Another Sliding Arm Trimaran

I think it was some 20 years ago that I first did my sliding cross tube trimaran design.   Several other people offered suggestions, some of which were included in the design, including the UHMW centerline dropboard.

Many commentators told me that it would never work.  Several have been built since then but nobody has ever filmed one sliding.  If I had any sense I would have built one instead of the Geko.

I did know that some other trimaran designs had started doing sliding tube designs, but I had not seen one.  Finally some video of  a design at

http://www.astusboats.com/   The tube connections to the amas are sketchy and I see no centerline compression resolution method, but.

the video http://www.astusboats.com/transportable-boat/trimaran/astusboats-sailboat.php?id=266&cat=Videos&page=Videos

ASTUS_20-2_Pres_3D_View1

and here I go again.  20 years ago or so.

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Sunchaser Molds Update

Terrence tracked them down. ” He moved both the  tooling to his shop at Mclelland air force base near Sacramento. Planning on moving to a yard in Columbia to begin production next year. ”  Of course Ollie will forward royalties to both me as designer and Richard who built the molds……What?

He did declare that he invented infusion and a new epoxy that did not need any testing to prove.   Pic below of Teralani 3 that used the Sunchaser house molds.

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New DragonFly or Stuff Done Right

I often see what I think is bad design being foisted onto the inexperienced.  And I call them out.  Sometimes I see designs that look good to me.  The new Dragonfly looks pretty good to me.  Finally amas that are big enough.  A snakey look. Flowing beams.  And of course the required aft swept bows.  I assume they also have improved on the single stainless pin swings in favor of a composite bushing?

newdragonfly

If I may,  all the same features that I put in my 31′ swing arm tri 10 years ago, less the swept bows.

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More Sarabi and the Mast

I finally heard back from Karen on the Sarabi.  “The conclusion is that the top bearing was attached to the mast with a material that failed, causing the bearing to move, which caused the mast to fail just above the bearing.  Thankfully, no one was hurt. Everything above the cabin top went overboard. Cosmetic damage to the boat, but nothing serious. She’s very strong!”

It still seems kind of impossible, even with a failed bearing.  I have begged for pictures of the damage.

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Maybe Stuff Done Wrong?

Customer send me this connecting beam idea and wondered if it would be good on his KHSD tri.
They are from a Scarab 32 trimaran. That unit  looks like a cloned F-boat, including the too-small amas. And apparently they fold, but I could not see how that worked there at the site. What I did notice is these beams look like they take the F-boat beam and strut and combine them in one piece, infilling everything in between.
If I may, that solid wall of beam would have to slam like a mother in waves.  Both of them.  Especially with the small amas.  It looks like stuff done wrong again.  Maybe someone can tell me why it isn’t so.

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