What is the best inboard shatf angle for this hull?

Discussion in 'Boat Design' started by OCB, Nov 9, 2018.

  1. OCB
    Joined: Dec 2015
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    Location: USA

    OCB Senior Member

    I'm posting this thread to get input on a new idea for correcting inboard shaft angle. I want to get some ideas from BDF of the best angle for this hull #309. I want to understand better the design benefits that mite be gained from this type of changes to shaft angles.
    This machinery drawing of hull #309 is being use as a example of a hull with both cavitation and vibration problems.
    I was not able to continue to work with BDF member that I started this project with. I want to thank member jhonect VERY MUCH for all his help, information and drawings you did for me. Your willingness to share your vast knowledge with me will not be forgotten.
    The cad drawing with the joint in the shaft was done show my new design.


    Attached Files:

  2. JSL
    Joined: Nov 2012
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    Location: Delta BC

    JSL Senior Member

    A drawing and specs of the boat might help. Is it a 70' x 19' aluminum passenger vessel?
    I don't think the angle x drive will work.. One feature: the prop thrust will push everything to misalignment. And, if a passenger vessel it will be USCG inspected and that could be a challenge.
    For a conventional installation, check engine installation angle against the engine specs and allow at least 5 degrees for running trim.
    Last edited: Nov 9, 2018
  3. gonzo
    Joined: Aug 2002
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    gonzo Senior Member

    It seems like a really large angle. You will probably have to modify the oil pan and oil pump pickup.

  4. OCB
    Joined: Dec 2015
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    Location: USA

    OCB Senior Member

    Thank you guys very much for the great input on this design.
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