folding daggerboards catamarans

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

  1. Racman
    Joined: Feb 2018
    Posts: 8
    Likes: 0, Points: 1
    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
    Posts: 1,620
    Likes: 51, Points: 48, Legacy Rep: 75
    Location: Florida

    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
    Posts: 8
    Likes: 0, Points: 1
    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
    Joined: Feb 2012
    Posts: 1,620
    Likes: 51, Points: 48, Legacy Rep: 75
    Location: Florida

    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
    Posts: 8
    Likes: 0, Points: 1
    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
    Joined: May 2009
    Posts: 16,679
    Likes: 349, Points: 93, Legacy Rep: 1362
    Location: Cocoa, Florida

    Doug Lord Flight Ready


  7. jorgepease
    Joined: Feb 2012
    Posts: 1,620
    Likes: 51, Points: 48, Legacy Rep: 75
    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 )
     
Loading...
Forum posts represent the experience, opinion, and view of individual users. Boat Design Net does not necessarily endorse nor share the view of each individual post.
When making potentially dangerous or financial decisions, always employ and consult appropriate professionals. Your circumstances or experience may be different.