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Re: Skin-on-Frame: frame
By:Bill Hamm
Date: 3/23/2009, 12:26 am
In Response To: Re: Skin-on-Frame: frame (Mike Bielski)

: It sounds like it should be a good fit from the dimensions. I ran my deck
: stringers to the beam ahead of the foot rest like you did because I was
: worried about having room for my feet, but as it ends up it's more
: comfortable to paddle with my toes pretty pointed, and it's nice to be
: able to put my toes on top of the beam for "leverage" (but
: really just to help keep me locked in even more) when I'm rolling. I guess
: the bottom line is that I didn't really need to run it up there, but it
: was my first, and definitely not last, boat, so there are a LOT of things
: I'd do differently. You'll be able to tell when you saran wrap it if your
: feet will fit the way you want or not and if you need to adjust the masik
: height, but I didn't figure out my foot issue until I'd paddled it for a
: while with the final skin on.

: As for coatings- I did a ton of research into coatings and fabrics, and I
: think that there are two guidelines you should follow when you pick, no
: matter what your other criteria. First- will the coating stick to the
: fabric, and second- will the fabric stretch more than the coating.

: Not all varnishes or paints will stick to polyester or nylon, and if the
: coating doesn't stick, it will eventually delaminate. If the skin is more
: flexible than the coating, the coating will relieve the stress by
: cracking. In either case, you can switch skin materials to a different
: fabric/coating combination that will work well together, or you can just
: enjoy it as long as it works for you and then reskin it when it fails.
: Reskinning gives you a chance to make sure your frame's still o.k. or to
: make changes, so it's not a completely heinous thing.

: In general- canvas is the least stretchy and pretty much anything will stick
: to it, polyester is moderately stretchy, but many products intended for
: use on wood won't stick to it, and nylon is very stretchy, and again not
: all products will stick to it or be as flexible. Depending on the specific
: fabric you're using, nylon stretches up to 300%, which is why it's so good
: at puncture resistance. The trouble with using Zar on nylon is that Zar is
: designed to work on wood, and the maximum possible seasonal movement in a
: piece of red oak is 2.5%.

: The only common coatings that are a match for nylon's stretch on paper are
: Corey's goop and Coelan Marine Coating. Coelan was actually designed for
: use on flexible fabrics, and flexes 300%. It's one-part and goes on like
: any paint. I've only done test samples, but I'll use it on my next SOF.
: I've used Corey's goop, and it's tough. It's tricky to put on so that it
: looks good, especially for a first timer, but it will still be tough even
: if it's ugly (like mine). Just a word of advice on the Corey goop- I am
: very fussy. The people I know who used goop on their boat and had it turn
: out great the first time were not too fussy. Extrapolate what you will,
: but the boats look about the same from 5' away. I don't know what the
: specifics are on its flex, but it's pretty good, and is intended to be
: used as a SOF coating.

: But- don't take my word for it. Call up the manufacturers of the coatings and
: ask them. Things are changing all of the time and they'll know best what
: their stuff can and cannot do.

: m

: (BTW- I've only used Zar and Minwax Helmsman on wood, and only once each, but
: I liked the Helmsman better.)

Hi Mike,

Btw, just to throw a wrench into the works , there is another alternative, don't use nylon and instead use dacron with it's much lower stretch and since dacron isn't nearly as tear resistant, cover the dacron with a very light layer of fiberglass/epoxy.

Btw, I've now done several boats done this way, works very well.

Bill H.

Messages In This Thread

Skin-on-Frame: frame *Pic*
Clayton Plunkett -- 3/21/2009, 5:14 pm
Re: Skin-on-Frame: frame
Mike Bielski -- 3/21/2009, 6:00 pm
Re: Skin-on-Frame: frame
Clayton Plunkett -- 3/21/2009, 8:48 pm
Re: Skin-on-Frame: frame
FrankP -- 3/23/2009, 3:33 pm
Re: Skin-on-Frame: frame
Mike Bielski -- 3/21/2009, 10:57 pm
Re: Skin-on-Frame: frame
Bill Hamm -- 3/23/2009, 12:26 am
Re: Skin-on-Frame: frame
Daniel from sweden -- 3/22/2009, 3:54 am
Re: Skin-on-Frame: frame
Mike Bielski -- 3/22/2009, 2:08 pm
Re: Skin-on-Frame: frame *LINK*
Daniel from sweden -- 3/22/2009, 3:59 pm
Re: Skin-on-Frame: frame
Mike Savage -- 3/22/2009, 7:47 am
Re: Skin-on-Frame: frame
Clayton Plunkett -- 3/21/2009, 11:14 pm