need help in building a small catamaran

Discussion in 'Multihulls' started by yoram, Nov 18, 2010.

  1. yoram
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    yoram Senior Member

    it is more folding to the back. i mean retractable on the same horizontal X line, retracting into themselves to the center of the boat
     
  2. Manfred.pech
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    Manfred.pech Senior Member

    Sorry, Yoram, can not remember to have seen something like this. If you are looking for floats I found an interesting (may be) adress for you. They sold the old boats for under a 100€, some for under 50. The racing kayaks and canoes are easy to change for trimaran outer hulls: http://members.ebay.de/ws/eBayISAPI.dll?ViewUserPage&userid=gelbemaus_de
     
  3. Fanie
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    Fanie Fanie

    Here we go again.

    Polyester doesn't work well with wood because it doesn't bond well with wood.

    I don't use wood - wood rot so I use polyester with other materials that gives excellent results. To say engineering properties are so poor compared to epoxy... wreckless statement. There are many many polyester boats - more than epoxy becuase of the finacial impact - that is many years old and they seem to do pretty well.
     
  4. michael pierzga
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    michael pierzga Senior Member

    Its poor on wood !!!!!! and for fillet and tape construction.
     
  5. yoram
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    yoram Senior Member

    What kind of other material do you use with polyester?
     
  6. yoram
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    yoram Senior Member

    Manfred, about the retractable amas, my idea is not that original. i am sure someone has already thought about it. i wonder why it is not done in trimarans, at least in the small ones? it is just to pull the amas in a strait line until they meet the center boat and the arms are collected into the the center boat. could you see any disadvantages to it?
     
  7. rayaldridge
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    rayaldridge Senior Member

    Yoram, do a search for the L-7 trimaran. This is an ingenious design that uses retractable floats.
     
  8. Fanie
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    Fanie Fanie

    Hi Yoram.

    I use a polyethilene foam because the bond is 100%, have a look at Sondor.co.za. I have made beams, hulls etc using this foam, and I will probably make the deck from it as well in a core foam. Once the fiberlglass cured on this foam, the foam acts like a big rubber mounting.

    Whatever you make in polyester as parts. do not glass the part in place. Design the part so that it has a foot where you can apply a sealer to, similar as soudal or dow corning one of those sealants, the bond is superior. Do not use silicone !

    I tested a 60mm x 100mm bond between two pieces of glass and it holds under 200kg of preying apart on the one side. They even bond car parts together with these sealants nowadays, Volvo is one.

    So what you cannot make in one part out of polyester, you glue into place.

    Always test before assuming !!!!
     
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  9. Manfred.pech
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    Manfred.pech Senior Member

    Sliding beams

    Do you mean something like this: http://www.lunadadesign.com/neo-21-sliding-beam-catamaran.html ?
     
  10. yoram
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    yoram Senior Member

    yes. like this.
    ok, so it is done in trimarans.
    in a few days i am going to start building a canoe. i have ordered epoxy from a local guy here. it is expansive. plywood, 4 liter epoxy and glass tape would be around 300 euro. a weekend in Amsterdam... but i am sure it is going to be enjoyable.
     
  11. yoram
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    yoram Senior Member

    yes. thanks. i looked it up and it is what i was asking about.
     
  12. Manfred.pech
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    Manfred.pech Senior Member

    New Boatbuilding Material

    Fanie can you please give us a link to your little Trimaran (?) you built with this materials?
     
  13. Fanie
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    Fanie Fanie

  14. rayaldridge
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    rayaldridge Senior Member

    Fanie, that is a truly ingenious little tri.
     
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  15. Fanie
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    Fanie Fanie

    No, not really. I wanted somethin to play around with and do some experiments. If those hulle were racing hulls and the sail the right size then I'm sure it would have been a different matter all together. I tell you guys that aft mast sail has huge potential and it operate so easy especially the furling and deploying compared to other sails.
     
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