Mold material

I searched a lot of threads and I couldn't find what I was looking for so here goes:

I want to make a fiberglass deck for the main hull of my homebuilt trimaran. The main hull is 20' LOA with a 2' beam throughout the middle 1/3 with tapered bow & aft sections. The fiberglass deck will be in the shape of a conic section, sliced in two. Dimensions: 12' long, 0 to 24" in width and 0 - 20" in height.

I plan on making a male mold then fiberglassing that, but I can't think of what to make the mold out of. I thought about the 2" pink foam insulation sheets, gluing then together then shaping them, but I am not sure if this would be the easiest.

Any thoughts or suggestions as to what would be an easier material to make this mold out of.

 

Hi:
Try this and ad 5-6 foam ribs for stability, fast and cheaper than a solid foam,I hope this helps you... www.MyAluminumKayak.com

 

Wow, I never thought of that. Thanks, now I just have to figure out how to bend it into this shape with the dimensions that I need. Any tips?

 

Sorry, delete last post. I just figured it out.

 

" I thought about the 2" pink foam insulation sheets,"

Styrene - Its the stuff that makes fiberglass resin stink, melts styrofoam. IE that pink insulation. Been there, done that, made one heck of a mess when all the core turned to goo on us.

-jim lee