The ultimate Tandem Island (hydrofoils, Spinnaker, jib, etc)

I seriously considered an adjustable bowsprit but we have very limited extruded materials here and it would have been impossible to find the one to slip inside the other so I went for long and could always cut it shorter if need be.

Yes a search for the appropriate figurehead ....Hmmmm we will have to look.

Chopcat,

You asked about the cleat arrangement. Here is what has worked so far but is subject to refinement.

From right to left it is Main sheet, right jib line, main mast furrler, down haul line, left jib line. The furrling line for the jib is cleated by the left pocket where the rudder lock would go. One important thing is to have the curved base with the fair lead guide on all the jam cleats. The angle of the jib lines to the clew of the sail will pull the line out of the cleat without the guide. I'm waiting for two of the bases to come in to complete mine.

Cheers Kona

I got on well with the front brace yesterday but ran out of time to photograph so will post some over the weekend.

I am using the swiveling spinlock cleats for the jib sheet which should deal with the odd angles.

Hopefully there will be progress over the weekend.

Cc

_________________
May the odds be ever in your favor..

Here are the details from the rest of the jib project. First the topper........

I did it all in PVC. After understanding the forces involved I feel it will work fine. I started with a 1" T and put a short stub of 1" pipe on the front, next a 1" coupler with a 1" plug on the end with a 1/4-20 eye bolt on the end. I am not going to use a spinnaker so no need for any additional length up there.

Out the back I used a reducer and 3/4 pipe with a cap and 1/4-20 eye bolt. The length is 24". For the pivot shaft it was a little tricky to figure it out how to use 1" pipe and a 3/4" cap. I found that the 3/4 OD is only slightly larger than the 1" ID so I beveled the end of the 3/4 and chamfered the ID of the 1" and used a large hammer and got a pressed fit then glued the 3/4 cap on.

The reason for the 3/4 cap is that instead of a point bearing I slide a 3/4 cap pointing up down the bore of the topper tube and have two convex surfaces touching on a single point.


So far it has all worked well with no problems and I have had the jib up in some 12kt winds. The Jib sail itself is 15'3" at the luff and 5' at the foot which makes it about 40 square feet. I wanted to have a zippered luff to make it easy to put a 3/4 PVC pipe in it to make the furling easier. Having the tells on it is a big help also for me a novice sailor. A 3/4" cap with a 1/4-20 eye bolt is in the top end and I just drilled a hole to match the shaft on the lower shackle. With the PVC pipe I saw no need for a luff wire.





That is the whole project ....enjoy the video.

Ok chaps - welder mended and on with the modifications.

This weekend it was the bow strengthening bit. I have elected to make this in 20mm stainless as
1 that's what I have and
2 I can't weld aluminium

it is quite light actually as there are only three components. the welding is not that great, but hey...it's a boat

here is the Yak track



the U bolts



the front bit



with the slot in bowsprit





that means i can leave the main frame attached and still use the existing handle to pull it around on to the trailer

We are nearly there I just need to get the furler fixed to the bowsprit and the topper on and then we are off for a try.

CC

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May the odds be ever in your favor..

I really like the setups you guys have, what amazing to me is nearly all the stuff I did, I did back in summer 2010, actually most of the stuff is exactly the same stuff (no changes, actually the exact same units, just all really old looking now (LOL) ) as I put on the boat originally, like the PVC motor mount is the same motor exact mount I built in summer 2010, the 3/8 steel rods are all rusty now, but it's still going strong. I'm on my 3rd TI now, each time I get a new one I just transfer the stuff to the new boat. The brass tubing that I put onto the top of the mast is the same piece I originally put on the boat, I just slip it onto the boat masts each time I get a new boat. Nothing I have requires any mods to the TI itself, it all just slips onto the stock TI.

Of course I've worn out several jibs now because I won't go out without one on the boat ready to use, personally I find it difficult to sail upwind with my TI without a jib, and the extra couple MPH in overall speed is definately worth it to me especially in the typical light conditions we have around here.
I have my boat out every weekend all year round and just love it. It take me 15 minutes to setup (I've posted videos showing me setup) (here it is again for those that may have missed it)
[youtube]http://www.youtube.com/watch?v=Az2_doAgzCM[/youtube]

It takes even less time to tear down, when I get home I just rinse the boat off and pull it into the garage, (takes all of 5 minutes to hook up or put a way). Everything you see on the boat remains on the boat all the time (nothing is ever removed, unless I'm just going kayaking). The jib and spinnaker both run from halyard lines, and I simply furl them up and lay them down on the hull along with the main mast, and strap them down, I leave all the control lines and furling lines hook up.
I go offshore quite a bit (we are scuba divers), and my opinion is the gas emergency backup motor is a must have safety feature. You never know what's going to happen offshore and I always go out with at least 100-200 miles of fuel on board (about 2 gallons), that motor has saved our bacon on several occasions.
Since we are divers we tend to stop a lot and anchor to go diving and snorkeling (more so in Keys West) so I can't imagine not having a ready to go at any time anchor setup, the anchor is suspended behind and above the rear of the boat out of the way, to drop the anchor you simply release the rope, to bring it back you just pull it in, pretty simple setup, nothing to fuss with, 'it's just there to use when needed".

Maybe it's just the local winds in my area that's the problem (5-7 mph typically about 10 months out of the year), but taking my stock TI out in those condition became extremely boring to me the first week I had the boat. I found the stock TI to run about .6 of whatever the windspeed is, so in 6-7mph winds the boat goes about 3mph, (around 4 if you pedal as well (I pedal 100% of the time regardless of conditions (my exercise program).
I for the life of me haven't figured out why Hobie never came out with a jib or spinnaker options for their TI's. When I bought my first TI back in April 2010 I actually went to the dealer to purchase a new H16 (cash in hand), the dealer talked me into buying the TI instead, at that time it was brand new, he explained that they were working on an optional jib that was in testing and would be coming out shortly, which would give the boat better performance upwind and in light conditions (typical around here).
To be perfectly honest I would not have purchased a TI if I had known they were never going to do anything else with the design. Fortunately I have the knowledge to design and build my own stuff, so I went ahead and designed and built what I needed for the boat to suit my own needs.

To the best of my knowledge you guys are the only one's who have modified your AI/TI's to make them what they need to be (in my opinion (or should have been from the start)) in the 4 yrs since I originally posted both the modifications and detailed construction instructions, plus explanations as to why everything was designed the way it was.
I was at the launch of the Wateribe Everglades Challenge at Ft Desoto on the Friday before the launch last week and got a chance to to talk to Jim (chief engineer at Hobie) for a while. He had a prototype spinnaker setup on his AI with a rotating mast topper which wasn't designed right and probably got caught up on his main sail battons everytime he tried to tack, and the front pulley was too close to the mainsail and would have caught up on the mainsail battons everytime he would try to furl the mainsail, Of course I tried to explain all this to him at the time. He had a snuffer bag strapped to the right tramp, personally I tried several snuffer bag designs long ago and I much prefer the roto furling setups (but hey if they can get it to work smooth and easy why not). He let his spinnaker out a couple times while me and Kayakman7 were watching and talking to him, the spinnaker looked to be close to the size of his mainsail. I'm curious how much luck he had using the spinnaker in the race. I had the spinnaker on my boat for the longest time, and found it very useful on downwind (probably the worst point of sail on my TI (with no additional sails), but the problem with spinnakers is they are down wind only sails, and you can only get up to 1=1 with the wind (you can't sail faster than the wind with a spinnaker), so I ended up retiring my spinnaker sail simply because I never used it anymore (sailing with the main to one side and the jib to the other (a batwing setup) gives you almost the same downwind performance if you use a barber hauler on the main). So having a large jib or genoa kind of negates the need for a spinnaker (you don't need both really) unless you do a lot of downwind sailing (most of us don't). Personally I always thought the giant spinnaker parachute on my boat had the biggest cool factor for me (maybe I won't retire it afterall), even if I hadly ever use it.

It just seems to me his spinnaker setup was something he threw together quickly just for the race, and I seriously doubt Hobie is working on anything as far as the TI goes in the area of better sails (jibs, spinnakers, etc), I'm fine with that personally because I'm all set with what I have and very happy with my setup, I just thought others would have the same issues with the stock TI setup as I have (not enough sail) but aparently I'm alone in my thinking, it appears everyone else out there is perfectly happy with the TI unchanged.
I challenge anyone to show me video of a stock TI that can sail almost directly upwind at faster or close to equal the wind speed in light winds (5-8mph, or any point of sail or wind speed for that matter). In the video below I was running the motor at quarter throttle, which basically equals the power a second peddler would be providing (or an evolve if I had one), if I have a second peddler along, I don't need or use the motor at all. Unfortunately with the wing jib the way it was designed I have to have a minimum apparent wind blowing over it (around 6mph) in order for it to work, the reason for the motor is I can' pedal fast enough alone to generate that apparent wind speed over the wing jib. The winds that day were 8mph my fastest speed was 8.7mph upwind (near the end of the video) pointing about 15 degrees off true wind direction (thats 1.1 windspeed upwind). I'm out there sailing every weekend and get the same performance always this wasn't a fluke or camera tricks (in winds 4-8 mph typical speeds are 6.5-10mph, what direction the actual real wind is coming from really doesn't seem to matter much.
Previously shown video of my TI
[youtube]http://www.youtube.com/watch?v=bDGNxvCyVeI[/youtube]

The ball is in Hobies court
Bob

Kona
Love the idea of the PVC topper. it really keeps the weight down and something I might well try.

I presume you have used the PVC adhesive as opposed to any bolts through it?

CC

_________________
May the odds be ever in your favor..

Chopcat.....I love the use of stainless, stronger and easier to care for. It is really enjoyable seeing the creative different versions of the same idea people have done putting their personal signature into the project. I really thank fusion for the inspiration and very well thought designs that he shared with us all. This is not something I would have ever have visualized or attempted without having been able to see it in the flesh.

I will be very interested in hearing your first impressions when you get out on the water. My first was a feeling of seat of the pants torque as opposed to speed and the bow seems a bit more settled and stable. Depending on conditions and proper trim of the main and jib for me adds up to 1.5kts. I always sail with my partner so we make use of the front person hiking out as the winds dictate which makes a huge difference. As you may see in the video I posted everything runs along quite smoothly. We were out the other day with 4 people aboard one on each haka platform and were able to make 5-6kts in a stiff breeze and relatively low chop. I was surprised and pleased by the performance.

I saw no need to add any bolts in the topper the glue joints are very strong. My first topper had a 1/2 inch stainless rod 3' long but when I tried to raise the mast.......Nope gotta redesign that, too much weight. My other issue is that at first the stub on the front was too short and the full length main sail batten would snag the jib down haul line...oops, easy fix. I have had no issues with the latest design.

Wow CC, really coming along there. Certainly overkill with the stainless, so you will zero concerns using it as a battering ram.

I think the track idea is spot on and look forward to you reporting on this setup. After you beat on it awhile, let us know if you feel the side braces, (tied to the Aka crossbars) are really necessary.

That's sprit is a good platform for a furling gennaker, I think. Probably the most useful up/downwind sail we could have.

Y'all are going to have a lot of fun hiking out now!

Thanks Fusion Bob!

Boys, I would not trust PVC alone, glued or not, for any structural joint or attachment point.

However, with a wooden dowel glued inside, it should be fine. After the glue, countersink a couple stainless screws through each of the unions so it bites into the dowel as well.

Also remember white PVC is NOT UV protected by itself. If it's going to get a lot of sun, at least spray-paint it.

_________________

Hobie Island Sailing since 2006

Not here in England it isnt

CC

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May the odds be ever in your favor..

I agree with the statements about not trusting PVC. One of my original mast toppers employed pvc and the jib worked fine for awhile with PVC. But then one day there was a dreadful loud snap and it all came down on me in a tangled mess. Fortunately I was close to an island and able to remove it to get back. Although the prototype I had was slightly different than what you have but there is a lot of downward force on the topper.

But still ... good job cc and Kona on the designs and work you've both put into your jibs. Jim from Hobie recently stated that Hobie is ready to introduce a jib soon. Should be interesting.

No reason you could not run a much thinner threaded rod through the middle with an eyelet on each end if you were worried about it falling apart.
CC

_________________
May the odds be ever in your favor..

Thank you all, I appreciate all the input on the topper. I had considered other materials but the weight was more than I wanted. I did read the post from CaptnChaos and so evaluated the use of PVC carefully. Since the ends of the topper are essentially seeing only tension because as the jib gets more load from the wind the topper rotates and that keeps the ends in mostly tension (pulling force). The part of the topper that slides into the mast extension will see the most side load and seems strong enough. I have done many projects with PVC in the past and am aware of how tough it can be if used properly.

I may be wrong........but other than painting the topper I am going to let it go as built for awhile and see how it goes. We will call it a test topper. I did have a line on a carbon fiber rod for the horizontal piece and still may do that in the future. There was an incident where the front plug on the topper come out after a few trips because I forgot to glue it in! Did I feel silly . The sail came down....no biggie rolled it up and laid it on the kayak and sailed on in to port on the main.

It will sure be interesting if Hobie does come out with a jib kit to see how the system is designed.