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Re: Material: breaking hip braces
By:Mike and Rikki
Date: 3/23/2003, 3:44 pm
In Response To: Material: breaking hip braces (LeeG)

Lee

It would have cool if you were along, too. Hell, everybody along would have made for one helluva great paddlefest, we surely had enough wine for everyone!
:)

: just curious,,,reading through Mike and sings fabulous adventure in Santa
: Cruz island (am I jealous? yes very) and the misc. damange to one of the
: boats got me to thinking about breaking hip braces,,ie. what's a
: reasonable method of attachment and construction. Necky boat had these

That's a real good question. I'd like to refer to what I consider the bible in yak construction: my worn-out, stained and dog-eared copy of Nick's book, page 150-152. Nick discusses an effect where a hard attachment point item such as a bulkhead, or in Sage's case, a hip brace, can contribute to a hull failure. In Sage's case he has minicell foam bulkheads for the give that they provide in case of impact with rocks for that immediate area (which the rock impacts weren't even close to) and only two area where solid wood was attached which were for his hip braces (which of course suffered nearly direct impact with the rocks).

I was filing and sanding a block of minicell foam for my seat back and wasd thnking to remove the cheek plates in favor of two long , fitted foam pieces of minicell (the stiff stuff). My thoughts are that
1. this allows me a softer surface to brace against
2. provides additional buoyancy units in the case of compartment breaches (okay, I've been thinking about the effects of a white shark's tentative nibble on the yak's hull while being way the hell offshore. Sure would hate to swim like a seal in my black seal-like neoprene all the way back knowing a white is in the same area)
3. removes some of the cockpit volume in the event of being filled with water (likewise, the thick, customized foam back rest and thigh braces, and the future foot rests for my yak which exist on Rikki's yak now).

: huge swaths of unidirectional glass for the hip bracing,,other boats have
: suspended attachments for back bands with the bracing a function of
: minicell,,etc. For folks that have been in coastal conditions with your
: strip and s&g boats what have you found has been sufficient /insufficient?

Well, I over-glassed my first yak till I learned about what was enough however, I've thought long and hard about this issue in the other yaks and glassed the living hell out of hard attachment points. For the second yak, I actually epoxied in some 8 inch wide luan ply on the inside of the hull where the bulkheads were then installed. The idea was that the load would be spread over a wider area then the immediate area around the bulkhead. Still, for cheek plates, the only function they now serve for me at this time is a place to run lock cables.
I have removed and fitted the back bands (two) to a friends double, Rikki and I prefer fixed minicell backrests, so there's no need to keep the hard cheek plates.

: I know it's risky to draw generalities from a few specifics but what the
: heck. The consumer product safety council isn't dropping these things from
: buildings or sending them into surf with funny dummies so it's us dummies
: with the data.

It's a good thing that the goverment isn't involved. I'd hate to have that checkerboard paint job and all those sensors stuck into places that I'd rather not get into.

I'll post images and an evaluation report when I get time to go paddle.

Messages In This Thread

Material: breaking hip braces
LeeG -- 3/22/2003, 10:42 am
Re: Material: breaking hip braces
Mike and Rikki -- 3/23/2003, 3:44 pm