Fleece/cotton fiberglass boat

Um... the whole point is that the fabric wets out, it becomes a hard shell and is waterproof

 

Dacron wets out OK with resin, but no relatively thin cotton/polyester etc fabric is going to give much in the way of stiffness and strength without the use of a thicker layer of structural reinforcement fibre, like glass, Kevlar or carbon fibre.

Certainly thin fabric wetted out with resin will get stiffer, but unless it's a structural type reinforcement there may well not be much strength in it.

 

I mentioned before that the initial layer was just a shell to build off and multiple layers would be required

 

Looks like a stubby sit on top kayak ...

 

Kenaf

A guy in india was talking burlap boats. You could also take a look at some new cheap sustainable composite materials. Their performance may not be as good as glass, but as you stated, you were mainly looking for a layer to form up over. Kenaf is a trendy sustainable composite material. The Kenaf plant comes to full maturity in a year and produces stiff fibers. The problem with cellulose fibers is that they are highly vulnerable to water absorption. Wood is cellulose, obviously. But kenaf, I believe produces bast fibers. In any case they would need to be sealed properly. Still, it looks promising. Good luck!!

 

Chicken Wire?

Sounds like you were using something akin to chicken wire..

 

Problem with that?

 

I take it you didn't actually read post #28

 

El Guero,

Yes that was me. Outside of a few people asking questions to the original Post I didn't think anyone was interested.

Sorry this took so long, somehow I got dropped off of about 3 pages of replies.

Marc

 

Chicken Wire

Not at all. Just wasn't sure what the material was exactly. The wire is stiff, light, usually honeycomb shaped for good cross sectional support, and reasonably inexpensive. Sounds like a winner!

 

The natural material to use with wire mesh is concrete.
From my personal preference, I would prefer no threads about concrete kayaks.

Wire mesh by itself generally has no cross section support, since it is so thin. To get good support you would need a very high tension in a straight wire. Mesh has no straight wires.

This is a very bad idea.

Cheap though, if you discount the amount of fairing you will have to do, unless you don't care about smoothness.

 

The fairing problem would seem tricky, unless by using forms you could somehow come out reasonably flat on the outside shell. perhaps he could run wire around forms transversely, apply an initial outer coating, and come back and braise in some longitudinal wires for support after it sets up. But what I don't understand is why there wouldn't be enough structural support using fiberglass alone with a mold if you are going to go to all that trouble.

 

I have used this technique on two boats, one a 16 ft kayak, and the other, the pod on a 20ft open trimaran. I used heavy calico ( cotton) in both cases

It works fine, but the downside is that during curing, the fiberglass warps the cotton, and doesn't retain the exact stretched shape. It becomes more concave, making a sunken effect.

If you planned for this effect, it is a good easy way to make a mould for glass, as the material is self fairing.