concrete in keel

Discussion in 'Boatbuilding' started by Lexluthor, Jul 18, 2010.

  1. Lexluthor
    Joined: Jul 2010
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    Lexluthor Junior Member

    Hi all,

    I've purchased a steel ketch which i plan to strip completely and make a new interior, the long keel is filled with scrap iron, steel punchings and concrete,
    I'm thinking of chiseling out the concrete & scrap iron and replace that with lead and a layer of poured in expoxy.

    Anyone has any thoughts about such a project, should i weigh every bit of concrete and iron and put in the same weight of lead?

    with kind regards,

  2. peter radclyffe
    Joined: Mar 2009
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    peter radclyffe Senior Member

    kryptonite would be denser
  3. Lexluthor
    Joined: Jul 2010
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    Lexluthor Junior Member

    unfortunately i'm using my limited supply of cryptonite for other purposes ;)
  4. Lurvio
    Joined: Jul 2009
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    Lurvio Mad scientist

    Let the Mythbusters remove the concrete. :)

    The serious part: If the concrete is dry and doing its job, why remove it?

  5. Petros
    Joined: Oct 2007
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    Petros Senior Member

    Ditto Lurvio's thought: why remove it? Especially if you are just putting the same amount of weight back.

    I have seen concrete used on older designs, it is inexpensive but not as dense as metal, especially lead, so the keel has to be larger. It sounds like the concrete is there to hold the scrap metal in place. If you wanted to add or change the amount of ballast, that would be a reason to change it. IF you are worried about it corroding or chipping out, clean it up in place and seal it with epoxy.

  6. gonzo
    Joined: Aug 2002
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    gonzo Senior Member

    I think you already have another thread on the same subject. The structural stresses will increase with a concentrated ballast further below. It may end up in hull and rig damage. Also, it will make the boat more lively.
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