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PostPosted: Mon Mar 05, 2018 5:44 am 
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Location: Massachusetts and New Hampshire - Squam Lake
As a noobie TI owner, I have read many posts about owners addressing concerns of AKA shear pins letting go unexpectedly, or detaching from the cross supports causing a potential unexpected capsize. I had a couple of out of the box ides I would like to float out there for comments, as I would not like to run any more lines as a solution. I was looking for a more effective, simpler, less cluttered, easier to setup and breakdown for trailing solutions to these issues for offshore sailors. These may have been proposed before, but I didn't see anything in my travels on the forum.

Issue #1: Collapse of the diagonal AKA support arms if the plastic shear pins let go
Typical solution: Adding lines from bow, etc. to prevent the accidental collapse if pin shears
New idea: Why not add a second OEM Diagonal support arm to the unsupported AKA? Install similar to original. This still maintains shear capacility in case of impact but doubles strength.


Issue #2: AKA accidentally releasing from where they attach to the cross supports on the hull. (I realize Hobie has issued a recall/free upgrade for this, but for those that want an alternative)
Typical solution: Add small preventer lines or strap pulling AKA's across hull towards each other to secure.
New idea: When arm is installed. Why not simply drill a small hole though both the AKA arm, and AKA receiver on the hull cross support, and insert a simple cotter pin or SS wire through, or use a ball detent pin.

Thoughts?

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PostPosted: Mon Mar 05, 2018 6:43 am 
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For Issue #1: Collapse of the diagonal AKA support arms if the plastic shear pins let go...

I propose that Hobie (or one of us) replace the solid, shear pin protected support arm with a completely new design. This would incorporate a simple gas charged support strut selected for the proper required force. They're inexpensive and readily available in a multitude of sizes and spring rates.

Image

With this design, when the aka/ama encounters a strong force that would have normally sheared the pin to protect it, the gas strut will instead momentarily absorb the shock and then spring right back into position. This would both protect the boat from damage and prevent a capsize from a shear pin collapsed aka.

This should be relatively easy to design and it could be retrofitted to all TI / AI's.


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PostPosted: Mon Mar 05, 2018 7:04 am 
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Location: Sarasota,Key West FL
The issue here is not how you solve the problem, there are hundreds of ways to solve the problems. The problem is the deniers out there that contend there is not a problem, (including Hobie) and doing nothing.

Result is everyone who experiences these problems are pretty much on their own to fix the problems. Many have outlined the root causes, (why and how the problem occurs, and the potential results, (Keiths insta capsize)).
It’s beyond belief that Hobie has not added a simple well engineered solution as a pay for addon to their catalog, they do this with things like mirage drive leashes, anchor trolly’s, rod holders, etc but are silent when it comes to what I consider a safety issue.
I find nowhere in the manual where it says,,, oh by the way if you hit a boat wake, or go in surf, your aka brace is gonna break and you will likely capsize, I looked for it in the booklet and couldn’t find it. For those that are young and fit it’s just funny, but out of shape and older people, or people unprepared that this situation can even occur in the first place are in for a big suprise.

This problem can turn into a life death situation quickly, ( yea even in lakes).
It’s only a complete suprise the first few times it occurs, (ignorance is bliss, ( lol)). After the umteenth time this occurs the rest of us figure out how to fix it and do something about it, on our own.

Annonomous owner (lol)


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PostPosted: Mon Mar 05, 2018 7:56 am 
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This video shows what I have been using for a long time in case of a sheer pin breaking.

https://www.youtube.com/watch?v=ZsoQX7txv6M&t=266s

I have been using the TI since 2015 and have broken exactly one sheer pin - its the "incident" in the video. But I also have not heavily modified the boat or heavily loaded it. I have however sailed in some winds that would be scary on my 26 foot sailboat. FYI, the "incident" here is not at all about right of way. It was about a couple sailors acting like two teenagers who just stole cars and were doing dumb things.

Also later in this video I jumped out of the moving boat. We went to the San Juan Islands later that year in the fall with the TI and I wanted to check the safety of man overboard in warm water (water was likely mid 80's F in this video).

What I like about the setup I have. The safety leash is always installed and all I have to do is to simply clip the quick conect. I like being able to collapse an ama for many reasons and its as simple as just undoing the quick clip and the brace. Super easy to deploy.

The only thing I have changed on that (maybe a couple years now) was to put a bungee in the line which I fortunately have not had a second test on.

Image


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PostPosted: Mon Mar 05, 2018 8:35 am 
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Location: Benicia, CA
fusioneng wrote:
Result is everyone who experiences these problems are pretty much on their own to fix the problems. Many have outlined the root causes, (why and how the problem occurs, and the potential results, (Keiths insta capsize)).
... people unprepared that this situation can even occur in the first place are in for a big suprise.

Annonomous owner (lol)


Boats are not cars. Hobie does a better job than most manufacturers in supporting their toys. And that is the point...it is a toy. I've owned 4 boats. Every one of them had manufacturing issues as well as design issues. I paid $60K for my first boat and paid about $500 a month in keeping it in working order for the 12 years I had it. The Hobie Getaway I had had fewest design and manufacturing issues (maybe because I bought it used instead of new). But I still made modifications to it. One boat had to have the amas redesigned for the location I sail (insufficient righting moment). I'm currently in the process of vetting a $30K boat. Hulls leak, sail controls are sloppy....yadda yadda.

My point is, if you are going to be a sailor. You are going to have to be self-reliant. Boats take you away from help so you must learn to help yourself. Even the toy boats like kayaks and Islands.

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SeaRail 19
Triak
BMW C600
Formerly Getaway with Custom Spinnakers
Formerly raced F24 Mk II


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PostPosted: Mon Mar 05, 2018 9:20 am 
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Joined: Fri Apr 15, 2011 11:25 am
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Location: Massachusetts and New Hampshire - Squam Lake
pro10is wrote:
For Issue #1: Collapse of the diagonal AKA support arms if the plastic shear pins let go...

I propose that Hobie (or one of us) replace the solid, shear pin protected support arm with a completely new design. This would incorporate a simple gas charged support strut selected for the proper required force. They're inexpensive and readily available in a multitude of sizes and spring rates.

Image

With this design, when the aka/ama encounters a strong force that would have normally sheared the pin to protect it, the gas strut will instead momentarily absorb the shock and then spring right back into position. This would both protect the boat from damage and prevent a capsize from a shear pin collapsed aka.

This should be relatively easy to design and it could be retrofitted to all TI / AI's.


I like this idea. Not sure how it would hold up in salt water?

I

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2015 Tandem Island
Massachusetts and Squam Lake New Hampshire USA


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PostPosted: Mon Mar 05, 2018 8:04 pm 
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Joined: Sun Apr 26, 2015 3:13 pm
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bluesman wrote:
pro10is wrote:
For Issue #1: Collapse of the diagonal AKA support arms if the plastic shear pins let go...

I propose that Hobie (or one of us) replace the solid, shear pin protected support arm with a completely new design. This would incorporate a simple gas charged support strut selected for the proper required force. They're inexpensive and readily available in a multitude of sizes and spring rates.

Image

With this design, when the aka/ama encounters a strong force that would have normally sheared the pin to protect it, the gas strut will instead momentarily absorb the shock and then spring right back into position. This would both protect the boat from damage and prevent a capsize from a shear pin collapsed aka.

This should be relatively easy to design and it could be retrofitted to all TI / AI's.


I like this idea. Not sure how it would hold up in salt water?

I

The shafts are stainless steel, it should give many years of good use. They're used on a lot of things subject to corrosion and the same design as an auto shock absorber which sees plenty of road salt with no issues. Worst case is that you would have to replace them for around $20 or so every five years. But I believe it would work and it's something that Hobie should consider over the remarkably poor design using shear pins which protects the akas but puts the owner in potential mortal risk. I'll never understand that.


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PostPosted: Mon Mar 05, 2018 9:11 pm 
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Im not sure I would call the present design "poor" as it has not false failed on me ever and its simple and very light weight. Heavy and fast sailing do not go together.

But.. I do like the gas strut idea. One time I had my wife in the front seat and just did not see a boey and hit it with the Ama. Luckilly nothing broke but I could imagine the gas strut just bending back a little an recovering. Or even the direct impact. Just folds back for a second then recovers.


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PostPosted: Mon Mar 05, 2018 11:36 pm 
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Location: Central Coast NSW Australia
I don’t consider the current design to be poor either but the gas strut is an interesting idea.
Not sure how well the seals etc would hold up in the extreme marine environment though? A couple of telescoping tubes and a spring might be more reliable.

BTW -my 2010 TI is still on its original break away pins. I don’t have keep out lines but I have always used trampolines and it has seen plenty of offshore use, without issue.

My TI was subject to the original free upgraded aka connectors. I considered the pin through aka bar fix while waiting for the upgrade but was reminded by Roadrunner that the knuckles are designed to twist in the crossbar. Any hole in the knuckle would need to be ovalised. It has been done by a member of this forum (can’t remember who) using a QR pin:
Image


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PostPosted: Tue Mar 06, 2018 8:14 am 
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Location: Pula - Sardinia
Hello. I noticed that both the safety solutions that you showed in this thread use a cord fixed to the bar and aka.
Since i am using safety lines between the bow and the aka (near the ama). which differences or advangas do you find between those 2 solutions?


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PostPosted: Tue Mar 06, 2018 9:27 am 
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Im not sure exactly what you are refering to but if it was this one

https://www.youtube.com/watch?v=ZsoQX7txv6M&t=266s

Its a line that is attached to the aka on one end and it attaches to the hull on the other end with a quick connect and the line is captive to the brace on both ends. This method definitely works..

The main advantage to what is in that video is if you ever need to collapse an ama. With the method above, the safety line is removed by simply un-clipping the quick connect.. then the ama can be collapsed in a standard manner. The safety line is also always just stored on the brace so there is zero setup time involved and you dont have to string lines all over. Ads very little weight.

Setup.. just launch the boat as normal and when the ama are out and in place, simply connect the quick connects. The lines is already in place. Nothing more needs to be done.

I find I need to collapse an Ama pretty much every single time I use the TI. It makes using the launching faculties where Im at or visit easier and faster. Being able to collapse an ama is a really great thing about the TI.. something I could not live without.

If you have the lines between the bow and aka, how do you disable the safety if you want to intentionally collapse and ama? I know this can be done but its a little more complex and line runs.

This is another thing about the gas strut idea.. it would also likely be very simple to manage for collapsing an ama.


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PostPosted: Tue Mar 06, 2018 10:36 am 
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The existing aka design is not poor in operation, it very effectively does exactly what it was designed to do, save damage to the aka. What makes it a poor design is that once it does what it was designed to do, it then instantly and unnecessarily results in a major systems failure by collapsing the ama and thus seriously destabilizing the boat. This creates a significant safety hazard by permitting an instant capsize of the boat in potentially stormy conditions which in turn could result in a fatality. It unnecessarily puts the safety of a boat component over the safety of the people in the boat. That should never happen. Operator and passenger safety should be paramount to all else.

And that's what makes it a poor design. The TI was certainly not designed for professional use by very fit, highly experienced sailors, it's marketed and sold mostly to inexperienced sailors, families who take out little children, and people over 50 who may no longer be in good enough physical condition to survive a capsize in a storm.

Consider if the same design was applied to automobiles. Let's say a component in your front suspension system was designed to break away to avoid damage to your car if you did something like hit a road hazard at 55 mph. So you're driving along on a highway and you hit a pothole. Don't worry, there's a shear pin designed to break off so you won't do damage to your car's suspension. The only problem is that once it shears, your suspension will collapse and you may instantly lose control, roll over, crash, and die. But hey, you saved damage to the suspension.

Fortunately auto designers are smarter than that and instead of shear pins they use springs and shocks to absorb impacts from road hazards which then spring right back to normal use without causing either a component failure or a crash.

That's what Hobie should have done and that's what I'm proposing here by replacing the shear pin for the struts.


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PostPosted: Tue Mar 06, 2018 1:59 pm 
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Good points pro10is. You have presented a convincing argument for change.
The gas strut would only work on a TI as the AI brace bar works the opposite way -tension, not compression.


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PostPosted: Thu Mar 08, 2018 1:00 pm 
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stringy wrote:
Good points pro10is. You have presented a convincing argument for change.
The gas strut would only work on a TI as the AI brace bar works the opposite way -tension, not compression.

I've never actually seen an AI up close. Well at least it should work for the TI.

Thoughts?


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PostPosted: Fri Mar 09, 2018 9:04 am 
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Sardinian sailer:
Actually the difference between the the two solutions is the atachment point of the safety line. With the safety line attached from the hull, (anywhere) directly to the AMA, this eliminates the other issue that creeps it’s ugly head. That issue being the amplifying effect, (all force is amplified 3-4 fold because of the location of the brace). In other words if 100 lbs of force is applied directly to the AMA, the force on the brace itself is tripled (300 lbs on the nylon bolt) because of leverage. This is not a problem exept when force is applied at that joint, ( where the brace attaches to the aka bar) it only takes a little more force to elbow the aka bar itself, (around 400 lbs), which happens to be around the same force required to shear that little ball off of your hull. By attaching your safety line to the AMA directly, the failure force is 1 to 1 vs 3 to 1.
The AKA knuckles themselves I don’t think we need to worry about, as I’m sure they can withstand thousands of lbs, same applies with the aka bar tubing, as long as the force is evenly distributed and not concentrated on a single point, the tubes actually withstand quite a bit.
If your concerned about the tubing elbowing and caving in , (folding), you can always fill the tubes with 4 lb urethane foam, (just take the end cap off at the end and pour the two part foam in the hole, (if you pour too much foam in there, as it expands back out the hole like thise 4th of july snake fireworks, and makes a huge mess on your garage floor, (ask my how I know this, lol). The effect is similar to filling a copper fuel line with sand when trying to bend the tubing, ( prevents it from kinking).
I’m just describing the physics involved, ( I physically tested all that stuff). Truth of the matter is any fix you come up with will likely work, (either fix described above by others should work), what is important in my opinion is that we all recognize and understand the potential issue, ( insta capsize), how you fix it or work around the problem is your own business.
FE


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