Boat Building Forum

Find advice on all aspects of building your own kayak, canoe or any lightweight boats

Re: Newbie contruction review, hardwood difs
By:Sam McFadden
Date: 4/25/2002, 11:27 am
In Response To: Re: Newbie contruction review, hardwood difs (Mike Loriz)

Mike,

I like your view of wood. In the days of traditional wood construction, much of the west coast fishing fleet was made mostly of cedar (lots of port orford), and some of them are still around. In the early '70's the Gougeon brothers (WEST Syst.) were building wood epoxy boats that were stronger, stiffer (in sailboats stiffness is a very good thing), lighter, and more durable than the vast majority of their contemporary glass/carbon/Kevlar counter parts. In the early '80's they were building wood/epoxy wind turbine blades that had much better properties than their aluminum or fiber composite counterparts - the aluminum blades tended to self destruct at much shorter service times. As an aside to this, I do recall a 747 losing its tail in mid flight, someplace in Asia if I remember correctly. My point about Merlin's construction was not intended to promote the composite sandwich approach, but to emphasize that there are many possible solutions to the same structural problem, and that any one of those solutions must be self consistent to work well.

The common view of glass/epoxy/cedar strip kayaks being sandwich structures is a useful simplification of the situation, and is as accurate an explanation as most people need. But in the past, some have argued that all one has to do is look at the low values of across-the-grain properties, realize that the wood does not contribute strength to the sandwich, and presto(!); the obvious answer is to eliminate wood, and add a bunch of glass/epoxy. But careful analysis and experimental evidence shows that we are not dealing with a classic sandwich structure, so the logic is not strictly valid. The resulting structure may be fine, as long as you don't mind working with thin strips and lots of glass/epoxy, but it is a solution to a non-problem. I understand that this is not your position, but it illustrates some of the pitfalls of making assumptions and simplifications in analysis.

Thanks for the pleasant discussion,
Sam

Messages In This Thread

Launching: photos?
Mike Loriz -- 4/23/2002, 9:16 pm
Another pic
Mike Loriz -- 4/24/2002, 10:40 am
Newbie contruction review, hardwood difs
Mike Loriz -- 4/24/2002, 2:18 pm
Re: Newbie contruction review, hardwood difs
Sam McFadden -- 4/25/2002, 12:56 am
Re: Newbie contruction review, hardwood difs
Mike Loriz -- 4/25/2002, 9:17 am
Re: Newbie contruction review, hardwood difs
Sam McFadden -- 4/25/2002, 11:27 am
Re: Newbie contruction review, hardwood difs
Andy -- 4/27/2002, 11:09 pm
Re: Newbie contruction review, hardwood difs
Sam McFadden -- 4/28/2002, 9:52 pm
Re: Newbie contruction review, hardwood difs
Mike Loriz -- 4/25/2002, 1:07 pm
Re: Newbie contruction review, hardwood difs
Sam McFadden -- 4/25/2002, 11:39 pm
Re: Newbie contruction review, hardwood difs
Mike Loriz -- 4/26/2002, 10:15 pm
Other species
Sam McFadden -- 4/27/2002, 12:09 pm
Re: Other species
Mike Loriz -- 4/28/2002, 9:10 pm
Re: Other species
Sam McFadden -- 4/28/2002, 9:45 pm
Re: Other species *Pic*
Nick Schade - Guillemot Kayaks -- 4/29/2002, 9:14 am
Re: Other species
Sam McFadden -- 4/29/2002, 5:27 pm
Go with the old wood/canvas canoe model
Paul G. Jacobson -- 4/27/2002, 12:48 am
Re: Go with the old wood/canvas canoe model
Mike Loriz -- 4/28/2002, 8:49 pm
Re: All Wood
Nick Schade - Guillemot Kayaks -- 4/26/2002, 10:06 am
No angels, pins or dancing needed :)
Paul G. Jacobson -- 4/25/2002, 9:10 pm
Re: No angels, pins or dancing needed :)
Mike Loriz -- 4/26/2002, 10:04 pm
Re: No angels, pins or dancing needed :)
Sam McFadden -- 4/25/2002, 11:24 pm
I would like jump in here
David Hanson -- 4/25/2002, 4:51 pm
What about using 1/8" Red Elm for strong strips?
John Monfoe -- 4/26/2002, 7:22 am
Re: What about using 1/8" Red Elm for strong strip
Mike Loriz -- 4/26/2002, 9:42 pm
Re: What about using 1/8" Red Elm for strong strip
John Monfoe -- 4/27/2002, 6:17 am
Re: What about using 1/8" Red Elm for strong strip
David Hanson -- 4/26/2002, 11:44 am
Use both feet :)
Paul G. Jacobson -- 4/25/2002, 9:58 pm
Re: I would like jump in here
Mike Loriz -- 4/25/2002, 9:40 pm
Now we are getting somewhere
David Hanson -- 4/26/2002, 11:36 am
Re: Now we are getting somewhere
Mike Loriz -- 4/26/2002, 9:33 pm
Re: I would like jump in here
Andreas -- 4/26/2002, 10:44 am
Re: I would like jump in here
Mike Loriz -- 4/26/2002, 9:04 pm
Re: The Wood Matters *Pic*
Nick Schade - Guillemot Kayaks -- 4/26/2002, 12:48 pm
Its a bird its a plane its a .....?
!RUSS -- 4/26/2002, 5:34 pm
Re: Its a bird its a plane its a .....? *Pic*
Nick Schade - Guillemot Kayaks -- 4/28/2002, 11:55 am
Re: The Wood Matters - You are right
Andreas -- 4/26/2002, 2:47 pm
Re: Credit *Pic*
Nick Schade - Guillemot Kayaks -- 4/26/2002, 5:16 pm
Re: Credit
Andreas -- 4/26/2002, 6:16 pm
Re: Delamination
Nick Schade - Guillemot Kayaks -- 4/28/2002, 12:41 pm
Re: Delamination
Mike Loriz -- 4/28/2002, 10:43 pm
Re: Delamination
Sam McFadden -- 4/30/2002, 12:08 am
Re: Delamination
Mike Loriz -- 4/30/2002, 12:37 pm
Calculations
Sam McFadden -- 4/26/2002, 12:43 pm
Re: Calculations
Mike Loriz -- 4/26/2002, 9:19 pm
Re: Newbie - Not!
Chip Sandresky -- 4/24/2002, 3:05 pm
Re: Newbie - Not!
Mike Loriz -- 4/24/2002, 7:06 pm
Re: Newbie - Not!
Steve Frederick -- 4/24/2002, 10:22 pm
Re: Newbie - Not!
Mike Loriz -- 4/25/2002, 8:44 am
Re: Launching: photos?
Mike Loriz -- 4/24/2002, 10:35 am
Re: Launching: photos?
Nick Schade - Guillemot Kayaks -- 4/24/2002, 9:35 am
Re: Launching: photos?
Bobby Curtis -- 4/23/2002, 11:14 pm
Re: Launching: photos?
Mike Loriz -- 4/24/2002, 7:00 pm
Doh!!
Sam McFadden -- 4/23/2002, 11:01 pm
Re: Launching: photos?
daren neufeld -- 4/23/2002, 10:29 pm
Great!
Sam McFadden -- 4/23/2002, 10:55 pm
Re: Great!
Mike Loriz -- 4/24/2002, 6:57 pm
Re: Launching: photos?
John Schroeder -- 4/23/2002, 10:17 pm
Re: Launching: photos?
Ronnie -- 4/23/2002, 9:28 pm