Folding beam again

Discussion in 'Multihulls' started by erikhaha, Dec 3, 2010.

  1. erikhaha
    Joined: Sep 2007
    Posts: 43
    Likes: 4, Points: 0, Legacy Rep: 66
    Location: san clemente, ca

    erikhaha Junior Member

    Here is topic that has already been covered before.
    Now I finally have the time to finish building my small tri. 20 ft LOA, 14ft beam. Strip planked, glassed. 1/4" stitched ply outriggers, each approx 60lb.

    I would appreciate any input from experienced builders/designers. Please see attached pdf.

    The hinge has been designed for a 350lb point load acting at the end of the beam. Although I did not do a finite element analysis, I do believe my calculations are a conservative estimate.

    The main beam is a 3" square al tube, and the floding beam is a laminated wood beam made of IPE and Doug Fir #1. The bending stress of IPE is 3600psi, and it is a very very hard wood. Unfortunately its density if 78 pcf.

    Thanks for any input
     

    Attached Files:

  2. dstgean
    Joined: Aug 2006
    Posts: 142
    Likes: 5, Points: 0, Legacy Rep: 68
    Location: Chicago Area

    dstgean Senior Member

    Check out the W17 mentioned here. He uses a waterstay and it also works for the B24.

    Dan
     
  3. erikhaha
    Joined: Sep 2007
    Posts: 43
    Likes: 4, Points: 0, Legacy Rep: 66
    Location: san clemente, ca

    erikhaha Junior Member

    Not sure about waterstays on the W17. I checked it out and I didn't see any. Also, I realy do not want to use waterstays.
     
  4. dstgean
    Joined: Aug 2006
    Posts: 142
    Likes: 5, Points: 0, Legacy Rep: 68
    Location: Chicago Area

    dstgean Senior Member

    Watch the video--I must have been confused by the tramps hanging down. Hinging and not using waterstays will require a BEEFY hinge.

    Dan
     
    Last edited: Dec 5, 2010
  5. cardsinplay
    Joined: Oct 2010
    Posts: 330
    Likes: 3, Points: 0, Legacy Rep: -74
    Location: Camp Plasma

    cardsinplay da Vinci Group


    And a decently strong front beam.

    I'm sure that Mike has calculated all that and that there's a safety margin appropriate for the intended use. Mike is one sharp guy and he is always looking for interesting ways to bring multihull sailing to the every day guy.

    In an area where there was a desert of options for day and adventure sailing trimaran enthusiasts just ten years ago, there are now a collection of insteresting boats. Some of them are very functional, as well as aesthetically appealing and others are decidedly less so, but the choices are now out there.

    If I wasn't for the fact that I've been drawing my own boats of this type for more than nine years now, I'd be very seriously considering one of Mike's offerings.
     
  6. outside the box

    outside the box Previous Member

    JFWIW I hope this might help it is a very simple system by I think by Chris White designs
     

    Attached Files:


  7. basil
    Joined: Apr 2005
    Posts: 154
    Likes: 8, Points: 18, Legacy Rep: 55
    Location: aUSTRALIA

    basil Senior Member

Loading...
Forum posts represent the experience, opinion, and view of individual users. Boat Design Net does not necessarily endorse nor share the view of each individual post.
When making potentially dangerous or financial decisions, always employ and consult appropriate professionals. Your circumstances or experience may be different.