folding daggerboards catamarans

Discussion in 'Fiberglass and Composite Boat Building' started by Racman, Mar 7, 2018.

  1. Racman
    Joined: Feb 2018
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    Location: Perth W.A.

    Racman Junior Member

    HI all just a thought regarding design
    Why not mini keels and folding daggerboards?
    Would this not offer the best of both eg protected rudders but good windward preformance?


    I have no design or boat building experience,have been a keen sailing Farr owner for 20 years.I have seen this idea in the tralier sailer area.As I am plaining to build a cat in the next year thought this could work . very happy for your input guys.
     
  2. jorgepease
    Joined: Feb 2012
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    jorgepease Senior Member

    If I were the devils advocate,
    I would consider those slots fouling for one
    I would wonder what the benefit compared to the drag of a dagger combined with a mini keel as opposed to just a mini keel and kick-up rudder say...

    That said, I am going with a single, pivoted, stayed, center mounted board (off bridge deck) for my cat build. I'm interested to hear what others say about that folding dagger as well
     
  3. Racman
    Joined: Feb 2018
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    Location: Perth W.A.

    Racman Junior Member

    Yes Jorge
    fouling could be a problem if left on a mooring for a long time with no useage. But that said there are quite a few mono out there with droping center keels.
    but the advantage's that i see, is the extra bite or pivot point gained when trying to get maximum pointing. more focused center of resisitance. but thats just a guess.
    Plus no case taking up space inside.
    please tell me more about your center mounted board . Its sounds like a idea that could get legs.
     
  4. jorgepease
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    jorgepease Senior Member

    My idea is not original and it has it's drawbacks as well. Like a keel mounted board, it kicks up when you hit something and no interior space lost.

    In my case though, it's not in the water all the time, I will venture a guess that I might use it 10-20 percent of the time. So for that 80-90 percent of the time, I don't have that extra drag or other drawbacks such as fouling and I will only have a draft of 20-24 inches.

    Pic is worth a 1000 words )
    cb.jpg
     
  5. Racman
    Joined: Feb 2018
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    Location: Perth W.A.

    Racman Junior Member

    Jorge thank you for your input ,this looks very interesting I have not seen anything like it before. When folded it would look fine, not much chance of fouling.
    so what the draw backs? Just by the way I was reading one of your coments on a tread regarding thin stick on lining , but can find it again can you help there.
    By the way I could well use this folding design , great drawing to.
     
  6. Doug Lord
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    Doug Lord Flight Ready


  7. jorgepease
    Joined: Feb 2012
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    Location: Florida

    jorgepease Senior Member

    Ventilation, trapping air in waves... It's been suggested that a small plate below waterline might help with that and it might be possible to tilt the board forward slightly without changing the longitudinal pivot point. I want to be fast but I am not racing and most of my sailing will be trade winds. So I compromise slightly in one area, gain it back in another, a game of give and take, expectations of what I am most likely going to be doing with that boat, I feel comfortable about it and willing to gamble because I seriously doubt it's going to affect me negatively and I love the safety factor )
     
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