Beam design for a demountable catamaran

Discussion in 'Multihulls' started by guzzis3, Dec 21, 2016.

  1. basil
    Joined: Apr 2005
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    Location: aUSTRALIA

    basil Senior Member

    Simplist and best catamaran folding system yet. Yeah kinow Richard Woods has the same thing but here the trailer is the key

    http://www.s-boat.com.au/
     
  2. guzzis3
    Joined: Nov 2009
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    Location: Brisbane

    guzzis3 Senior Member

    Well on sango the trailer is the key aswell.

    If I wanted a FOLDING cat I'd get a sango or wizard. I was just pondering a way to overcome the hull rotation issues.

    I suppose I'm missing something important, but many other people place more emphasis on performance than I do. I want a boat with a level of comfort I can be happy with, a boat that's easy (ish) to live with and that's pleasant to sail. I've spoken to Mr Surtees at length and I find him a very pleasant gentleman, but his boat does not appeal to me. To each their own.
     
  3. UpOnStands
    Joined: Nov 2015
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    UpOnStands Senior Member

    for Guzzis3, for "fair" sailing, what would be reasonable freeboard, draft, bridge deck clearance?
     
  4. guzzis3
    Joined: Nov 2009
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    guzzis3 Senior Member

    That's a hard question to answer concisely. To me it's a boat that makes decent progress across a days passage, sails ok on all points, has good manners and isn't too wet or harsh.

    There is nothing wrong with a fast boat but it often comes at a cost, and not just in the buying. If your sailing on a knife edge that's exhausting. If it rides hard and pounds in a seaway that's painful. Most of all if you've sacrificed your accommodations that's uncomfortable.

    I watch the australian market pretty closely. Most boats take a long time to sell because most owners are optimistic about what the market will bear, but from what I see (it's hard to say definitively) boats with limited accommodations are a niche. There are the racers that love that stuff but a decent cabin seems to command a decent premium in sale price. I suspect there is a broader market for a decent sail boat with good accommodation.
     
  5. Beamreach
    Joined: Oct 2016
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    Location: Ontario Canada

    Beamreach Junior Member

    "The idea is:

    A complex trailer with swing wings rather than sliding beams to spread the hulls, and a central section which raises on a parallelogram using the tailer winch. Swing wings mean no binding, the arms work in your favor about the pivots rather than the size of the hulls working against you to bind up."

    Taking Guzzi's idea for making a Swingwing trailer to use on R Woods 24' Eagle.
    I'm wondering what materials for building the hinges would stand up to use.
    The hulls are 750 lbs (341 kilo) ,I 'm not good with metal welding,I am good with glass ,or hard wood . Would this be a good use of Carbon/ wood ?Have a quite bit of carbon uni unused.
    Suppose a metal hinge is ideal ,would prefer a composite glass one as I can build that way....
     
  6. guzzis3
    Joined: Nov 2009
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    guzzis3 Senior Member

    Heavy duty galvanised gate hinges are the simplest solution, remember that 350 kg is distributed over 2 pairs of hinges.

    I'm curious where you got that figure. The total empty weight is quoted as 600 kg. Are you including cruising fitout ?

    Anyway you could get pivots fabricated, with or without radial roller bearings. Bushes would be fine. It's a trivial problem for any metal fabricator.
     

  7. Beamreach
    Joined: Oct 2016
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    Location: Ontario Canada

    Beamreach Junior Member

    Empty displacement for Eagle 24 =650 kilo.
    True ,hulls will be less ,I just divided by two ,so there can be stuff in hulls .
     
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