Is this Australia's first Kayak Wingsail?

[goanywhere]

I am looking into finding out whether it is possible to get an inflatable pocket made by someone. It shouldn't be too hard but I haven't spoken to the guys at the local Clark Rubber store. If that's possible it should be fairly easy to make a collapsible one. I'll put up a post if I come up with anything. Good luck with the build, I am happy to help if you get stuck.

[emufingers]

Hi Steve, You can get polyethylene tubing which is about the right width for you sail. Get it from landscape supplied or hardware stores. I use it for vaccuum bagging fibreglass. You can weld the ends using an ordinary household iron with paper to stop it from sticking to the plastic. I can even give you a template for the ends so you have an aerodynamic shape although I suspect you outer cloth would already do that. Ask for tree guard polyethylene.

J

[andybear]

Wow!

Very impressive bit of work there, thanks for posting.
I was wondering if an inflatable core shape would be an option, perhaps space saving for storage.

I love your work, Cheers andybear

[goanywhere]

Hi Steve, You can get polyethylene tubing which is about the right width for you sail. Get it from landscape supplied or hardware stores. I use it for vaccuum bagging fibreglass. You can weld the ends using an ordinary household iron with paper to stop it from sticking to the plastic. I can even give you a template for the ends so you have an aerodynamic shape although I suspect you outer cloth would already do that. Ask for tree guard polyethylene.

J

Thanks Jerry, good to hear from you. I will look into that. I actually want a 'pillow' shape rather than a round tube, but if your suggestion of using an iron works I can easily flatten the edges to force a sharper profile. I'll let you know how I go.

I am sending you a PM.

[PeterJ]

great work, I saw a bloke at mallacoota that had something like that on his canoe last year, it was made from the plastic sign board.
Great to see new things on the go.
If youve seen how fast the Americas cup boats sail with the wings its the way of the future.

i have a wing nearly 8 ft long made from the plastic stuff here, maybe i should convert it

[goanywhere]

Hi PeterJ, yes, plastic corflute could be used to make a rigid wingsail very easily. It would need something to form it into a wing profile, and some reinforcing to prevent it from bending out of shape but the idea is brilliant.

Could you post a pic of your wing? What was it from?

[PeterJ]

the wing is dead now.
It was made from 4 mm flute and was copied from this tutorial on how to build them.
Here is a simple wing making tut
http://www.spadtothebone.com/SPAD/FNSwing/ another http://www.spadcombat.co.uk/spad/index.php?option=com_content&task=view&id=28&Itemid=42
They used CA ( super glue) i used contact cement and it held super strong.

For what they are they turn out incredibly strong and very very light. I guess if you could change the angle of the lift surface with a trailing edge of some sort it may work. As we know , a normally designed wing has lift in effectively one direction so you'd need to make it work equally well on both sides because there would be no way to flip the wing over to the other side. A symmetrical wing ( same shape and distance on both sides) could generate lift with the use of the angle of attack to the wind or flaps that extend one side and create lift (vacuum/ low pressure) on either side when needed.

I guess this explains a bit with a symmetrical wing and how flaps help to create lift. I think that's the system big yachts use to control the sails/wings, but then it starts to get all technical with controlling the flaps.
http://www.dynamicscience.com.au/tester/solutions/flight/wing2.htm

[goanywhere]

Yes, that is a big issue with rigid wing sails. The big yachts use a hydraulically adjusted leading edge section that is curved to create the flatter surface on the leeward side that is not practical for a small boat. A flexible trailing edge can be a solution but it might be difficult with corflute board. Maybe a fabric trailing edge might work though.

[emufingers]

Good to see you are back. I found this while you were away. Your yak would never touch the water.

http://www.macquarie.com.au/mgl/au/speedsailing/design

Jerry

[goanywhere]

Hahaha! Yes, and for a fishing kayak you could troll fast enough that by the time the fish catch the lure they will be so tired they won't be able to fight!

I have been working on the collapsible sail concept while I have been away. I look forward to catching up with you to chew over some ideas.

Interested in collaborating on this one? We might become millionaires if we can crack a practical design

[emufingers]

Hahaha! Yes, and for a fishing kayak you could troll fast enough that by the time the fish catch the lure they will be so tired they won't be able to fight!

I have been working on the collapsible sail concept while I have been away. I look forward to catching up with you to chew over some ideas.

Interested in collaborating on this one? We might become millionaires if we can crack a practical design

Yes as you know I am into aerodynamics. I have been chasing up some ideas.

jerry

[RangiRocks]

Good for flying fish perhaps

[bitisbitis]

Very intresting discussion. While I was reading this it took me back a couple of months to when I built a electrical plane from scratch to fly around the park. Creating lift from a flat structure etc. have you guys considered using servos in your "sail" to change the angle of the trailing edge if required, the same as you would regulate ailerons or flaps.
Cheers

[emufingers]

Servos are fine for model aircraft and are use as sail winches on model yachts. The forces on larger sails mean large expensive servos and hefty batteries. Thinking more of using mechanical advantage using pulley blocks. Servos and water are a difficult combination, ask the model yacht sailors. The main supply is fine but keeping the signal clean fir control is a nightmare. I'm just starting on the force calculations if my rusty maths will let me.

[bitisbitis]

Hmmm, not so sure about that, if you consider the servos used on a 3D model plane, running a 150cc petrol motor.... Pulling huge forces on the wings etc. Might be expensive but model plane servos I think would do the trick.. There are many RC servos that can do 24.5kg - cm. Anyway just a thought.