Folding Sail Rig

Hi Guys/Gals,
I would like to build a sail rig, but I need to reduce the overall width to make use of the launching area at the dock that we use. Once the rig is in the water and I'm in the cockpit, I would extend/unfold the rig.

Has anyone built a folding sail rig?
If you have, can you please share some of the details?


17 replies:

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RE: Folding Sail Rig

Hoping that either (a) you DO build it, and and the following opinion is wrong, or (b) the following opinion is right, and you don't build it...

The folding rigs I've seen have been only on expensive boats.  Why, John H. himself is an inveterate boating idea tinkerer--and in his misspent youth, a  borderline multi-hull crazy--and yet I can't think of a picture I've seen of a folding rig from his studio.  Yes, I'm sure he's built one, but he's made sure to destroy all the negatives.

Why? A couple of reasons.

Firsst I think it's because they are complex and expensive. ( They are cool, got to've probably seen those racing or cruising trimarans where the amas have four-bar linkages, and they kind of tuck themselves partly under the sheers when the boat's on the trailer.)

Second, I've not seen them more simply because I live 11 hours from the beach and don't get out much, and as soon as I mash the "Submit" button, three builders will put up posts saying that they found a good folding rig at the local Home On De Pot for 29.95 Candadian, one of which came in fourth in the Bermuda race with no significant damage,  in spite of being run over by a small oil freighter during a Force 5 gale.

It never fails.

Therefore, as tempting as a folding rig is, you should pick some other solution.  (a) Be happy with the simplicity but low performance of a monohull rig, or (b) find a better launch site.

Very Truly Yours,

The Naysayer


RE: Folding Sail Rig

I've been contemplating such an idea, for somewhat diffent reasons. I want to be able to paddle when the wind dies without being constrained by the smaller paddling area between the iokas. Also, one of these years I'd like to try Watertribe's Everglade Challenge, which has "filters" that constrain the size of sailing rigs. That said, my ideas might not be suitable for your purpose.

Here's what I'm thinking:

Cut the iokas on each side fairly close to the hull. Attach a strap hinge to the top of the ioka and a barrel bolt/sliding bolt on the bottom to make the ioka rigid when in sailing mode. Run a straddle line of appropriate length between the bulkheads on each ama. Attach a line to each straddle line and run them up to blocks on the mast. ( My sail is attached with a series of rope hoops so I can do this ) When desired the amas could be raised out of the water and folded against the mast by hauling in the lines running through the blocks. I can foresee two problems though. The side of the ioka that has the leeboard will need to be cut further out from  the other possibly creating an imbalance. Also, I'm not sure what effect two amas waving overhead would have on stability. I might be able to get away with it because the Sailrig is mounted on a Triple, which is a VERY stable platform.  Oh, and working up the nerve to perform major surgery on a perfectly good boat. Shudder!!! 

RE: Folding Sail Rig

Hi George

I'm not sure what you mean by folding rig, but I have a similar problem launching my Skerry. some of the ramps are not very wide and the dock is sometimes very high depending on how high the water is. I set up my rig so that I had a line that would pull my boom up. 

I set up on land, bring the boat to the water, fold up the boom so that it comes up to the mast, then after I have launched and am clear of the concrete, I just loose the rope and my boom and sail falls into place. I then tighten the downhaul and I'm ready to go. 

The sprit seems to not get in the way.

Its a very simple line that runs from the middle of the boom (where my block is attached) and runs up through the eye that controls the snotter and comes down to be attached to the cleat that I use for the downhaul. 

It works really well.

On the second photo from the top you can see the line sort of. 

I also use this line if I want to row for a while while the sail is still up. It takes the boom out of the way.


RE: Folding Sail Rig

I have not built one, but they do exist.  Hobie has a folding rig for its kayak sail set up.  Hear is a link.  I could not find a pic of it folded.  Perhaps you could duplicate it in homebuilt form.

RE: Folding Sail Rig

The Hobie set up is what gave me the idea. I just want to keep everything wood. This is going on a Mill Creek and having metal tubing just isn't going to look right. I have a wooden hinge idea that I may make and test.


RE: Folding Sail Rig

>>>>>Cut the iokas on each side fairly close to the hull. Attach a strap hinge to the top of the ioka and a barrel bolt/sliding bolt on the bottom to make the ioka rigid when in sailing mode. >>>>>>>

Egads.  From your description I don't think this will be nearly strong enough.  You'd need big, heavy metal plates at the very least, with the thickness of the akas doubled in the vertical dimension.  There's several hundred pounds of load concentrated at the joint when the trimaran is sailing fast---the peak loads in gusts may be 500lbs!  As my engineer father would say:  "The engineering challenges are non-trivial" with such a rig.

>>>>>>Run a straddle line of appropriate length between the bulkheads on each ama. Attach a line to each straddle line and run them up to blocks on the mast. ( My sail is attached with a series of rope hoops so I can do this ) When desired the amas could be raised out of the water and folded against the mast by hauling in the lines running through the blocks.>>>>>>

You mean the amas would be five feet up in the air!?  Eeeeeek.  Not even a Chesapeake Triple has the stability to deal with that.  The kayak would quickly shift to "Stable Two":  90 degrees over on its side, both amas back in the water.

There are plenty of folding trimarans on the market (all big).  Studying what they've done would be a first step.  You'll need a folding-scissors sort of thing. 

Farrier F-22:



RE: Folding Sail Rig

I recently built a CLC sail rig for my kayak and I made a few changes to it.  Let me tell you, the small changes I made, caused a HUGE amount of extra work and headache.  The crazy thing is that all I did was change the sail plan and change the way the akas attach to the boat.  I have also had problems with my rudder attachment because the stern of my boat comes to a point.  I have learned first hand about the incredible amount of force involved in sailing.  

 I think introducing some kind of folding design would be way too much work and headache.  I would suggest either finding a better launch spot or using a small sailboat that could be rowed when the wind dies.  

 BTW you can read about a few of my problems in my thread Hybrid sail rig almost complete.   

RE: Folding Sail Rig

I have to respectfully disagree with John regarding the points he made about a folding ioka. I should have fleshed my ideas out more thoroughly. As far as a locking hinge goes, I can imagine a number of designs that would be as strong or stronger than the ioka itself. It’s really just an issue of transferring loads. Unfortunately, I don’t have access to a program that can easily render what I’m thinking. Something along the lines of a top mounted hinge with flanges extending down the sides and then overlapping flanges crossing the opening and then, say, a bolt through both flanges and through the ioka on one side of the hinge. As long as tolerances are tight most of the forces on the hinge hardware would be in shear and the ioka itself would have to break before the hinge would come apart.


To put this in perspective, consider the attachment of the SailRig to the kayak. This is accomplished by only  4  ¼ inch eyebolts penetrating less than an inch of softwood.  And at any given time only two eyebolts with a direct pull in less than 1 inch of wood are holding 500 lbs of pressure. If this arrangement can hold (and I can assure you I’ve tested it thoroughly J ) I’m sure a well designed hinge would hold up, especially given that the lever arm at the hinge is smaller resulting in a proportionally smaller force on the hinge than on the eyebolts. I’m pretty sure I could make one using off the shelf items from Home Depot but having a welder brother-in-law doesn’t hurt!


As far as iokas that “scissor” up to the kayak go, this solution doesn’t address my problem with paddle clearance. I love the Triple w/SailRig and find that 90% of my boating time is with this configuration. However, a few times I’ve been becalmed and had to paddle it in and it’s not a lot of fun. I’ve done this solo from the center cockpit and also with a friend in the fore cockpit and myself in the aft. Paddling in all cockpits is frustrating because I always need to take truncated, choppy strokes and my friends say the same thing. A folding ioka that brings the amas right along side the kayak makes paddling impossible.


I should have emphasized that I would not be paddling with the iokas fully overhead. If the iokas were raised by even just a foot, I’m sure I would be able to take relaxed natural strokes. I’m not sure how much stability would be compromised by raising the iokas by a foot or so but I’d imagine at that height the amas still would provide a righting moment and be more stable than a non-sailrigged kayak.


I also think that an ioka that folded up to the mast would be a good solution for a dockside entry. An ama along the side would require the skipper to scuttle over the ama to get in the cockpit and, unless the ama is deep in the water, the kayak/ama combination might be initially unstable because of the different hull depths.  An ioka folded to mast would allow a more direct entry.BTW, a ioka folded to the mast would only 3 ½ ft high ( 10 ft – 3ft of aka on deck divided by two.)

 Anyway, enough of my blathering. Talk is cheap. It’s time to put up or shut up. I’m going to cobble up some folding iokas out of scrap and see if my predictions about stability are true. If it works out and I can design the hinge, then maybe I’ll have enough nerve to take a saw to: sailrig 1sailrig 2

RE: Folding Sail Rig

Rats! I can figure how to build a nice CLC boat but I can't figure out to attach pictures. Any anyway these areare links to boat pics, I think.

RE: Folding Sail Rig

That's OK Dusty, that's what we're here for. You're right, BTW. Nice boat.



RE: Folding Sail Rig

PS - What's an "ioka"? All I get when I google it is the Lakota masculine verb for beauty or a Japanes boxer.

Maybe you guys mean "aka"?



RE: Folding Sail Rig

>>>>What's an "ioka"? All I get when I google it is the Lakota masculine verb for beauty or a Japanes boxer.>>>

I've not heard of "ioka."  By convention, in the Western outrigger canoe world, a crossbeam is called an "iaku", whereas in Western sailing multihulls, a crossbeam is an "aka" and a float is an "ama".

To my limited understanding, all of these words would be unfamiliar to a native of, say, the Marshall Islands.  We Westerners play fast and loose with native terms.  I definitely flinch when someone calls a paddle an oar, but for all I know "aka" means "latrine" in Marshallese.  Perhaps a movement should be started to call these things "crossbeams" and "floats."

RE: Folding Sail Rig

Everything, including the plans for the CLC sail rig, that I have ever seen has labelled floats as ama's and crossbeams as aka's.  Having lived and traveled in various parts of polynesia these seem to be fairly universal terms for these parts.  I have never seen either ioka or iaku.  My suggestion is to follow John Harris's (the designer) protocol and use the words aka and ama or the english crossbeam and floats.  This way confusion can be minimized.  

RE: Folding Sail Rig

Ama with you, Synonymous.  Aka not think of any reason to use these pseudo  Polynesian terms, which are probably imitation psuede, anyway. And Laszlo, we don't need to know that they prefer iokas in Japan.  TMI, to be brief.

Dusty, although I am a poi excuse for an engineer, I see your point that you could easily make the hinges you describe as strong as, or sronger than the, the...the crossbeams.  Your design is ingenious, and you married well too--a brother-in-law who can weld is a gift to be treasured, like a father-in-law with a place on a little cove on the Eastern Shore.

But still I will lei a hula't of money on this: that folding contraption will turn out to be just too complicated.

Speaking of non-Western marine architecture terms, is it an Occident that john recently mentioned that fancy "or" (oar is it "paddle"?) used for sculling over there? Maybe you should listen to the real "proas" and switch to a form of locomotion that steers clear of the, the, you know, them boards that hold the floats to the boat. 

Sculling is probably less efficient than paddling, but it might solve your problem, and 90% of the time you are sailing not paddling.

RE: Folding Sail Rig

I got this term from Gary Dierking for the thingies that connect the whatchamacallits . Mr. Dierking, if not the world's foremost authority on Micronesian multihulls, is the world's foremost enthusiast of same. He is also a damn fine designer. Gary makes a compelling linguistic argument that the term "aka" does not exist in traditional multihull naming conventions. Being an insufferable word nerd, I  couldn't resist the opporunity to shamelessly inject the "proper" usage into the  discussion. Mea culpa.

RE: Folding Sail Rig


I've been lucky to have followed Gary Dierking's work since the 1990's.  I love his designs.

Just got his book last week---it's really neat.

Jargon, shmargon.  Last I heard, "ama" means "log" in Micronesia, and "vaka" (Western for "main hull") just means "boat."  I'm never dogmatic about the strange argot of the yachting world---most of it is just made-up, anyway.  I'm for "crossbeams" and "floats," myself. 

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