Uplifting Experience (remedying stern squatting while on plane)

Discussion in 'Boat Design' started by grady, Oct 19, 2011.

  1. grady
    Joined: Oct 2006
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    Location: Scituate, Ma

    grady Novice

  2. keysdisease
    Joined: Mar 2006
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    Location: South Florida USA

    keysdisease Senior Member

    Interesting piece of history you linked to. I actually sold marinium hardware to RAJ when they started up and later to Blackfin when they were in Port Everglades.

    I am familiar with the Blackfins and I believe you will find that the tabs are " pocket mounted" and of a very long chord (fore to aft dimension) because of the limited transon space taken up by the prop tunnels. This is because the boat needed more tab than the transom allowed for with standard chord tabs.

    There are trim tab "tricks" to increase lift / area but I would need more details.

    As you mentioned, these hulls were not originally designed for the power / weight you are considering.

    I have found that as vessels age the seem to acquire additional equipment which all too often ends up in the aft end. This coupled with a re power of engines with additional weight combines to make a real challenge for proper trim.

    Steve
     
  3. grady
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    grady Novice

    Hey Steve, Thanks for the reply. These Blackfins have a conventional bottom that's to say no prop tunnels. Pretty cool that you were involved with them back then.
     
  4. keysdisease
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    keysdisease Senior Member

    Then put much larger tabs on them then are currently installed. Maybe go for 48 x 12 which are the smallest of the dual ram configuration tabs from Bennett. All you will need is the tabs with hinges, one additional ram per tab and a couple of Tee fittings and some tubing. You can re use the existing ram (if its a standard Bennett Ram) and just tee into the existing tubing. The system is self bleeding too so when finished installing just run the tabs up and down a few times.

    The switch, wiring, pump all remain same and are quite capable of pushing dual ram 48 x 12 tabs.

    Put a swim platform on and you won't even know they are there.

    Steve
     

  5. grady
    Joined: Oct 2006
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    Location: Scituate, Ma

    grady Novice

    The boat I looking at has recessed tabs and with some rework on the bottom I'm sure its doable. And I have heard they do help. Some of the smaller boats have transom mounted tabs and do hide bigger ones under a swim platform.


    Thanks for your continued interest and help.
     
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