Lifting strakes on straight bottom 38'

Discussion in 'Powerboats' started by ICBlowboaters, Feb 24, 2019.

  1. ICBlowboaters
    Joined: May 2014
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    ICBlowboaters Junior Member

    On heavy old cigs the lifting strakes are shorter than other boats of the same era/size.
    From the edge of the transom, to the end of the inner lifting strake, it is 10ft on the scarabs. On the top gun, it was 14ft. One hull measures 37'7", other measures 37'6", but the scarab has 4ft more lifting strake.

    The Scarab runs much less "wet" and faster .
    The Cig seems to fall on and off the lifting strakes and for the most part once settled down the water breaks at the helm.
    Am I understanding the function of the lifting strakes correctly? (they help lift the boat)
    My thinking is would lengthening the strakes on the Cig. help keep the bow up? (increase speed)

    Cig:


    Scarab:

     
  2. gonzo
    Joined: Aug 2002
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    gonzo Senior Member

    Lifting strakes also decrease the wetted surface, which in turn decreases resistance.
     
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  3. Mr Efficiency
    Joined: Oct 2010
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    Mr Efficiency Senior Member

    It would not be hugely difficult to modify the length of them, you could glue on some wooden extensions, and if they don't help, just grind/sand them off. Might firm the ride up a little. Possibly create some more turbulence into your props.
     
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  4. gonzo
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    gonzo Senior Member

    A problem with strakes that run all the way to the stern is ventilation. If they are not placed properly they can act like a tunnel that carries air under the hull into the propellers.
     

  5. ICBlowboaters
    Joined: May 2014
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    ICBlowboaters Junior Member

    That makes sense. Boats that have the strakes all the way back also get a little squirrly at higher speeds.
    I was thinking of extending them about 4' not all the way back so there would still be 10' to the transom. They terminate at the helm [​IMG]
     
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