Sailing Dinky centre board design

Discussion in 'Boat Design' started by Full Blown, Mar 30, 2011.

  1. Full Blown
    Joined: Mar 2011
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    Location: Scarborough Queensland

    Full Blown New Member

    Hi, out there in sail land. Iam a complete novice sailer and have just bought a lovely 11ft Frisco sailing dinky made of marine ply. But It has come with no centre board. Questions, this boat was advertized as a Frisco but I can not find any infomation on this style of boat. What type of wood would be best to make a new centre board. And for this type of boat (and maybe 11 ft is all we can work with) what depth should centre board protrude beneath my boat. Its width should be 235mm judgeing by the exit slot on bottom of hull. Looking forward to anyone helping me
     
  2. tom28571
    Joined: Dec 2001
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    Location: Oriental, NC

    tom28571 Senior Member

    Such a foil is not critical but we would need to know the sail area for an informed guess at the depth. With a slot length of 235mm, we are really thinking about a daggerboard and not a centerboard. Both are in the center but that is the convention for keeping things understandable.
     
  3. lewisboats
    Joined: Oct 2002
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    Location: Iowa

    lewisboats Obsessed Member

    This one sticks out about 1 metre below the hull and I use a 7.1 sq metre sail which works well. The board is about 300 mm wide by 24 mm thick at the maximum... laminated from 4 pieces of 6mm 5 ply plywood. The boat is a 12 ft planning scow. I have a Barnett Butterfly which has a smaller DB, about the same size as the one you might need. It is about 1.2 m long x 235 mm wide by 20-24 mm thick. That sail is about the same if a different style.

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  4. Full Blown
    Joined: Mar 2011
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    Location: Scarborough Queensland

    Full Blown New Member

    Center board design

    Hi guys, thanks for the advise. I am new to posting or answering threads. But here goes, Tom28571, The main sail area is 4mt high, 2mt across and 4.5mt diagonial (although sail on diagonial edge is rounded, battened, so i would have to add more). Now I am old school, so my measurements are height 13ft, wide 6ft-6inches and diagonial 14ft-6inches, adding extra for rounded edges I guess 42sq feet plus extra for rounded edges(8sq ft)maybe 50sq ft. The fore sails area is 9ft high 4ft-6inches wide and 10ft diagonal, this equals around 20sq ft. So all up ,I guess 70 Sq ft of sail area total or converted to metric 6sq mts maybe. Anyway Guys can you give me an idea about depth of the centre board or dagger board. Hey, how can I get to see an illastration of a dagger board. Is it shaped with a curve towards the back of the boat. Oh, the centre board opening inside the dinky is 300x20mm but narrows at the exit of the hull to 235x20mm with the 55mm taken of the bow end of centre board if you can understand my discription.
     
  5. Full Blown
    Joined: Mar 2011
    Posts: 4
    Likes: 0, Points: 0, Legacy Rep: 10
    Location: Scarborough Queensland

    Full Blown New Member

    Hi guys, thanks for the advise. I am new to posting or answering threads. But here goes, Tom28571, The main sail area is 4mt high, 2mt across and 4.5mt diagonial (although sail on diagonial edge is rounded, battened, so i would have to add more). Now I am old school, so my measurements are height 13ft, wide 6ft-6inches and diagonial 14ft-6inches, adding extra for rounded edges I guess 42sq feet plus extra for rounded edges(8sq ft)maybe 50sq ft. The fore sails area is 9ft high 4ft-6inches wide and 10ft diagonal, this equals around 20sq ft. So all up ,I guess 70 Sq ft of sail area total or converted to metric 6sq mts maybe. Anyway Guys can you give me an idea about depth of the centre board or dagger board. Hey, how can I get to see an illastration of a dagger board. Is it shaped with a curve towards the back of the boat. Oh, the centre board opening inside the dinky is 300x20mm but narrows at the exit of the hull to 235x20mm with the 55mm taken of the bow end of centre board if you can understand my discription.
     

  6. Full Blown
    Joined: Mar 2011
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    Location: Scarborough Queensland

    Full Blown New Member

    Hi again, hey friends I just googled daggerboards and up came a forum page debating them against eachother. Anyway, I came to realize that my boat has a dagger board. So, concidering my sail size can you recomend a size and design for me. Interestingly, one post I read mentioned a d/b with a curve aft at the tip, what is that in layman's language. Is this a shape curving forward towards the bow? Look forward to your suggestions.
     
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