Transom angle for outboard boats

Discussion in 'Boat Design' started by Raptor88, Mar 29, 2022.

  1. Raptor88
    Joined: Apr 2021
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    Location: Hawaii

    Raptor88 Junior Member

    One setting for my Tohatsu 6 HP outboard puts the transom angle at 15 degrees. I'm thinking building a boat with a 15 degree transom angle would be a good thing when reversing or for any waves that may hit the transom.

    Are there any negatives for a transom angle of 15 degrees as opposed to 12 degrees or less?
     
  2. fallguy
    Joined: Dec 2016
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    fallguy Senior Member

    so much depends on the boat design

    I built my transom at 14 degrees. You can always bump the engine out, but never back in without wedges...

    15 degrees is quite a lot
     
  3. messabout
    Joined: Jan 2006
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    Location: Lakeland Fl USA

    messabout Senior Member

    Most small outboards presume a 14 to 15 degree transom angle. The clamp brackets are configured so that the lower unit is positioned somewhere near the best normal angle of propulsion. Big outboards are a whole other deal. Most of them will have trim adjustment mechanisms. so that the transom angle is not a major factor in most cases. For the small motor use the manufacturers recommendation of 14 to 15 degrees. That is a handy angle because if you use a one on four bevel for transom tilt, you get an angle of 14.036 degrees which is close enough.
     
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  4. Raptor88
    Joined: Apr 2021
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    Location: Hawaii

    Raptor88 Junior Member

    Thanks for your input.
     
  5. Raptor88
    Joined: Apr 2021
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    Location: Hawaii

    Raptor88 Junior Member

    Sounds good. I'll go with 15 degrees for the transom for the boat I will be building. Thanks.
     
  6. philSweet
    Joined: May 2008
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    philSweet Senior Member

    The only real concern is the lift-out clearance in the raised condition. For short-shaft OBs, too much angle doesn't always get the foot entirely clear. But if it doesn't live year-round in salt water, this isn't a huge deal.
     

  7. Raptor88
    Joined: Apr 2021
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    Location: Hawaii

    Raptor88 Junior Member

    Very good point that I had not considered. I'll check that aspect out and decide. My boat will only be in the water while we're using it.
    Thanks!
     
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