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Here's a couple experiments I'm working on to enhance performance of the Adventure island since I'm entered in the 2013 Watertribe Everglades challenge. The Hakas have been very instrumental in making these modifications possible (thank you NOHUHU). Also thanks to Roger Mann (JollyRoger) who gave me some good jib advice in addition to a couple other of my AI sailing friends.


First speed experiment ...

Haka supercharger using a 1.5 meter Pacific Action Sail from Austrailia as a great way to enhance downwind sailing. Not sure if I will incorporate this design but it was quite interesting and easy to set up and use. It somewhat works for configurations other than downwind but I haven't had enough time to test it out enough.




Second experiment
A furling jib Not only does this jib furl, you can also furl and unfurl your mainsail while the jib is deployed. Plus I can take down and disconnect the jib while underway. As the following video shows, it has a major design flaw in the mast topper which snapped it when the conditions got more intense. The break in the topper was actually a good thing because it taught me what I need to do to build a better topper. The downward pull of the topper was so intense that it broke the topper where the bolt connected the two pvc pieces together.

The pvc pieces were bolted together so I could take the assembly apart in case the bearings needed to be replaced in the future.

The other design flaw in this initial test were the guides for the furling lines were positioned too close to the centerline of the hull. For performance, it seemed opening the jib up more made a big difference. So my next version will incorporate those changes.

For anyone interested in the furling mechanism, here's where I learned how to make mine. http://navigatorjoel.blogspot.com/2010/12/how-to-build-roller-furler-for-under-40.html

After trimming a sail I found on Craigslist, my wife tried sewing it on her sewing machine with no luck. So I found a sailmaker to finish the job and it was well worth the money. The sailmaker was a watertribe sponsor (JSI in St. Petersburg) so that made it even better.

I ran a stainless wire up a sleeve in the sail luft to a swivel at the top toward the forestay where the swivel attached to a line that went through a harken block and back to the deck of the boat tied off to a cleat. By tying it to a cleat, I could adjust the tension of the jib while underway since this was all very new to me. And it worked quite well.

The wooden frame in the front of the AI is attached to the AI metal frame just before the front aka attachment and uses stainless u bolts. This frame is necessary to prevent the front of the boat from buckling with all the pressure exerted from the jib. Without reinforcement of a frame, the AI could buckle in the area of the front hatch.

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Jim

WOW
Jim I applaud your ingenuity and perseverance, keep going!

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Sun E Sailor
Ezra Appel
Palm City, Florida
2010 Tandem Island

Thanks Sun E, Now all I need is for that Surf to Summits seat you recommended to get here.

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Jim

Well I was a little surprised there wasn't much interest in this thread. But in case anyone in the future would like to add a furling jib to their AI, I'll keep posting my notes and pictures. Because I scoured the internet and there were no videos of actual furling jib setups on AI's. And although my videos are pretty amateur, they give an idea how something like this works. It's been a good learning experience for sure.

The previous pvc mast topper was a flawed design but it was for test just to see if this would work. So today I completed a sturdy and I believe safe topper for the mast made out of aluminum using rivets and the same bearings. It's designed so rear stay(s) could easily be incorporated if that's needed in the future.

So here's several pictures of the redesigned topper. The purpose of the washer positioned 1.5" from the bottom prevents the topper from being pulled down any further and pressing on the sail.

The other tweak will be positioning the jib guides out further ... probably on the hakas. Unfortunately there's no wind today so it may be a few days before another test.

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Jim

More interest than you might imagine. Some, like me, are just reading and thinking.

I saw a video the other night of the TriYak with a jib that didn't furl - it "bagged" and "unbagged." Seemed simple. Perhaps another idea to investigate.

Hey Jim.

I think the reinforcement frame and roller jib is quite the achievement. It should take care of the need for speed

As with anything working the bugs out take a few trials and errors but you are making great progress.

My experiments with jib sail has been tentative and used only in light wind. In the pic is my old red hull which I have since replaced with the new dune hull.

I did find the jib creating some steering issues even with the new style big rudder.





Darrell

Hi Tom,
Glad the information is useful for you.

On the Triak, that was their spinnaker "snuffer" you probably saw. I believe it's mainly for downwind sailing and used differently than a jib. But they are quite interesting and simple.

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Darryl, you're one of the reasons I've been trying to speed up my AI. Last time you and I sailed, it took everthing I had just to keep up with you ! So I'm trying to enlist some sailing gadgets to help.

The position of the sail on my jib looks a bit different than the picture of your jib deployed so maybe that's why I had no rudder issues. My jib sail extends out a little farther and spills the wind over the main.

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Jim

You know, I think you're right. I hadn't stopped to consider that it was just a spinnaker. Had seen it and was going to look into a bit more. What they have would be impossible to deploy on anything other than a downwind run.

When will the kits be available for purchase : )

Capt,

I, for one, loved your crazy design contributions. It was just slow here over the weekend and holiday. Everyone was otherwise occupied. (We were Railblazing our boats, out here).

First off, the PA turbo charger is a great experiment. It's one of the first things that came to mind when I started clamping on the Hakas. I was thinking, wouldn't it be cool to put a couple simple foldable windpaddles out there?



The Haka/PA sail combo takes this further and seems a surprisingly good match. Would like to hear more about how this effects performance (speeds with /without), the rudder, and what happens upwind and on reaches. That sail is supposed to have some capability there as opposed to other kayak sail options.

The Jib? This may be the holy grail of Hobie kayak mods. Everytime someone tackles this, I get out the popcorn and wait to read what breaks first. You didn't disappoint!

Once you solve the stress problems, then putting a foresail out there becomes even more practical with a Haka benches to hike on. BTW, I like the way you incorporated the cleats into your Haka extensions, as if you planned it all from the beginning.

Looking ahead, a lightweight, removable aluminum frame base for a jib or genakker might be the way to go. If you build it, we'll be snacking and watching!

How big was this sail, compared with the small Hobie used by others?

Thanks for the comments NOHUHU,

Yeah, the pacific action sail really challenges you if you try using it in close hauled and configurations other than downwind. I haven't used it enough to fairly evaluate it. During experimentation twice it dumped into the water in front of the boat while going forward and it was quite frenzied trying to stop the boat and keep from breaking the sail (a good popcorn moment). For this sail to be useful, it needs a sliding mechanism to allow it to mount from haka to haka (unless you bought 2 of them). So it would always deploy on the opposite side of the mainsails position in a downwind run.

On the jib, I already removed the wooden front platform and am just about finished with making a sleeker and stronger aluminum frame using stock I got from my AI sailing friend Don (who owns a BLUE adventure island !). One thing I didn't mention in the above disaster when my mast top broke was when I shimmied out onto the bow to disconnect the furling mechanism after the jib fell, I heard a cracking sound from the wood with my weight on it. Too much good cooking from the wife is partly to blame.

The size of my jib sail isn't very big. Someone who is more experienced with jibs on AI's told me only a sliver is needed to guide air over the mainsail. And you don't want to overstress the AI.

Oh yeah, those haka extensions worked out very well and I may add a couple more of them. The nice thing about the cleats on them is when I deploy the hakas to put my tent up, the sleeping surface is still nice and smooth. And a tent on the hakas will give me a tremendous advantage in the Everglades challenge. Even if I pull it up to the shore to sleep. No worries about tides coming in.

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Jim