Hobie Forums

Making the Jib Play Nicely with the Spinnaker
Page 2 of 2

Author:  fusioneng [ Wed Mar 28, 2018 5:47 pm ]
Post subject:  Re: Making the Jib Play Nicely with the Spinnaker

Yea I kinda wish Hobie had made their mast topper taller, (mine is much taller than Hobies original design, I have no clue what their new design looks like), I also kind of wish they had made it a bit longer with the center of rotation off center. Would have saved a lot of headaches I supect.
I suspect the reason mine works so well, (took about an hour to build and has been working flawlessly for 8 yrs now). I still think its the height and the 8-9 inches seperation between the bearings, the point bearing is sitting on top of the mast, and the top bearing is around 8” above the bottom bearing, the top of the mast topper is around 11 or 12” above the top tip of the mast. The entire sail was moved up around 4-5” to give me additional headroom.
I have what they call a point bearing, ( similar to a watch bearing, which is the exact same design Hobie uses at the base of their mast. On the top bearing I thought about using the same type delrin ball bearings Hobie is using at the bottom of the mast ,(where the furler is, those white bearings) but lacked the ambition that day to build it. So I ended up making a simple sleeve bearing. I used a crest tooth paste tube packed with grease, (spins really easily under load), the bottom of the tube, (where the toothpaste normally sqirts out was drilled out so it’s a slip fit over the rod for the pin bearing. Once installed I put a couple loops of elecrical around the rod to prevent the tube from sliding down. That was a really long time ago and it still works just fine so I never bothered making the ball bearing thing, (didn’t need it). I suspect the key to the design is the long seperation between the bearing sets allowing the mast to spin easily, even under load, (just like the design down at the bottom of the mast, which works really well. I just toss my mast topper on the ground, in the sand, etc and never had a lick of troubles, same tooth paste tube and original grease is still in there, (pretty impossible for sand or water to get to the grease). I used the crest with baking soda tube large tube, (lol as if that’s any help).
I have no idea if this will help anyone, just thought I would share how mine works, just tryin to give people ideas, thats all.

Author:  vetgam [ Wed Mar 28, 2018 6:13 pm ]
Post subject:  Re: Making the Jib Play Nicely with the Spinnaker

The problem occurs because the batten flares horizontally when the main sail is quickly furled and it catches/snags the halyard line. Real obvious when recorded in slow motion.The batten is not contacting the mast topper itself. That is why a taller mast topper isn't solving the problem. The topper that I built with shark tubing extends the length horizonaly and that is why it works.

When you furl excruciatingly slow the batten has time to twist and straighten up so that that it does not flare/reach out and snag the line. If you furl at normal speed the batten doesn't have time to straighten up and thus reaches out. The batten is just as close to the halyard line with a higher topper. FE, I bet the bow side of you topper is longer than Hobies and that is your advantage.

Author:  chadbach [ Wed Mar 28, 2018 7:15 pm ]
Post subject:  Re: Making the Jib Play Nicely with the Spinnaker

Thanks Greg. Yeah I would probably end up modifying my topper. It is hollow inside so it should be pretty easy to have a line run through it.

It never made sence to me on how adding only a little height to the Hobie topper would reduce snags. But then again, I've never used it. The length definitely helps, but makes the topper heavier, which is not too big of a deal, but is definitely noticeable when raising the mast.

What really helped me with halyard line snags (front of the topper), is the 2 to 3 feet of pex tubing that hangs from the topper. Unfortunately, the pex won't work with the spinnaker.

Author:  CaptnChaos [ Thu Mar 29, 2018 4:12 am ]
Post subject:  Re: Making the Jib Play Nicely with the Spinnaker

Thanks for the update on the mast topper extension Greg. I was wondering about that but not surprised by the outcome.

I'm in the process of tweaking my spinnaker setup (for the 1000th time) which has a topper based on the design that FE uses. Mine's much lighter than his though. This time I'm adding a backstay to more or less keep the topper aligned where it won't inadvertently twist while furling the main. It will use an extension (like FE's) on the topper so the backstay doesn't interfere with the main while it's gybing back and forth.

Since 2015, the Hobie island series had their sails redesigned with those new battens. Some tangle worse than others where boats before 2015 didn't have any problems with battens grabbing the halyard on all our custom jibs / spinnakers. My 2016 adventure island had terrible problems with tangling the Hobie spinnaker to where I completely abandoned Hobie's setup and went back to my custom topper and hardware (which was only slightly better). However it sounds like people with tandem islands haven't reported as many tangling problems as I experienced so I wonder if the sail shape of the newer tandem is slightly different than the adventure island. Now I own a 2017 tandem so it will be interesting how my spinnaker works (or doesn't) when I finish retrofitting my custom spinnaker setup. FE had an older ti so he never had to deal with the new sail shape and those pesky battens on the newer islands. On my older (pre-2015) adventure islands I used jibs for years without a single tangling problem.

My spinnaker version has the snuffer bag mounted to the bow kind of like the way Triak does their spinnaker ... so it's out of the way. It uses an aluminum bow reinforcing frame and extended bowsprit. Under the snuffer bag will be a "shower cap" cover over the front hatch to keep water off the hatch to inhibit leaking. But the hatch is still easily accessible.

Maybe the spinnaker tangling problems could be resolved if Hobie redesigned the main sails to be more like the pre-2015 AI sails.


Author:  fusioneng [ Thu Mar 29, 2018 2:43 pm ]
Post subject:  Re: Making the Jib Play Nicely with the Spinnaker

Hey: I'm only trying to help here.....
It's unfortunate that the mast toppers are not working out so well, I consider the mast topper on these boats to be the key to everything mod wise, (can't do much with the boat without one), and if they don't work well I would think people just get frustrated quickly and sell or don't use their boats.
We bought our first TI back in apr 2010, on a Thursday took it out twice, got washed out to sea both times, that was the last time I ever tried to sail a stock TI. Ordered my outboard Thursday evening, and picked it up on Saturday morning. I worked all day and night that Saturday building everything, (ie... Mast topper, motor mount, bow re-enforcement, etc), then went out Sunday, and for the first time didn't get washed out to sea and was able to get back in. Since then I've been really happy with everything and have just been using all the original stuff, whenever we get new boats, (we have owned 3 TI's), we just transfer all the old junk to the new boat. My first jib was just a spare Hobie kayak sail I had sitting in the garage, the first spinnaker was left over from our old Oasis, (they both really sucked) I later on made many different jibs and spinnakers, (much later on, (in 2013) I got into the wing sail crap and had fun perfecting that stuff), ended up far beyond even my wildest expectations.

Since then I just use the stuff, haven't made any major changes to the boat in a good long while beyond widening the boat to 12 ft wide in around 2014, (don't remember exactly when I did that, lol).
Pretty much everything was designed on the fly while walking the isles of Home Depot on Saturday, and built in my garage with a hack saw and drill in a few hrs. I'm pretty sure everything altogether didn't cost much over $50-$60 bucks, (much of it I had just laying around my garage, the first outboard was a $500 dollar Island hopper, (the thing sucked)). Most everything was outlined in detail on the Ultimate Island thread many years ago, unfortunately Photobucket now wants $400/yr to store my 30-40 pics, so all those old pics are lost, (I'm not about to pay that much, and don't want anything to do with them anymore).

The actual design of each part is irrelevant, (do it anyway you like), however pay particular attention to the dimensions and concepts of how and why the stuff works and why. For example the bowsprit is critically important, (the mast on TI's is mounted way too far forward), without the bowsprit when going downwind with lots of sails up the bow dives underwater (I call it nautilus mode) and doesn't come back up. Also there is a huge pitchpole risk when the boat is going fast, if you hit boat wakes or big chop the boat easily dives and pitchpoles. The angle on all the foresails also creates lift pulling the bow out of the water. When adding big sailsets, it's pretty important to re-enforce the bow, (you will fold the hull at the front hatch), watch the video to see my bow re-enforcement design, both Chadbach's and CaptnChaos's designs are very good.

My opinion is once you got a good mast topper, everything else is easy.

I'm only trying to help, that's all.
I'll try to explain as much as I have, hopefully this will give people ideas, (everything is extremely simple). I sold the boat and threw everything else away, so I no longer have anything.
Here is an old video of some of my stuff, hopefully you can pause and look some of the stuff over and maybe gleen what I'm forgetting to include in the description.

Here is a pic of the mast topper:
https://lh3.googleusercontent.com/b99E3 ... jLlw=w2400

Here is a closeup of the mast topper:, (lol you can see the Crest toothpaste tube)

Here is the brass drain tube, (home depot)
https://lh3.googleusercontent.com/gcCUe ... 3HQQ=w2400

Here is the ax handle, (home depot), just cut the yellow plastic off, and use the fiberglass pultrusion:
https://lh3.googleusercontent.com/TlfVm ... K4_A=w2400

What I did was just found some PVC pipe and a PVC Tee, ( I don't recall what size the PVC was). I slid the pultrusion into the T so it sticks out 1 ft from one end then 2 ft from the other, (off center). The PVC pipe out the bottom sticks out maybe 3-4 inches, I dropped a 3/8" dia steel rod down the center middle, (which is the pin bearing), make sure the 3/8" rod is plenty long, you can saw it off to the correct length later. To make the thing strong just drop a few drill bits alongside the pultrusion, and a couple inside the T, (along side the 3/8" rod), any size that fits will work. Now tape off the ends, (where the pultrusion stick out, put the whole thing upside down and pour Epoxy into the T, (basically filling it with epoxy), make sure the 3/8" dia rod remains centered.

The brass tube is simple, just run a 5/16" bolt about 3" long crosswise thru the center, that bolt fits in the slot on top of the mast, and can be used to hang the nylon strap that holds the sail up. If you want to raise the sail to get a little more head room under the sail you can also put another bolt a couple inches higher, (thru one side only) to hang the sail on, (optional). I just wrapped electrical tape around the top of the mast to make the tube fit tighter.

The design of the mast topper bearings is the same design as used by Hobie at the bottom of the mast. The pin bearing is simple, just get a piece of cutting board (Walmart) around 5/16 to 3/8" thick, (actual thickness doesn't matter much), and make up a 1 1/2" dia washer with a hole saw (whatever size you need to fit inside the brass tube), then drill an oversized 3/8" dia hole into the washer, (that's the pin bearing, the thrust bearing is the side of that 5/16 cross bolt). I just dabbed a little silicone on mine and dropped into the tube so it doesn't fall out, (the washer sits on top of the 5/16 stainless cross bolt).

The key to the whole design is the separation between the upper and lower bearing sets, (just like on the mast down at the bottom), I think the separation between the upper bearing and the lower bearing is around 6-7 inches.
I was planning on using the same type of delrin white bearings Hobie used initially on the top bearing, but didn't feel like designing it, so I just took a Crest tooth paste tube cut off the bottom, opened up the hole where the tooth paste normally comes out to 3/8" dia, filled the thing with grease, then slid it over the bottom of the mast topper PVC tube, I slid 3/8" id tubing over the 3/8" dia rod, (press fit), which keeps the tooth paste tube from coming off, (electrical tape will also work). It's called a sleeve bearing and spins easily, even under load. I throw the mast topper in the sand and stuff all the time, and never had to do anything with the bearings, no need it all still works fine many years later, so I never bothered designing anything else. The whole works weighs around 2-3 lbs. To test it I put the boat on the ground, (so I wouldn't damage the mast holder), hung about a 28ft rope tied to the front and back tips of the mast topper, (making like a play ground swing), I put the mast in, then jumped up and down on the sling for like 5 minutes (I weighed 240 lbs at the time) to see if I could break anything. I estimated (off the top of my head) that I would need to withstand around 300 lbs force on the mast topper so that was my design goal. That's about the load on the mast topper with 250 sq ft of sail up in 20-25 mph winds. I used the same criteria on the bowsprit, which also is made from a pultrusion. In practice I ended up needing to walk out on the bowsprit a few times untangling sails, and always pick the boat up by the bowsprit, actually when we tow the boat with our bike or our motor scooter, I always just clip the end of the bowsprit to the bike or scooter so it must be pretty strong.

The dual halyard lines (one for the jib and the other for the spin) both run thru a single 3/8" dia PVC tube suspended just below the mast topper, and are tied off to Harken cleats on the front crossbar, (hint,,, wrap the line around the AKA bar brace, then clip into the harkin cleat to hold lines from above... ). Initially I had 3/8" id tubing ran from the front to the back of the mast topper, and tried to do the big halyard loop to the back of the boat similar to what Hobie uses for my spinnaker, I gotta tell ya, the thing sucked big time, so I went to a separate fixed rear stay, and two separate halyards (both running down the single 3/8" tube), which worked flawlessly for many years. When watching the video or looking at the pic, you can see all that stuff.
Most everything I ran always ran on masts with rotofurlers, I had the least difficulty going that route.

Hopefully some of this is of some help to someone.
Edit: if you look closely at the pic of the boat, (lol the one with 6 people on board), look closely at the rear stay line, you will see a 3/8” pvc water pipe that the rear stay line runs thru. That pvc pipe prevents the stay from catching on the battons or tangling up in the sail in any way. The tube is suspended from the rear of the mast topper, (I just used spectra string). The halyard lines also run thru the same type of pipe, the Tube can’t get hung up on the sail or battons even though the tube is fairly close to the mast. The side benefit of the tubes is when I break down the mast topper and the tubes I just fold and lay down the whole works in the hull easily for transport. Because all those lines are inside tubes, they never get tangled up, makes setup and breakdown way faster, (no tangled lines ever), all the guys with all those lines and have to deal with and untangle them all the time (aka spinnaker kit) understand what I’m talking about.
We travel a lot inland, and often have to drop all sails to go under low bridges, it’s pretty easy to put up and take down everything while out on the water.

Author:  Airsails [ Tue Apr 03, 2018 4:05 am ]
Post subject:  Re: Making the Jib Play Nicely with the Spinnaker

Can anyone tell me what the diameter of the hole is in the Hobie spinnaker hoop that fits on the sock is? I have a jib I would like to use but I don’t know if I can drag it through the hole and would like to know before ordering the parts. Thanks

Author:  vetgam [ Tue Apr 03, 2018 5:31 am ]
Post subject:  Re: Making the Jib Play Nicely with the Spinnaker

It is an 8 inch round hole.

Author:  Airsails [ Tue Apr 03, 2018 2:31 pm ]
Post subject:  Re: Making the Jib Play Nicely with the Spinnaker

Thanks Greg, time to start experimenting, cheers Tim

Author:  Pescatoral Pursuit [ Tue Apr 03, 2018 5:33 pm ]
Post subject:  Re: Making the Jib Play Nicely with the Spinnaker

FE, that is quite a piece of work you have there. If there's a Hobie museum somewhere, I hope if/ when you retire it, it ends up there, lol.

In the meantime, a video of that thing on one of your dive trips would be impressive where you get to see all those mods in action.

Author:  fusioneng [ Tue Apr 03, 2018 7:50 pm ]
Post subject:  Re: Making the Jib Play Nicely with the Spinnaker

We have a lot of experience with jibs and spinnakers on TI’s, I’ll share some my lessons learned over the last 8 yrs. via very hard knocks.
1: The floppy windsurfer mast on TI’s makes it incredibly difficult to add jibs to these boats. Keep in mind. Most other boats with jibs have stayed masts, (a huge difference).
1.5 The mast topper in my opinion is the most important component, it needs to work flawlessly.
2: the mainsail on the TI is mounted very far forward on the hull, making it very difficult to add big sailsets to these boats, with 3 sails out it’s near impossible to get enough air in there to get them to perform properly, ( especially a code zero or screecher without a big bowsprit).
3: with the mainsail mounted so far forward, and lack of flotation on the bow causes the bow to dive and not come back up when on downwind with more than just the main, (I call it nautilus mode).
4: We have tried many different jibs, and the common theme is the jib, when hooked up like most other jibs, (without a mast), when the main mast flexes the jib looses it’s shape, making it not very good for upwind to improve pointing). Adding a mast, (especially with a roto furler), changes everything in my opinion. The main purpose for us to always run a jib is we can point much closer to the wind with the jib on upwind, and increases our speed on all points.

5: as mentioned earlier the bow on these boats is not very strong, I suggest anyone making foresails for these boats add some sort of re-enforcement to the bow.

When you add up to about 250sq ft of sail several problems creep up. The AMA flotation is not enough, we had to widen our boat quite a bit to fix that problem.
We tried many different size jibs, 20-25 sq ft is too small to be effective. We had several around 40 sq ft, which were too big for the boat, in our experience around 28-35 sq ft seems to work nicely, having the ability to partially furl in the jib some in higher winds give you the ability to use it in all conditions.
We tried many different spinnaker designs and sizes, giant G2 type spins were great for down wind only, but of little use on any other pointsxof sail. We found the best versatility using screachers or code 0 type spins, not nearly as powerful on downwind only, but way more versatile on most points of sail, (except close reach). All of ours always ran on rotofurlers with masts. I never had much luck with snuffers, though I think hobies spin and snuffer appears to be a very good design.
Hopefully some of this will be of some help.
Just tryin to share what worked well for us, thats all.

Author:  fusioneng [ Wed Apr 04, 2018 10:57 am ]
Post subject:  Re: Making the Jib Play Nicely with the Spinnaker

Pescatoral Pursuit:

When we go out, the last thing on our mind is to take a video, having too much fun, plus when offshore I'm pretty busy, the boat is quite a handful to operate, and probably pretty dangerous as well if you do something wrong, (not forgiving).
In the early years we didn't have any video capability, (video is a pretty recent thing), so anything I have would have been done on my cell, (which sucks)
Here is an example from sometime in 2012, kinda demonstrating the typical conditions we are normally out in (winds under 5 mph):

Here is one video of us snorkeling at Sand Key coral reef (near Key West)

Here is a video of me at lake hartwell GA a couple yrs ago:

This is our old Oasis circa 2008

This is our first TI (circa sometime in 2010)

This is our original jib (circa 2010):

This is our original G2 spinnaker (circa 2010):

Never really had any problems with anything, everything worked fine, I just kept improving on ideas over time, (many different versions of many different sails and sail types).
Unfortunately I sold the boat (health problems), and threw all the mods away, honestly it's only a couple days work to make all new if I ever decide to get another TI, (would be our fourth TI). Maybe someday.

EDIT: To be perfectly honest, I have no clue when I did different mods here and there, it's all a blur now. I just like to work on stuff that's all, pretty much every weekend I tried out a new mod of some sort, just havin fun that's all.

Author:  tpdavis473 [ Wed Apr 04, 2018 4:11 pm ]
Post subject:  Re: Making the Jib Play Nicely with the Spinnaker

Had to laugh. The photo of 4 adults with 2 outboards on the TI reminded me of the original Jaws movie where the guy says, "They're all gonna die".

Author:  prettig [ Fri Jun 15, 2018 3:38 am ]
Post subject:  Re: Making the Jib Play Nicely with the Spinnaker

Guys, own an island for 3 months now and been reading a lot already on this forum (and made some modifications already).

Next thing for me: upwind sailing, so adding a jib (i read all the post and want one, furling) and considering a spinnaker.

BUT I have to set it up on the water !
I live at a lake (so easy to go out), but if i want to go to another larger lake (I live in the Netherlands):
- Need to unstep the mast, fold in ama's, use drives to go through a tunnel and setup again on the water (no beach just docs)
- And it can be rough as well .....mast and tramps I do all the time, no problems but jib, backstay, masttop, lines, etc ....

I might need some smart hooking/unhooking and system to loose and tighten the lines, suggestions ?

You guys have it working and know how to set it up...... what would you changes for on-the-water setting up ?

Page 2 of 2 All times are UTC - 8 hours [ DST ]
Powered by phpBB® Forum Software © phpBB Group