Sailing sit on top.

I thought someone might be interested in my latest project:
This is a sit on top I’ve rigged for sailing. I’ve just sold a Hobie revolution which was marvellous but unfortunately just a little big for transporting on the top of my smallish ASX. Previously I converted two Canadians for sailing and both worked extremely well, I was just a little concerned about such a short platform (2.6m).

I first bent up a 25mm x 3mm round ally tube frame on which to mount the mast and the leeboard. The tube follows the shape of the front section of the sit on top and then extends down the right side for a short distance for the leeboard. The frame is fixed to the hull by three clamps and three large ally washers supporting the hull internally. The mast mount is a bicycle handlebar mount. The stem end is 28mm so I had to bush it down to 22mm to take the mast, the handlebar end is 31mm so I also had to bush it to accept the 25mm frame I bent up. The bushings are just simple PVC and aluminium tubing slotted to conform to the sizes required. The leeboard mount is comprised of two 25mm ally clamps I machined up, mounted together with a piece of 5mm ally plate drilled to accept a 10mm bolt on which the leeboard swings. I made up two leeboards, one 600mm long the other about 800mm long. Both are made of 17mm ply and are damped by two 65mm plastic pressure washers. The rudder is also made from painted ply but only 10mm thick.

The rudder mount is just two plastic bimini hinge mountings fixed to the rear of the sit on top via four S/S bolts supported inside the hull by a largish PVC square plate. To assist assembly I had to drill a 25mm whole which I filled with a standard Kayak bung after fixing the rudder mount. The rudder assembly is made from PVC and 3mm ally which supports the ply rudder between two 50mm circular plastic damping washers.

The mast and sail are standard hobie kayak items I retained from the revolution. The Hobie sail kits are boomless so don’t perform too well downwind. To solve that problem I made up a PVC and ally boom. The boom has an ally cleat for outhaul only. I want to add a vang also but first I have to work out where to anchor it. I also want to convert the mast step to a loose step so I can install a furler I’ve made.

I made this for use on rivers lakes, etc, when we take off with the camper, it’s short length and lightweight making it easy to top and transport. I’ve only had a chance to sail it twice, both times in the ocean. Once in very light wind conditions, the other in light gusty conditions. Both outings were successful the kayak pointing well, turning quickly with no indication of languishing in irons and it also handled downwind runs well. It was a little ’tippy’, but that’s to be expected in a hull with only a 75mm beam. I should add, whilst ‘tippy’ it’s not tippy to the point where I get wet.

There is one of those Hobie trimarans sailing about here. I was impressed how well it sailed but I see now from your link Cisco they might have been cheating! I did not realize they had the foot control paddles.

Some very odd replies here, I’ll try and address some of them though. I sail it without pontoons as I did the Revolution before it (lots) and managed to get somewhere, a lot quicker than had I paddled or pedalled. My SOT is meant as a simple craft I can take with me when towing my Aliner. It gives me the option of paddling (only if absolutely necessary) or sailing while not taking up too much space, not adding too much weight and not affecting fuel consumption.

I had an Adventure Island before the Revolution, it was a barrel of fun, quite fast and very wet. Car topping an Adventure Island isn’t easy (very wide even with pontoons disconnected and there are lots and lots of other bits and pieces to carry along with it, enough to fill a car, so I made a trailer for it. Unfortunately, when towing a van the law forbids me to also drag a trailer behind as well. With that in mind I bought the Revolution and the sail kit. Again, it was a barrel of fun, quite fast (certainly faster than pedalling) but nowhere near as wet as the AI. But again, due to size I sold it and rigged the SOT for sailing. I can top the kayak and take it with me when towing the Aliner and travel at the legal speed limit without problems (not so with the Revolution) and without affecting fuel consumption (not enough to worry about anyway). Many years ago (late 70s early 80s if memory serves) I was topping a surf ski and kayak on a Gemini sedan, the wind from an oncoming truck tore the surf ski and kayak of the roof, racks still attached. In the process the L shaped brackets were bent straight and I had to have the gutters (remember those) repaired and re-painted when I reached Adelaide. The noses of both surf ski and kayak also had to be repaired Today I’m careful topping anything longish and prefer to use a front tie down strap.

I’m a great fan of cartopping my kayak, the fuel consumption with kayak on top as opposed to no kayak on top varies by under 1 lp 100. When towing the AI behind I used an extra 2-3 lp 100, no brainer for me. Streamlining on top as opposed to on trailer is obviously better because on top you don’t have the brick like aerodynamics of a trailer: mudguards, mudflaps, chassis, etc. Again, no brainer for me. I suffer quite badly from OA in hips, lumbar, cervical and thoracic spine, shoulder and elbows, and yet, I have no problems getting the SOT up there. There’s a lesson there, be very careful when choosing parents, not all parents are created as ideal!

If your fuel consumption goes up by 50% when topping your yak, I’d be looking for another car I think.

Wish I had known about your intended 130kph trip to Bundaberg, police are always interested in removing irresponsible drivers from our midst.

Ramona. The foot controlled paddles you refer to aren’t paddles, Hobie refer to them as fins. But to be accurate they are flippers and they mimic the movements of a turtle. When sailing the fins are kept together vertically by the feet on the pedals, so acting as a centreboard. The only time they come into play is if you get stuck in irons. At any rate, trying to pedal an AI at the speeds it is capable of (even with optional turbo fins) would slow you down. Certainly in very light almost none existent winds they may be useful, but in winds any stronger they would hinder more than help.

Sectorsteve. Quite right, anything with Hobie on it costs a bomb, another reason I sold my Revolution ((around $2700 with sail from memory). My SOT was only $300 on sale at BCF, the sail I already had and the other bits were just bits and pieces I had lying around.

Wollemi. I don’t buy watercraft for looks, I buy for usefulness. I fitted the SOT with sail so I wouldn’t have to paddle, being 2.5m it never gets stuck in irons and the leeboard can be removed in a few seconds. One of the reasons I added the sail in the manner I did was so I could also use it as an SOT. Incidentally if you want to paddle with the leeboard in place (why I don’t know) you simply angle it down a little and knuckles don’t go anywhere near it.

‘Don't fit a vang - there is limited room to move on a kayak already. It may restrict your vision further’. You’re kidding right? A piece of 4mm (at most) chord is going to restrict my vision and take up room. Again, you’re kidding right?

‘A paddle-blade in the water gives stability’. Well I’ll be darned, who would have thought. I don’t fish personally, but I’ve never capsized a canoe/kayak, not even when under sail. As for narrow beam craft being ‘tippy’, well I suppose it’s just physics isn’t it. And common sense of course!

Your links are all very nice I’m sure, are you trying to sell me something? Sorry but I moved on from paddling kayaks and canoes a long time ago: river kayaking, sea kayaking and slalom kayaking no longer hold interest for me, I’ve moved on.

I hope that’s not you in that picture under the bridge??? Most people look before they leap!

These replies seem to assume me to be a novice. You know what they say about assumptions???
As well as sailing my current SOT, I have also owned and sailed a Hobie Revolution, a Hobie Adventure Island and the two Canadians I mentioned. Aside from them I have also owned and sailed a Dennis, trailer sailer, a Tropic trailer sailer, an International 470, a Walker Bay 10 and a Mirror. I also raced a Club 88 Land Yacht at Lake Cooloongup (almost dry lake) in WA with the Sandgropers Land Yacht Club. Aside from that, not much really, just a couple of boats, a couple of canoes (converted for outboard use), a sea kayak, a couple of slalom kayaks, a couple of short (7/8’ surf skis) and a couple of surfboards.

An expert? Certainly not, certainly I wouldn’t presume to tell anyone how to do anything, and never what they should be doing (isn’t that refreshing) but neither can I admit to being a novice. Incidentally I made the sails for the two Canadians myself, after a lot of study of course; and, after seeking advice from a friend who just happened to be – a professional Sail maker.

So, why did I convert (re-invent if you like) an SOT for sailing – simple really, for the same reason I do anything these days - I enjoy it. I’ve also built (again, re-invent if you like) several motor cycles, a ride on, a motorised wheelbarrow, a wood lathe, a couple of houses, a career, a computer, four Victa engined kiddies go carts, a kids mini bike, a life, a motorbike engined go cart for me, and many, many more things, all for the same reason - I enjoy it.

Yes, I am old, some might say very old, but of course I would argue that!

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Ramona said..
There is one of those Hobie trimarans sailing about here. I was impressed how well it sailed but I see now from your link Cisco they might have been cheating! I did not realize they had the foot control paddles.

A mate who has one says two people pedalling can get one of these things going at 5 knots for about 50 seconds.

But they are quite ingenious. Steady pedalling will keep them moving at a knot or two which is what you need glassed out with no wind. They point surprisingly well for what they are. I watched from the beach at Bargara with about 15 to 20 knots wind and he was able to put it wherever he wanted it.

The little flippers act as mini fin keels when sailing and fold up horizontally when beached. They also have paddles but I suspect would be tiring and difficult to use with the pontoon arms in the way.

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manfred said..

Wish I had known about your intended 130kph trip to Bundaberg, police are always interested in removing irresponsible drivers from our midst.

What I said was:- Normally with nothing on the roof I will get 10l/100k economy from this vehicle travelling at up to 130 kmh.

Meaning, not with scull, cradle, roof racks atop or trailer behind. I only ever travel UP to 130 kmh on dual carriageways where the posted speed limit is 110 kmh and traffic is little to none. Condemn that if you will but I am always aware of my responsibilities and that is why I towed a trailer behind yesterday because of the rear overhang of the 8.5 metre long scull. Saved getting fines as well.

The transfer of the scull to Brisbane went well and as expected the fuel consumption went up but not to 15l/100 klm. The figure was 14.25l/100 klm. Once the scull was unloaded, the fuel sucking cradle and roof racks were removed as well for the trip home. I don't know what my fuel economy was for the trip home as I have not topped it up yet.

In your first post you did not mention you would be towing your Aliner behind your smallish ASX, whatever they both are and therefore would have to car top the kayak by necessity. So I was not really making any assumptions, I just did not have all the information.

You have done a great job adapting the kayak for sailing and if it works, it can't be faulted. I envy your workshop facilities, which appear to include a lathe, tube/pipe bender and aluminium welding capability. Very neat workmanship too. You remind me of a couple of other tinkerer types over in W.A. Must have something to do with the weather or the isolation maybe.

Your photos don't show where the rudder control lines lead to. Is it a foot steerer? Could you post a pic of the "cockpit" please?

You have only mentioned sailing capabilities in very general terms and I see that the leeboard position can be adjusted fore and aft by about 300mm. How well does it point and does leeboard position adjusting have any effect on it?

Just a couple of places in your first post where I am assuming (correct me if I am wrong) you missed putting in a zero.

The rudder mount is just two plastic bimini hinge mountings fixed to the rear of the sit on top via four S/S bolts supported inside the hull by a largish PVC square plate. To assist assembly I had to drill a 25mm (250mm ??) whole which I filled with a standard Kayak bung after fixing the rudder mount. The rudder assembly is made from PVC and 3mm ally which supports the ply rudder between two 50mm circular plastic damping washers.



It was a little ’tippy’, but that’s to be expected in a hull with only a 75mm (750mm) beam. I should add, whilst ‘tippy’ it’s not tippy to the point where I get wet.


For it's size at 2.6m one of these could be quite handy on a 30 foot cruising yacht. What brand of kayak is it and who sells them?

Not complaining about it just noting it. Also fuel was a lot less expensive back then. Even with roof racks alone there is a substantial difference in fuel consumption.

Now that I am on a fixed self funded retirement income that is less than the pension, I do have to note where every dollar goes.

I don’t have an ally welding capability (yet), so everything bolts together.

The rudder lines are routed in a continuous loop through 4 ally pulleys I spun up, two at the rear either side of the tiller and another two either side and forward of the seat. The rudder can be controlled from either side or by the line routed across the kayak’s deck just forward of the seat. The rudder is damped by plastic washers a little so it doesn’t require hands on all the time

The centre of the leeboard mount slide is roughly just behind the sail C of E to allow for bend in the mast when the sail is sheeted in tight and also for weather helm.. Further adjustment can be made by tilting the leeboard fore or aft. Depending on whether tacking to starboard or port the position of the leeboard changes. The leeboard can be swung forward of aft to compensate. Theoretically, minor steering changes can be achieved by juggling leeboard position and sheeting in/out..

The 25mm hole is correct, it was drilled to enable the insertion of an allen key into the hull. The allen key was necessary to engage the bolt heads of the rudder mount brackets. Pointing is quite good; however, as the kayak has a smallish sail area, pointing can be slow in very light winds.

There are other kayaks better suited to sailing than mine, I just used this one because I already had it, but certainly it is a better hull shape for sailing than a see yak. Because of a kayaks narrow beam I think an ideal hull shape would be flattish with hard rails (chines) and moderate rocker JMO…

I only converted this kayak because I can chuck it on top of the car when we go off camping. Allows me to explore lakes and rivers without paddling. I hate paddling.

Thanks for the info and pic. Must have been a bit fiddly getting the rudder pintles bolted in but you got them there but what about the backing plate?? Blu taced on the end of a stick or something.

I have never used a kayak so I will see if I can borrow one before I spend any money. I have a Walker Bay 8 that I use as a utility tender in port but it is too bulky to use as a tender on my 30 foot yacht when cruising. Too big for the fore deck and I don't want to spoil the yacht with davits on the stern.

I was lucky enough to score an Avon Redcrest in good condition which I use for cruising. Cheers.

Where there is a will, there is a way. I understand what you said but don't quite get the concept.

No matter, I will figure it out if I do it myself.

I think you have done a great piece of Aussie innovation on that kayak and we would all appreciate pics or vids of your sailing adventures on it.

Looking forward to that.

you will need to-get fuel in...................... 10 min

Wow, that's impressive, can you post a pic of your car from behind burning rubber, or better still a video of the car flashing past the camera. Now that would be impressive

That's typical, from who else would you hear such a stupid and arrogant comment like that, history will back me up there. Most nationalities make products that are streets ahead of German products. Take cars: Mercedes for example are overpriced and overrated: I'd much prefer a Toyota (Lexus), Nissan Infinity) or Hyundai (Genesis), all are far better - and of course they are all reliable! And BMW, what a joke. They are fine. as long as you stay in close proximity to a mechanic.

Wooaaahhhh!
Thanks manfred, you are a real nice chap!

Well, l tried to appraise you workmanship on the sit on kayak, and if l, doing so, have done wrong, l am very sorry! l apologize!
Nevertheless, German design been pretty spot on in general in the last few hundred years. I used it as a measuring device, though if you resent my notion as arrogant or stupid, as l wrote, l am sorry.

The car - by the way is a Jaguar XK8 and the autobahn - or if this name causes unimaginable pain and suffering to you, like Dr.Goebbels's name to our parliament recently or the name like Mercedes let alone the quality of BMW, l am sorry - or freeway was in Croatia between Zagreb and Split.
Relax, have a beer! God forbid a German one, thou.

I must admit, I felt this post had a bit of negativity that is uncharacteristic of the Sailing forum, along with cisco's first post having a 'suck eggs' kind of air to it. I'm sure that wasn't the intent

Very nice work, Manfred. Having something compact and easy to pick up and carry around by one man is always a huge advantage when you head out by yourself for a day on the water.