16 ft foam catamaran

Discussion in 'Boat Design' started by Keenan, Aug 10, 2011.

  1. Keenan
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    Keenan Junior Member

    Hi,

    I'm building a 16 foot catamaran and would like the hulls to be made of foam. I was wondering if anyone might know about how much I'll need, and where to find the foam. I also heard that you can use stirafoam in the hull so that you don't have to use as much of the high density foam, is this true? Thanks!

    Keenan
     
  2. Richard Woods
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    Richard Woods Woods Designs

    Do you mean solid foam that you cut to shape and glass over like making a surfboard??

    Or pvc (or maybe polyurethene) foam sandwich panels ??

    Styrofoam dissolves in polyester resin so you need to use epoxy. It also dissolves in gasoline so you cannot use it unprotected.

    Whatever way you build you need to think how to attach the beams to the hulls, and if it is a sailing boat, the chainplates.

    Most small one-off beach cats are built in 3/16in plywood for speed, lightweight and low cost

    Richard Woods of Woods Designs

    www.sailingcatamarans.com
     
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  3. Keenan
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    Keenan Junior Member

    Do you by chance know about how much the cost would be if it was made out if plywood? Really I am just looking for the cheapest way to build it, without losing any performance level, which is why I don't want to build a PVC catamaran.

    Keenan
     
  4. FMS
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    FMS Senior Member

  5. Keenan
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    Keenan Junior Member

    Would I need multiple layers of fiberglass?
     
  6. Richard Woods
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    Richard Woods Woods Designs

    You'd need about 6 sheets of 3/16in ply (WBP, doesn't need to be marine grade). No structural need to sheath the hull with glass

    So 1 gal epoxy is about enough

    Look at my Pixie, Quattro 14 and Quattro 16 beach cats for ideas.

    Richard Woods of Woods Designs

    www.sailingcatamarans.com
     
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  7. Keenan
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    Keenan Junior Member

    Epoxy would be enough to keep the water out of the hulls? I wouldn't need to fiberglass them?
     

  8. Richard Woods
    Joined: Jun 2006
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    Richard Woods Woods Designs

    That's right. In part because I am assuming you would not be leaving the boat in the water all the time. If you are then it is sensible to glass sheath the below WL area.

    BTW, if you want to meet up you might like to know that I will be at the Port Townsend Wooden Boat festival Sept 8-11th

    Richard Woods of Woods Designs

    www.sailingcatamarans.com
     
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