pm
Re: S&G: Stiffness compared to strip
Nick Schade - Guillemot Kayaks -- 6/27/2013, 9:29 am
Re: S&G: Stiffness compared to strip
Bill Hamm -- 6/30/2013, 2:24 am
Re: S&G: Stiffness compared to strip
Robert N Pruden -- 6/27/2013, 4:55 pm
Re: S&G: Stiffness compared to strip
Erik -- 6/25/2013, 8:12 pm
Re: S&G: Stiffness compared to strip
ancient kayaker -- 6/25/2013, 9:01 pm
Re: S&G: Stiffness compared to strip
Dan Caouette (CSCWC) -- 6/26/2013, 9:30 am
Re: S&G: Stiffness compared to strip
Bill Hamm -- 6/30/2013, 2:21 am
Re: S&G: Stiffness compared to strip
Dan Caouette (CSCWC) -- 6/26/2013, 9:17 am
Re: S&G: Stiffness compared to strip
Bill Hamm -- 6/26/2013, 1:53 am
Re: S&G: Stiffness compared to strip
Tony G -- 6/26/2013, 9:27 am
Re: S&G: Stiffness compared to strip
Dan Caouette (CSCWC) -- 6/26/2013, 9:38 am
Re: S&G: Stiffness compared to strip
john Messinger -- 6/26/2013, 11:49 am
Re: S&G: Stiffness compared to strip
Etienne Muller -- 6/26/2013, 12:14 pm
Re: S&G: Stiffness compared to strip *PIC*
Rob Macks/Laughing Loon CC&K -- 6/26/2013, 12:20 pm
John, are you talking about boats? *NM*
Rob Macks/Laughing Loon CC&K -- 6/26/2013, 12:50 pm
Where's the tip jar?!
Dan Caouette (CSCWC) -- 6/26/2013, 1:04 pm
Re: Where's the tip jar?!
john Messinger -- 6/27/2013, 8:37 am
Re: S&G: Stiffness compared to strip
Mike Savage -- 6/27/2013, 6:34 pm
Re: S&G: Stiffness compared to strip
Kurt Maurer -- 6/27/2013, 9:35 pm
Re: S&G: Stiffness compared to strip
Mike Savage -- 6/28/2013, 4:49 pm
Re: S&G: Stiffness compared to strip
Bill Hamm -- 6/30/2013, 2:31 am
Re: S&G: Stiffness compared to strip
Mike Savage -- 7/1/2013, 4:46 pm
Re: S&G: Stiffness compared to strip
ancient kayaker -- 6/28/2013, 7:14 pm
Re: S&G: Stiffness compared to strip *PIC*
Sam McFadden -- 7/1/2013, 11:54 am
Re: S&G: Stiffness compared to strip
Bill Hamm -- 7/2/2013, 9:11 am
Re: S&G: Stiffness compared to strip
Sam McFadden -- 7/2/2013, 10:43 am
Re: S&G: Stiffness compared to strip *PIC*
ancient kayaker -- 7/2/2013, 6:43 pm
Re: S&G: Stiffness compared to strip
Etienne Muller -- 7/1/2013, 1:31 pm