How would you fair this keel

Discussion in 'Boatbuilding' started by Darce, Sep 3, 2009.

  1. Darce
    Joined: Dec 2008
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    Darce Junior Member

    The original keel was apparantly knocked off after a storm drove her off the mooring and replaced with what you see here. I'm not too happy with the step left over from the original keel and wouldn't mind fairing it.

    Question is, with what?
     

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  2. daiquiri
    Joined: May 2004
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    Location: Italy (Garda Lake) and Croatia (Istria)

    daiquiri Engineering and Design

    Do you mind if I ask a you question first?
    It looks like the new keel has both the smaller chord and the smaller thickness than the previous one. Is this a decision taken on basis of hydrodynamic and structural calcs performed by a competent N.A./engineer, or ...?
     
  3. Darce
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    Darce Junior Member

    I doubt that very much.

    At a guess I'd say he was a welder. It's a steel plate with a bulb (hidden by the grass)
     
  4. daiquiri
    Joined: May 2004
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    Location: Italy (Garda Lake) and Croatia (Istria)

    daiquiri Engineering and Design

    That really upsets me, particularly the fact that a bulb was mounted on a thinner keel than the original one. And the original one has fallen off, as you said.
    If it was my boat I wouldn't just fair it. I would rather redo that job from the scratch, with proper scantlings done first.
     
  5. Darce
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    Darce Junior Member

    You're right. But that would be a job for next season. For now, I'm curious to see if there is something better than the 'automotive filler' I was recommended by some dingbat in another forum
     
  6. PAR
    Joined: Nov 2003
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    PAR Yacht Designer/Builder

    Did Mik tell you to hit it with some auto bog and call it a day? Tell the truth now.

    You're right it's putting the U in ugly, but the surface is "proud" not hollow, making for a difficult fairing situation. Ideally, the offending fair body potions of the previous keel should be cut off, the laminate replaced with similar thickness material and then faired for a smooth transition to the new appendage. Of course this is a lot of work for little gain. The protrusions will not hurt the performance of the yacht that badly, so leaving it as is wouldn't be so bad.

    You should talk to the chap that doing this job. Try to find out how much difference between the two keels there actually is. The fin on there now looks to be from a yacht half the volume of this one.
     
  7. Darce
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    Darce Junior Member

    Par, it was bad enough getting caught out mentioning GRP on 'that' forum... asking advice there for this problem would be the end of me.

    Cor, don't tell 'em I'm here :)
     

  8. PAR
    Joined: Nov 2003
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    Location: Eustis, FL

    PAR Yacht Designer/Builder

    Damn, leverage, I love it . . .
     
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