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  #16  
Old 01-16-2012, 02:13 PM
DIY Tri Guy DIY Tri Guy is offline
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Hi again - Not really sure what it is I'm supposed to be coming up with a name for...

Anyway, I thought you might enjoy an article / blog post where I provide a fair amount of info about the folding amas and E-Z-Up mast & sail rig. This article might already have answered some questions you may have. If not, please feel free to fire away!

It's at http://smalltrimarans.com/blog/?p=7384

Cheers - Frank
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  #17  
Old 01-16-2012, 02:45 PM
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yipster yipster is offline
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Thanks for the story Frank, looks good and build in week you say eh.. hmm..
E-Z-Up is your name I suppose. wiil check my thesaurus later this week.
any pics on the trailer? Was there not also an E-Z cabin cat? Anyway looks good and keep us updated, all the best from a freezing Adam
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  #18  
Old 01-16-2012, 02:57 PM
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Richard Woods Richard Woods is offline
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I have been sketching a 15ft "Raid trimaran" that uses a similar beam folding system. Only my beams fold the other way so they are "fail safe". Relying on clamcleats to hold the outriggers out seems very risky to me

And I will be having a "real" rig (in a keel mounted tabernacle) so it won't be quite as easy to get the mast up. But it will stay up temporarily without shrouds

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  #19  
Old 01-16-2012, 04:34 PM
DIY Tri Guy DIY Tri Guy is offline
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Joe actually misquoted me. I told him I built the hull in a week, not the whole shebang. The other stull took LOTS longer - many months. I just call the mast/sail assembly E-Z-Up partly because that describes it pretty well, but mostly because I just don't have a better name for it.
I really don't think amas that fold the other way are as safe. You hit an obstacle with an ama or aka at any speed, and you're just about guaranteed to break something. I actually gave it quite a bit of thought. I think this arrangement is more "break-safe." Also, they stow better on the trailer.
Please understand, this is by no means a finished product. It's the earliest stages of concept testing. I have several mods in mind already. Is the sail a "real" rig? It sure works like one. But again, much more development will follow. It's definitely not ready for the EC, just for playing around in Terra Ceia Bay.
Hey, I wish all you guys would move to FL so you could stop freezing and start sailing!

- Frank
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  #20  
Old 01-16-2012, 05:01 PM
upchurchmr upchurchmr is online now
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DIY,

Yipster - Adam and I were talking about the triangular fitting/ support which raises the mast and provides support. What would you call it?

Can you tell us how much the whole boat weighs? I know you build quick, cheap, and send the development pieces to the dump, but the weight would be interesting. How much flotation does the ama have at the deck line?
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  #21  
Old 01-16-2012, 05:08 PM
Silver Raven Silver Raven is offline
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Best thing (tri) since 'Corn Flakes'

Quote:
Originally Posted by DIY Tri Guy View Post
Hi everybody - Sorry if I'm a bit late, but I only just found out about this post, thanks to an email from Marc. I'd be delighted to answer any questions anyone may have. I haven't yet posted any info about this boat, the folding amas, or the E-Z-Up mast & sail on my web site (www.DIY-Tris.com) but I plan to do so very soon. The sail rig works well in early tests, though it hasn't been tested beyond wind speeds of about 15 mph. The ama / aka combo works even better than my earlier ones, where the aka tube simply bolted onto the main hull. This folding arrangement, while a slight bit heavier, is also stiffer and stronger. And the 21 lb foam-core amas certainly don't cause much gravity loading. Well, before I get too carried away, let me stop here so I can find out what it is that you may actually want to know.

Cheers - Frank
G'day Frank.

WOW !! How good is this !! The 'ultimate-KISS' goes sailing. Thanks !!!

Sure hope we see much more of this 'F-T' & anyhting else you might have up you sleave, as well??

Thanks very much. I'm 'almost' holding my breath.

What's it weigh - all up? Ciao, james
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  #22  
Old 01-16-2012, 05:13 PM
lumberjack_jeff lumberjack_jeff is offline
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Interesting tradeoff re: folding amas. Is it more important to not break something if you hit an object or more important to avoid accidental lee ama retraction?

If the wind freshens, I think I'd be more worried about the latter.

Nevertheless, this is a really cool idea.
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  #23  
Old 01-16-2012, 05:19 PM
upchurchmr upchurchmr is online now
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Frank probably has more ideas, but I believe you could make a relatively simple locking mechanism for the inboard end of the aka tube. Of couse then you would need a release line to keep the boat quick to open and to fold. If the inner end was locked the strength is not increased by the inboard section in a frontal impact.
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  #24  
Old 01-16-2012, 06:55 PM
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rayaldridge rayaldridge is offline
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This reminds me a bit of the idea I had for a folding cat. I like the idea of a line actuated mechanism, and it would be pretty simple to stabilize the joint with bolts and an I-beam structure. I've been thinking about converting my first cat hull to a tri, after I decided it was too big a boat for the rig I bought for it. The hull is mostly built, and it wouldn't take as much time to build a couple floats as it would to build another big hull, central spine, and beam structure.

Thanks for the inspiration, Dr. Frank! I'm in awe of the number of boats you've built in such a short amount of time.
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  #25  
Old 01-16-2012, 07:40 PM
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Richard Woods Richard Woods is offline
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By "real" I meant "conventional multihull". No disrespect intended.

I agree with the trailering problem. My thinking was that if the outriggers went forward the mainhull would be further back on the trailer. So that it could be launched/retrieved in shallower water.

Check out the Dragonfly trimaran which also has aft pivoting outriggers

Fortunately with such a small boat its easy to adjust the trailering CofG

Richard Woods of Woods Designs

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  #26  
Old 01-17-2012, 06:41 AM
DIY Tri Guy DIY Tri Guy is offline
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So creative minds on this thread. It's a shame we can't all hang out here in FL. Anyway, I'm sure a case can be made for folding the amas either forward or backward. My amas lock in place with simple "clam"cleats, as they are called. Seems to work just fine. I designed them to open by folding backwards partly because I was in terror of accidentally sailing into one our numerous "Slow Down - Manatee Zone" signs held up by two big pilings. (I confess that I'm often looking more at the scenery than where the boat's going
As for naming the triangular piece that is at the heart of my mast raising mechanism, I still don't have any good ideas. It's kind of a pivot arm -- but it's not an arm. Any engineers out there?
The whole boat, all up, weighs 155 lbs -- exactly 5 lbs less than the occupant. The amas each provide 375 lbs of flotation if fully immersed (which they have never been).
As for me building so many boats, I owe it all to my extremely indulgent wife, Laura. (You can see her boat on the front page of my site, www.DIY-Tris.com ) She's an amazingly good sailor, and is the photographer who took the video that's also on the main page of my site. Note please that her boat was going almost as fast as mine (powered only by a single sail of 84 sq ft on an unstayed mast) and that both of her hands were free to operate the camera. Anyway, she thankfully supports my obsess...er, hobby.
Great observation about shallow water launches, which are a serious concern where I live. That's one reason why all my boats can float in 4" of water and sail in 6". (Gotta love those leeboards.) I figured that having the stern of the amas line up with the stern of the boat would provide anti-tipping stability as the boat slides into the water. You know -- three contact points instead of one, even is the outer two are several inches higher. But I also see merit in having the amas fold forward. The biggest mistake I made re trailering we to buy a used one that was too short. It works, but the aft 40% of the boat is unsupported! On the plus side, I don't have to back very far into the water to launch
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  #27  
Old 01-17-2012, 09:29 AM
redreuben redreuben is online now
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Mast raising brace ?
RR
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  #28  
Old 01-18-2012, 01:17 AM
rattus rattus is offline
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Quote:
Originally Posted by DIY Tri Guy View Post
As for naming the triangular piece that is at the heart of my mast raising mechanism, I still don't have any good ideas. It's kind of a pivot arm -- but it's not an arm. Any engineers out there?
Heck, I are an engineer, but think that the brace deserves a proper nautical-sounding name, like "Whuppernarthing" or "Jay-ballard" so as to obscure its true purpose from the uninitiated ;-)

Mike
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  #29  
Old 01-18-2012, 04:05 AM
rapscallion rapscallion is offline
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Originally Posted by rattus View Post
Heck, I are an engineer, but think that the brace deserves a proper nautical-sounding name, like "Whuppernarthing" or "Jay-ballard" so as to obscure its true purpose from the uninitiated ;-)
Mike
You should name it the smoot
Or the smoot arm...
This approach worked for the cunningham, and Tang, the nasa drink... ok, I made up the nasa drink one, but you get the idea
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  #30  
Old 01-18-2012, 08:05 AM
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yipster yipster is offline
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about my terminology: not in any dictionairy but fwd plank as i meant is named a pulpit not a bullpit
so sorry and no new suggestions here for another name for your EZup, sure is a shame whe cant all hang out there all the time
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