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PostPosted: Sun Mar 11, 2018 5:50 am 
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As a fellow noobie I installed my tramps for the first time in the garage just yesterday to see how everything fits together. Is the extra rigging for the aka collapse required if using the trampolines?

With the tramps installed I could only collapse the akas about 6 inches. Are the tramps strong enough to prevent the full collapse and potential capsize if the pin breaks under sail?


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PostPosted: Sun Mar 11, 2018 6:34 am 
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The tramps should help in the event of a aka collapse unless they themselves are damaged. I would still recommend keep out lines just to be sure. Also, I find I don't always deploy my tramps as it takes extra time so it's good to have a backup.


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PostPosted: Sun Mar 11, 2018 1:34 pm 
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s9utct wrote:
Are the tramps strong enough to prevent the full collapse and potential capsize if the pin breaks under sail?

In my experience yes.
In 10 years of AI/TI sailing with tramps I’ve never broken an aka brace bar pin with the tramps fitted. I’ve never had a capsize either.
Two pin breaks on my AI’s occurred without tramps, with beginners sailing them and colliding with each other. Neither resulted in a capsize and both accidents were in strong winds so a broken pin does not necessarily mean instant capsize. Both managed to sail back to the beach and replace the pin.



Fusioneng has reported breaking tramp buckles in a collision, but his TI is highly modified.

It’s important to know that a capsize can occur with a broken brace bar pin. Being forewarned you can prepare accordingly with keep out lines or tramps, but it is not a given. Capsizes are extremely rare with these craft.


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PostPosted: Sun Mar 11, 2018 8:49 pm 
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Stringy, I note in that video, your ama/aka never folds in fully along the hull, apparently because the paddle in its holder prevented it. If you had been sailing on a 180 deg tack and the opposite aka/ama brace pin broke, your aka/ama may have folded all the way and a capsize might have occurred. All conjecture, of course.

It absolutely makes sense, that some kind of preventative, tramps or keep-out lines, is needed to prevent capsize in case of the brace pin breaking.

Keith

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"Any intelligent fool can make things bigger and more complex ... It takes a touch of genius and a lot of courage to move in the opposite direction." A. Einstein

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PostPosted: Mon Mar 12, 2018 3:17 pm 
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Chekika wrote:
It absolutely makes sense, that some kind of preventative, tramps or keep-out lines, is needed to prevent capsize in case of the brace pin breaking.
Keith


Agreed Keith.
New owners should be made aware that the brace bar pin breaking is the major cause of potential capsize with these craft and be encouraged to fit keep out lines or tramps.
In the video, the reason the bar didn’t collapse backwards was that the operator (not me, one of my workmates) was holding the collapsed aka and pushing it forward. He was in my AI and did very well on his maiden voyage!


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PostPosted: Tue Mar 20, 2018 3:42 am 
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I can't help thinking this is getting a bit out of hand...

"Keep out lines" in some form (basically running diagonally back from hull to outer aka end), will prevent instant capsize if a sheer pin breaks. (you can always fit the new upgraded aka inner ends from Hobie instead or as well)

Small lines tying the inner ends of each aka to its mate on the other side of the hull will prevent disengagement of either aka from hull.

BOTH problem fixed for under $10!

All done, time for a coffee.

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Tony Stott
2012 Tandem Island "SIC EM" with Hobie spinnaker


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PostPosted: Tue Mar 20, 2018 8:34 am 
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I agree with Tony, we don’t need to design a new solution, that’s Hobie’s responsability, just a simple rope does the trick and only takes all of five minutes one time to install, (for the life of the boat, (my ropes and clips are 8 yrs old, whenever we buy a new boat we just transfer them to the new boat).
It takes all of 30 seconds to clip the clips on when you setup, when done we just unclip our clips and stuff our ropes into the mesh pocket for storage.
When we are on small lakes and safe areas, we don’t bother hooking them up, ( no need), you only need them offshore and dangerous conditions really.
No need to overthink this in my opinion.
We just use 3/16” cheap rope from walmart and a couple stainless D rings (2” from home depot). We tie a slip knot on one end of the rope ( like a hangmans noose), slip it over the front AKA hull brace where it attaches to the hull. Now clip the D-ring to the carry handle on the AMA, ( the handle is plenty strong). Then open the AMA and lock it open, now just pull the other end of the rope thru the D ring and tie it off, we use a clove hitch knot. You only need to do all this just one time, (takes all of 5 minutes). Afterwhich the rope stays on the boat forever, just stuffed in the mesh pocket when not being used. We only ever hook ours up when in rough conditions,offshore (easy to clip on even when your already out if conditions go bad).
It’s pretty easy to test, just unhook the aka brace and pull the ama back, it shouldn’t fold in more than halfway, next unclip the front aka bar and try to slide it out, it shouldn’t come out more than halfway.
This fix doesn’t prevent the aka sheer bolts from breaking, or does it prevent the aka bars from coming unclipped and try to slide out. It just keeps the boat from flipping, when this stuff does happen, ( happens all the time to us).
Hope this helps
FE


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PostPosted: Fri Mar 29, 2019 1:38 am 
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Old thread, but worth revisiting!

There are two main scenarios we want to avoid if at all possible.
(1) folding in an ama unexpectedly, and
(2) disconnecting an aka from the main hull or from an ama

Fortunately, these catastrophes can be avoided for minimal cost or effort.
(1) “Keep out lines”. Rig diagonal lines back from hull to outer end of aka. This could be as simple as a dyneema line (Hobie rudder line material), or even cheap stretchy nylon line from the hardware store, running from the front crossbar mounts to a loop over the button on the outside of the rear aka. (Some prefer to run a line from the bow to the front aka outer end instead)

(2) There are potentially THREE separate issues at the ends of each aka…
• While newer Islands have updated joiners connecting aka to crossbar, you can fix ANY model by running a small dyneema loop around the top of the aka hinge pin and clipping it to the cleat under the middle of the crossbar. You will then need to disconnect this safety line if removing the aka from the hull (instead of just folding the hulls together, as many people do)

• While later Islands have fitted double bungees to prevent the aka coming out of the ama mounting hole, you can easily modify earlier models as shown in the photo. Just hook the shackle over the button. You get to determine how much tension you want to add by setting the length of the bungees (they have a knot inside each ama deck fitting)

• The real lifesaver is a dyneema loop (yes, I DO love the stuff!) which you attach to an aka button, while the bottom end has a washer attached, to prevent it coming up through the bungee cords. This dyneema loop is strong enough to take your weight, even without the bungees! That ama ain’t comin’ off!
Image

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2012 Tandem Island "SIC EM" with Hobie spinnaker


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PostPosted: Tue Dec 15, 2020 8:02 pm 
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Here's a question I have not yet seen asked about "hardening" our ama systems: Has anyone tried using these brace lines in a "X" pattern in order to completely sidestep the annoying shear pin?

I sail/kayak the northern part of California's Central Coast (San Francisco Bay Area) and there is nothing pacific about our coastal conditions. Our high-energy beaches are often rough and chaotic with steep beach profiles and large, on-shore submerged rocks, so the rigged boat often departs/arrives the beach pointed in one direction and within seconds is pointing 90º or more away from the desired course due to wave action, which means the amas frequently get side and/or front loaded against the shore. SNAP goes the pin.

In my view, brace lines may be a good solution to these challenging conditions because the lines could be rigged tightly in order to keep the amas in place, yet the lines will offer some relief and recovery. This could be fine tuned by using either pre-stretched or dynamic sailing line.

Thoughts?


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PostPosted: Tue Dec 15, 2020 8:15 pm 
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We did that on all our boats. We used 3/16 paracord, strong but not too strong.
FE


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PostPosted: Wed Dec 16, 2020 3:10 am 
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tonystott wrote:
I can't help thinking this is getting a bit out of hand...

"Keep out lines" in some form (basically running diagonally back from hull to outer aka end), will prevent instant capsize if a sheer pin breaks. (you can always fit the new upgraded aka inner ends from Hobie instead or as well)

Small lines tying the inner ends of each aka to its mate on the other side of the hull will prevent disengagement of either aka from hull.

BOTH problem fixed for under $10!

All done, time for a coffee.



I have to agree. I’ve had my aka try to come out in quite stormy seas but it was kept in place by the cross lines. The reason it had tried to pull out was that I’d broken the front crossbar end due to a combination of stormy seas and my passenger riding the trampoline.

I’ve had a sailing buddy break the shear pin but a combination of keep out lines and his trampoline prevented a collapse. He was able to sail to a beach and replace the pin.

I believe the keep out lines and cross lines are a cheap and simple precautionary installation.

Cheers,
John


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PostPosted: Wed Dec 16, 2020 6:53 am 
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We had our keep out lines ran hugging the underside of the tramp, (helped increase the load bearing capacity of our tramps up
To around 300 lbs, ( a diver in full scuba gear), we also had 4 strait runs of paracord running from front AKA bars back to the clips at the back of the tramp, ( these prevent the tramp from sagging, and having your butt in the water when on the tramp). The 4 lines were permanently attached to the tramp clips so they didn’t increase setup/breakdown time at all. 100% of the time we used the keepout lines, on all TI’s for 8 yrs, maybe 10% of the time we added the second cross line, only when we were going way off shore in rough seas and tough conditions, the rest of the time they stayed stuffed in the rear mesh pockets. They were looped around the rear aka knuckle, with a short piece of spectra string with a cinch knot on the other end that we just lopped around the aka bar and attached to the button on top of the aka bar, ( took all of ten seconds to run even while out at sea).
We used short pieces of spectra, (hobie grey rudder line) with cinch knots on all attachments to the buttons on the AKA bars, this way we could attach several things to the buttons at a time, (always wrap the line around the aka bar before attaching to the button). We often had 3-4 things attached to those crazy buttons like keep away lines, cross lines, rope ladder, ( for 300 lb geared up divers to climb into the boat), and tie downs for our extra scuba tanks, (lashed around the front and rear aka bars), our ama bungy safety straps were also attached to the buttons. We also had the pulleys for our giant spinnaker control lines attached to those crazy buttons, in 8 yrs of super hard use we never damaged a button.
Just tryin to help here
FE


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PostPosted: Wed Dec 16, 2020 10:38 am 
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I guess I didn't make my question clear. I am curious about using brace lines in a "X" pattern in the zone covered by tramps INSTEAD of using the existing Hobie pinned braces altogether. This means completely sidestepping the darn pin by leaving the aluminum brace clipped in its stowed place on the aka.

Such a use implies that some tension in the lines would be needed to keep the amas from being sloppy. I intend to try it out, but specifically I need guidance on the best kind of line to use and how to successfully tension and dog it down so that it stays tensioned. A longer thought is striking the balance between sufficient stability through tension versus shock absorption. The paracord is good for shock absorption and its 500# break strength, but I envision amas stabilized by paracord only would be visibly "active" under sail. Maybe that doesn't even matter.

Maybe a slightly more expensive and complex solution is to include a urethane anchor line snubber in each pre-stretched line because it has a superior rate and range of recovery.


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PostPosted: Wed Dec 16, 2020 11:39 am 
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I understood your question completely. Yes you can, (with the X paracords) un hook the nylon pin brace if you desire, we never did though , we just left the stock nylon pin brace in place. But because our boat was very very fast, (10-12mph average speeds), and we used it offshore sometimes in rough seas, whenever an ama hit a wave wrong , ( like Keith did) at that speed it breaks the nylon pin, (we broke many dozens of pins). Fortunately the keep out lines, and occasionally the X brace lines prevented any disaster or capsize, and as a side benefit, the lines prevented the AMA’s from popping out as well, (which happened a lot on our older models).
One thing to note, because of the location of the nylon pin brace, (1/3 the length of the aka), means any force on the ama is tripled at the point where the nylon pin is located. Meaning if you apply 100 lbs backward force to the ama with a luggage scale, 300 lbs of force is applied to the nylon pin, (the pin snaps at 400 lbs force, (measured)). It just happens the aka bar itself elbows or buckles at around 400 lbs of force, (measured). We elbowed several aka bars over the years, ruins your day. Understanding these stresses and limitations, I always cringe when I see people replace the nylon pins with steel pins.
Don’t take my word for it, measure all that stuff yourselves.
If your life depends on your boat staying together, it’s prudent and recommended to test and confirm the limits of your craft, ( we tested and measured everything).
FE


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PostPosted: Sat Feb 13, 2021 5:44 pm 
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fusioneng wrote:
I understood your question completely. Yes you can, (with the X paracords) un hook the nylon pin brace if you desire, we never did though , we just left the stock nylon pin brace in place. But because our boat was very very fast, (10-12mph average speeds), and we used it offshore sometimes in rough seas, whenever an ama hit a wave wrong , ( like Keith did) at that speed it breaks the nylon pin, (we broke many dozens of pins). Fortunately the keep out lines, and occasionally the X brace lines prevented any disaster or capsize, and as a side benefit, the lines prevented the AMA’s from popping out as well, (which happened a lot on our older models).
One thing to note, because of the location of the nylon pin brace, (1/3 the length of the aka), means any force on the ama is tripled at the point where the nylon pin is located. Meaning if you apply 100 lbs backward force to the ama with a luggage scale, 300 lbs of force is applied to the nylon pin, (the pin snaps at 400 lbs force, (measured)). It just happens the aka bar itself elbows or buckles at around 400 lbs of force, (measured). We elbowed several aka bars over the years, ruins your day. Understanding these stresses and limitations, I always cringe when I see people replace the nylon pins with steel pins.
Don’t take my word for it, measure all that stuff yourselves.
If your life depends on your boat staying together, it’s prudent and recommended to test and confirm the limits of your craft, ( we tested and measured everything).
FE

does anyone have any pictures of these hardening techniques?
i’m about 100 miles south of Sarasota in Cape Coral and recently discovered how easily the shear pins shear on the Caloosahatchie


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