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Re: Skin-on-Frame: Alternative flotation material
By:Mike Savage
Date: 8/24/2011, 8:09 am

: I think some sort of floatation is a good idea. I know in my
: strip-kayak I hardly ever even look into the fore and aft
: compartments. They leak a little, hatch, fittings... and drain
: out of the same holes.
: Putting some kind of floatation in there shouldn't hurt, and in a
: serious bull breach could be a life saver.

: I think float bags in skin boats and wood and glass boats that have
: no bulkheads is smart. But as durable as a good float bag is,
: whatever might cut, rip, breech a hull could also breech the
: bag.

: Two ideas.
: 1. Empty soda bottles. These things are very tough and almost free.
: They can take about 150 psi. A mesh bag of these wouldn't fill
: every crevice, but could fill enough. This is probably usable
: only in a wood kayak like mine where you'd just like some
: set-n-forget insurance in the holds.

: 2. The solid material with the smallest density is areo-gel,
: probably too expensive to use in a kayak. Close to aerogel and a
: lot cheaper is the green foam blocks used by florists. This
: stuff doesn't sponge up water, could be placed into a dry bag
: and crammed into the compartments (in a skin boat you could
: hammer down any bulges) --then if you get a rip (hull breach)
: even if it rips into the bag of green foam blocks--they'd still
: keep you afloat. Voids would be at a minimum (and anyone who's
: ever experienced what a couple of inches of water in the cockpit
: can do to stability would understand how helpful this could be
: in an emergency.)

Hi Will N,
A "trick" with airbags and SoF's is to get the airbags too big. That way the bag can mold itself around the stringers and ribs for maximum displacement. It also means you don't need to inflate the bag to the point of the bag's skin being taut and would let any pointy impactmove the bag's skin rather than puncture it.

One of the problems with more solid buoyancy is the drying out of the kayak. With air, you just need to deflate the bag for the kayak to air out, with foam you have to take it out.

Mike Savage
South West Cork

Messages In This Thread

Skin-on-Frame: Alternative flotation material
Sean D -- 8/22/2011, 9:41 am
Re: Skin-on-Frame: Alternative flotation material
Brian Nystrom -- 8/22/2011, 12:54 pm
Re: Skin-on-Frame: Alternative flotation material
StephenHJ -- 8/22/2011, 1:13 pm
Re: Skin-on-Frame: Alternative flotation material
Sean D -- 8/22/2011, 2:13 pm
Re: Skin-on-Frame: Alternative flotation material
Bill Hamm -- 8/23/2011, 2:22 am
Re: Skin-on-Frame: Alternative flotation material
Les Cheeseman -- 8/23/2011, 3:35 pm
Re: Skin-on-Frame: Alternative flotation material
Brian Nystrom -- 8/27/2011, 8:07 am
Re: Skin-on-Frame: Alternative flotation material *PIC*
Brian Nystrom -- 8/27/2011, 8:13 am
Re: Skin-on-Frame: Alternative flotation material
Bill Hamm -- 8/28/2011, 2:15 am
Re: Skin-on-Frame: Alternative flotation material
Brian Nystrom -- 8/28/2011, 8:30 am
Re: Skin-on-Frame: Alternative flotation material
Bill Hamm -- 8/29/2011, 2:04 am
Re: Skin-on-Frame: Alternative flotation material
Mike Savage -- 8/22/2011, 4:33 pm
Re: Skin-on-Frame: Alternative flotation material
Tony Ling -- 8/23/2011, 11:38 am
Re: Skin-on-Frame: Alternative flotation material *PIC*
peterchech -- 8/23/2011, 12:09 pm
Re: Skin-on-Frame: Alternative flotation material
Bill Hamm -- 8/23/2011, 1:40 pm
Re: Skin-on-Frame: Alternative flotation material
Sean D -- 8/23/2011, 2:15 pm
Re: Skin-on-Frame: Alternative flotation material
Bill Hamm -- 8/23/2011, 2:45 pm
Re: Skin-on-Frame: Alternative flotation material
peterchech -- 8/23/2011, 3:17 pm
Re: Skin-on-Frame: Alternative flotation material
Bill Hamm -- 8/23/2011, 3:27 pm
Re: Skin-on-Frame: Alternative flotation material
Sean D -- 8/23/2011, 1:49 pm
Re: Skin-on-Frame: Alternative flotation material
Tony Ling -- 8/23/2011, 2:13 pm
Re: Skin-on-Frame: Alternative flotation material
Will N To Go -- 8/23/2011, 3:50 pm
Re: Skin-on-Frame: Alternative flotation material
Mike Savage -- 8/24/2011, 8:09 am