GOP Home Build

Discussion in 'Boat Design' started by schultzfactor, Oct 25, 2013.

  1. schultzfactor
    Joined: Oct 2013
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    Location: Rotorua New Zealand

    schultzfactor Senior Member

    Power change

    I managed to get my hands on three 45 jp four stroke Hondas. With the motors now being mounted on each sponson, should I remove the pod in the centre of the tunnel?
     

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  2. Mr Efficiency
    Joined: Oct 2010
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    Mr Efficiency Senior Member

    Leave it there for the time being, imo. If your boat is inclined to squat, it may be of assistance. This is going to be interesting !
     
  3. schultzfactor
    Joined: Oct 2013
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    Location: Rotorua New Zealand

    schultzfactor Senior Member

    Transom Thickness

    I have fibreglassed the two transoms into the Pods. I am not sure how thick i should go with them. Currently they are 10mm Ply/ 400 GSM X 2 Layers /10mm Ply/ 400 GSM. I am also not sure whether to just bolt them to the transom, or fibreglass them??
     

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  4. philSweet
    Joined: May 2008
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    Location: Beaufort, SC and H'ville, NC

    philSweet Senior Member

    Not thick enough. I don't know what the minimum would be for your setup, but I know what I would use. 40mm of hardwood marine ply with aluminum plates on both sides. The plates should be 5/8 as thick as the mounting bolt diameter. On the outside, it extends about 1 thickness past the motor mount profile. On the inside, about 1 bolt diameter past the bolt holes. You should be able to rip/wring the motor off its bracket without damaging the boat. I've managed to do that twice on the water, plus the gf knocked down a telephone pole backing up in a parking lot, plus a Honda Civic rearended me. Honda was totalled, trailer was torn apart, boat was fine.
     
  5. SamSam
    Joined: Feb 2005
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    Location: Coastal Georgia

    SamSam Senior Member

    I can't really tell what that is or how it's supposed to work, but if two motors somehow hook unto it, it looks pretty minimal/flimsy. Where is the 20mm of ply located? If the two slots are the 'transoms', what is to stop those transoms from coming apart from the rest of the thing at the corners....just some csm?
     
  6. schultzfactor
    Joined: Oct 2013
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    Location: Rotorua New Zealand

    schultzfactor Senior Member

    Pods

    image.jpg Great. The whole pod still has to be overlayed with fibreglass and I'm not sure whether to fillet and fibreglass the corners or Insert aluminium brackets? Yes the slots are where the motors go. They weren't designed for outboards as I was going to have a single outboard but managed to get two four strokes at a good price. They are pretty small motors and only 100kga each. I'm just trying to beef up what were boarding steps into pods now. 40 mm sounds good. I like the idea of breaking power poles! Please don't be mistaken, this is not near the final product.
     
  7. schultzfactor
    Joined: Oct 2013
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    Location: Rotorua New Zealand

    schultzfactor Senior Member

    Bullbars

    Hey PhilSweet, sounds like you need some Aussie Roo Bars on the back of your trailer!
     
  8. SamSam
    Joined: Feb 2005
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    Location: Coastal Georgia

    SamSam Senior Member

    Yes, you'll need a ladder to get back in that with such high sides.

    Once you start using the boat, and until you know if the transoms are strong enough, I would seriously consider tying some ropes to the motors so they don't irretrievably sink should they break off. That would also drastically reduce their time underwater if they do, which is for the better.
     
  9. schultzfactor
    Joined: Oct 2013
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    Location: Rotorua New Zealand

    schultzfactor Senior Member

    I've designed some life jackets for the motors just in case.
     
  10. SamSam
    Joined: Feb 2005
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    Location: Coastal Georgia

    SamSam Senior Member

    OK, but keep in mind that a 200 pound motor won't float the same as a 200 pound person. A human is made from a lot of water and will have a lot of neutral buoyancy, not to mention the positive buoyancy of all the fat in a lardass, so you only have to compensate for a small portion. The whole motor is negative buoyancy so you have to compensate for the whole thing.
     
  11. schultzfactor
    Joined: Oct 2013
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    schultzfactor Senior Member

    Got it, maybe have to add some deplorable airbags!
     
  12. SamSam
    Joined: Feb 2005
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    Location: Coastal Georgia

    SamSam Senior Member

    LOL! I know what you're saying, and I can't think of the word either, but deplorable ain't it.

     
  13. SamSam
    Joined: Feb 2005
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    Location: Coastal Georgia

    SamSam Senior Member

    I think it's 'deployable'.
     
  14. schultzfactor
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    Location: Rotorua New Zealand

    schultzfactor Senior Member

    Ha

    Ha yeah Deployable, bloody autocorrect!!
     

  15. Mr Efficiency
    Joined: Oct 2010
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    Mr Efficiency Senior Member

    Because the transoms on such boats are small, there isn't much width of unsupported span, so for test purposes you needn't go overboard with the lay-up, with 45hp motors. It is going to be a red-letter day when this thing has its moment of truth ! Hopefully a happy event.
     
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