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Bulkhead & Hatch Q: A correction
By:Paul G. Jacobson
Date: 11/21/2001, 6:26 pm

So, after i said: "If you put 2, 3 or 4 layers of glass on both sides of
your bulkheads no one would blame you for your extravagance."

" You are foolish to believe that you will need to reinforce the bulk heads to
: such an extent. The 3mm ply will be just fine and you only need a fillet
: of glass fiber thickened epoxy on both sides. The strenght in the verticle
: forces is extreamly high. . . ."

So I'll modify my original answer to reflect that at least one person has proven my forecast wrong. :)

That should teach me to avoid using such absolute terms as "no one". Hmm, maybe I should have said "there aren't *a lot* of people who will blame you for reinforcing ...etc."

As for the stresses on the bulkhead: on most well designed boats there is little need for a bulkhead. A deck beam, strong cockpit coaming or strong deck seems to give the necessary strength for cross bracing. In a canoe this bracing would be provided by thwarts and/or seats. So, since the hull and deck can support themselves without the bulkhead, it is unlikely they would put much stress on the bulkhead in the first place.

My worry is with the unexpected forces that might hit the wide side of such a thin plywood piece. The 1/8th inch plywood I have is not aircraft grade, and I can easily snap a 1-2 foot long piece in half if I put my weight on it. Of course I'm a good bit over the average size. Personally, I'd want to make sure that if the forward bulkhead if it was anywhere close to the front end of cockpit (and it should be to keep down water volume should the cockpit flood) that I wouldn't put my foot through it should my foot slide off the footpegs. Unlikely? True, but I worry about these things. :)

Another thought The added weight of the glass is inconsequential, and having it on ensures that you'll have an even coating of resin. The thickness of the cloth serves as a thickness gauge for the coating. If the glass is wetted out evenley, and the excess removed with a squeegee, having a piece of glass cloth on there that is .003 inches thick ensures that the resin is also that thick.

Just a short note from someone who sometimes is VERY foolish, and who likes to wear funny hats. :)

PGJ

Messages In This Thread

Strip: Quick Bulkhead & Hatch Question
Jon Murray -- 11/20/2001, 10:27 pm
What about bulkhead weight?
Paul Streitman -- 11/26/2001, 2:44 pm
Re: What about bulkhead weight?
Bruce Schultz -- 11/28/2001, 8:11 am
Re: Strip: Quick Bulkhead & Hatch Question
JimPeterson -- 11/22/2001, 12:44 pm
Re: Strip: Quick Bulkhead & Hatch Question
LeeG -- 11/21/2001, 8:25 am
Veneer Bulkhead
Andreas -- 11/22/2001, 11:47 am
Bulkhead Idea
Jon Murray -- 11/21/2001, 3:04 pm
Re: Bulkhead Idea
Tom Johansen -- 11/21/2001, 11:38 pm
Re: Bulkhead Idea
LeeG -- 11/21/2001, 10:33 pm
Re: Strip: Quick Bulkhead & Hatch Question
Chris Menard -- 11/21/2001, 7:44 am
Re: Strip: Quick Bulkhead & Hatch Question
Mitch Isoe -- 11/21/2001, 11:55 am
Re: Strip: Quick Bulkhead & Hatch Question
Paul G. Jacobson -- 11/21/2001, 12:02 am
Re: Strip: Quick Bulkhead & Hatch Question
Tom -- 11/21/2001, 12:41 am
Bulkhead & Hatch Q: A correction
Paul G. Jacobson -- 11/21/2001, 6:26 pm
Re: Bulkhead & Hatch Q: A correction
Tom Johansen -- 11/21/2001, 11:16 pm
Foolish?
Mike Nicholson -- 11/21/2001, 9:22 am
Re: conversationaly speaking..
LeeG -- 11/21/2001, 1:29 pm
Re: Strip: Quick Bulkhead & Hatch Question
Greg Morse -- 11/20/2001, 11:59 pm
Re: Strip: Quick Bulkhead & Hatch Question
Jim Kozel -- 11/21/2001, 11:24 am
Thanks Greg and Jim - Just What I Needed! *NM*
Jon Murray -- 11/21/2001, 3:06 pm