Repair to a daggerboard

Discussion in 'Multihulls' started by abourgault, Feb 3, 2017.

  1. abourgault
    Joined: Jul 2014
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    Location: canada

    abourgault Junior Member

    Hi all,

    I have bought a beach catamaran that had a daggerboard in which a 5/16 hole has been drilled. The board protrude about 39 inches under the hull and the hole is at 10 inches under ther hull. The transverse location of the hole is at about the middle of the board. the maximum thickness of the profile is 1 inch.

    The daggerboard is foam cored, The reinforcement is mainly uni carbon fiber, about 1/4 inch thick on each side of the foam where the hole is.

    How would you repair that?

    Thanks for your help.

    AB
     
  2. PAR
    Joined: Nov 2003
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    Location: Eustis, FL

    PAR Yacht Designer/Builder

    Tape one side of the hole with packaging tape, then wet out the hole with straight epoxy. Next mix up a thickened batch, milled fibers and silica should be tough enough and fill the hole. When cured, remove the tape and cover both sides with fairing compound.
     
  3. abourgault
    Joined: Jul 2014
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    Location: canada

    abourgault Junior Member

    Thanks PAR. I was hoping that it would be that simple.

    AB
     
  4. waynemarlow
    Joined: Nov 2006
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    Location: UK

    waynemarlow Senior Member

    The hole is there to allow the board to be lifted by an amount in strong conditions and a pin put through to stop it at that point. Its a way of depowering the boat once the downhaul is full on, the mast completely facing the rear and a bit of travellor let out a little, if you are still over powered at that point, you start lifting the board. A lot of the racers have a piece of bungee attached to the top of the board running foward and that will lock the board off as well.
     
  5. abourgault
    Joined: Jul 2014
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    Location: canada

    abourgault Junior Member

    I understand what you are talking about but it's not the case here.
    The location of the hole would leave only 6 inches of board protruding under the hull.
    There's no gelcoat in the hole. It has been drilled afterward and the main reason is there's no such hole in the other daggerboard and I had another boat exactly like this one with no holes in the board.
     
  6. UpOnStands
    Joined: Nov 2015
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    Location: Sydney

    UpOnStands Senior Member

    I'd like to suggest one alteration.
    place the packing tape on one side but then use an exacto type knife to cut the hole's circumference into the tap and remove the center. fill with the thickened mix slightly proud of the surface, push it down and flush with a plastic flat edge, slap another piece of packing tape over it, go to the other and completely fill the hole etc etc
     
  7. PAR
    Joined: Nov 2003
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    Location: Eustis, FL

    PAR Yacht Designer/Builder

    I usually don't bother with the tape approuch, mostly because it's not very neat. I usually grind the outside with a shallow chamfer around the perimeter of the hole. Next I place a piece of light plywood (protected) over the hole, clamping as necessary. Then it's flipped and the hole filled slightly proud. The result is one side that needs little fairing. I mentioned the tape as it's the down and dirty way of getting it done.
     

  8. abourgault
    Joined: Jul 2014
    Posts: 22
    Likes: 1, Points: 3, Legacy Rep: 10
    Location: canada

    abourgault Junior Member

    Thanks every one for the help. I was hoping thast just filling the hole would be sufficient and from your comments that's what I will do.

    AB
     
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