Mashup Trimaran (continued)

Discussion in 'Multihulls' started by Bigfork, Feb 17, 2021.

  1. peterAustralia
    Joined: Mar 2006
    Posts: 379
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    Location: Melbourne Australia

    peterAustralia Senior Member

    Yes, just use bathroom scales, add the weights. The exact same method is used to weigh light aircraft (heavy aircraft too I believe). They put a bathroom scale under each wheel and add up. Have seen youtube videos of this for experimental planes and they want to check the weight after construction is completed. As to beam thickness, my guess would be 4 inches or so,,, but would have to do some maths,,,,, maybe give me a short time and I can give it a go
  2. Bigfork
    Joined: Dec 2009
    Posts: 66
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    Location: Montana, USA

    Bigfork Junior Member

    Greetings wise people!
    Pictures are of the aft box beam, minus the closing layer, and upside down.
    Also need to install blocking for hinges/fixatives to main hull aft mount.
    In boat profile drawing you can see the beam colored black.
    Questions for the powers that be:
    1. Do i put a wee fillet on each of the web sections or just epoxy em in place?
    2. Do i paint the raw interior w an epoxy coating before closing off?
    (If the section is deemed too weak for the task, i can incorporate water stays. I think a rear facing aero foil section would also help to strongback the beam.)
    92D8818F-9497-46A3-AC4D-885BA7885DB6.jpeg 8D7BC293-68F0-4225-882D-162E4F60DBBD.jpeg 833C04B9-D55C-4DFE-8E74-2B9F55939C3A.jpeg

    Attached Files:

  3. upchurchmr
    Joined: Feb 2011
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    Location: Ft. Worth, Tx, USA

    upchurchmr Senior Member

    Put in your wee fillet, or maybe not so wee.
    Coat the inside of the beam, unless you want it to rot and give you a chance to change the design later.
    Looking good.

    On your fixatives for the beam on the inside of the hull, you might put in fillets with some glass to beef the up.
    All the bending load in the beam is going to be concentrated in the beam bolts and hull structure.
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