Simple foam proa

The hull design appears as good a start as you could hope for, nothing looks too 'way out'. Its such a simple shape, you could certainly easily do the top section in ply, and save your self a lot of hassle while getting some useful storage.

I don't call the crab-claw unproven and I cant see where I said that. It worked great for the islanders who had to use the materials at hand, with the boats they built. Unless you are going to hammer your hull out a big tree to build a replica - why would you suffer from their limitations ?

I cant stress too much how much less effort,cost and hassle doing a proven design out of quality materials would be, but often it takes years of experimentation to convince some people ( like me)

 

Actually it was JRD who said Crab Claw is un proven at the end of this post.

Why I would suffer from the islanders limitations? Because I have about as much money to put into this project as they have . I was actually considering going out to the woods some day and cutting me a nice mast

I found a nice site with some step-by-step plywood catamaran building pictures: http://www.gust.ax/gallery/f12/

 

hi Luovahulluus

The build in the catamaran building link you posted was exactly what I hoped you would consider.

I think your build methods can probably be simpler again than the cat. At a glance your hull shape looks pretty good really. If you are looking for least cost and a quick simple build, then I would consider making it a flat bottom, its so narrow at the waterline that you wont get much slamming in waves and it will float higher. The 200kg displacement should be close, but dont forget to add a bit to your weight as you can easily end up with 5-10kg of sailing gear each once its wet. If you are careful the rigged weight of the boat should be less than 70kg.

The point I was trying to get across about the rig is that if you are starting from bare parts without an exact design, then its unproven. It all depends on your level of experience and practical abilities whether you should go down the track of developing it for yourself. Its often possible to purchase second hand rigging components and small sails for peanuts.

 

Hi JRD

Now I see your point about the rigging. That's exactly why I was looking for plans/instructions on how to make one.

The 200kg of displacement is for main hull only. The ama will get me another 25 to 55kg. Ofcourse if/when I'm flying it the whole weight will be on the main hull.

I'm not really after a simple build, I'm pretty good with my hands. The big limitations for me are money, space and the lack of tools and machines.

I found someone else using Finnfoam for a boat. He also did some compression tests.