The WAVEWING hydrofoil (Florida style)

Hello,

I’ve been messing around for a number of years building different types of fins and such ,for swimming,and for use in the surf…

I’ve recently developed a paddle-in prone hydrofoil (planer).

I thought instead of posting just pictures, It would be interesting to some if I shared a little bit of the story of how they came to be…

I’ve been waiting trying to get some better video of my foil in better surf before I posted, but we are all so temporary here on this planet maybe now is better than later…

I can’t seem to link the you tube videos I have but I will work on it

 

     My foil in it's current form, is a progression of an Idea that began in the Florida Keys Where I grew up during the 70's and 80's,,Far from any rideable waves.

In my teen years we lived on a deep water canal that wasn’t open to the ocean.

I spent a lot of my summers spending as much time underwater as I could dodging jellyfish an snappers,I wanted to be a diver, or better yet a fish.I would often go to the bottom and swim as far and as fast as I could .

Once I even taped a little tire filler compressor to a garden hose in an attempt to breathe underwater,(it didn’t work, but I got a good lesson in physics as the air was almost instantly sucked out of my lungs lol)…

          We would also sometimes take turns being pulled behind a boat wearing snorkel gear holding on to a piece of plywood attached to a rope…The main reason for doing this was to locate coral heads for spearfishing…

The plywood acted as a wing and you could get out away from the boat to some degree, but I always wanted to go out farther and go faster underwater (There are now some commercially available products that do this quite well) …

              I moved inland after graduation and didn’t think about it much until around 2001, during a family dive trip back to the Keys I built my first wing…It was just a plain board cut into the shape of a milkbone, but it got me thinking about improvements…

It was during a dive on this same trip that I had a bit of trouble, I got caught down current from the boat and low on air, my legs were exhausted and it was clear that swimming was not going to work.

I went to the bottom and clawed my way back to the boat along the sand… I realized then how useless hands are for swimming with scuba gear and thought at the very least they could be used as directional “fins”…

I got to work as soon as I got home building prototypes using the pectoral fin of a porpoise as a model…

Testing them in the condo pool I realized It needed balance so I added a reciprocal fin and straps

This design hasn’t changed since then It puts the center of resistance right in the palm of the hand, as opposed to out on the fingers…

It also has very little drag when moved straight through the water. 

All of my fins and foils are designed with this characteristic in mind ,the amount of (thrust, force, resistance) can be changed by changing the attack angle…

I tried to see how big I could practically make them which led to designs such as this

This prototype would eventually be used as the shape for my first accidental surf foil…

I was surprised how much more power and control I had when I used them in conjunction with traditional fins.

It’s like having 4 wheel drive underwater. but they also work well above the water and it wasn’t long before I started using them in the surf here in Melbourne with my body board.

I developed the bomerang foil into a single piece handheld version using some carbon fiber scraps

The one on the lower right…

It was playing around with this in the pool where I could feel the difference in power and purchase when I grabbed the foil towards the outside of the fin forcing it into a concave shape on the downstroke,

compared to when I grabbed it in the middle allowing it to be convex on the downstroke…

Though grabbing in the middle seemed to generate more thrust.

 I tried to adapt it into a foot powered fin but I made it way too stiff and got nowhere fast(pun)…

There was also the “Turtle Belly” which was attached to a ski vest in an attempt to isolate the planing surface from the flotation (It did not work lol)

It was a continuation of that line of thought that led to the accidental creation of my hydrofoil.

At first my intent was to just to get some control surfaces down into the clean water, I wasn’t really trying to create a "hydrofoil ".

My intent was to build a body board biplane so to speak with extra surface area, some of which would stick out the side and protrude into the face of the wave.

I hoped this would give me a little more speed and hold in the face… But that’s not what happened,

The one on the left is the first foil.( the fins on the outside came later)…

It was made by laminating two of my much too large handfins together …

They’re flat, but I formed them into a concave when I laminated them together… I also tilted the center foil area up about 2 or 3 degrees relative to the main foil area to create a little lift in the front…

The first wave I caught I learned a lot… I caught the wave (maybe waist high Florida mush), and I was immediately lifted out of the water.

I tried turning and found myself fighting to get it to go where I wanted… It wanted to go straight and fast,really fast for the conditions…

It was also very difficult to keep the foil stuck into the side of the wave, it kept pushing me out and hauling ass down the face…but if I set the right line and leaned just the right way I could stay in it…

I  went home after about an hour and looked up surfing hydrofoils on the net… I saw pictures of (of course Laird), Terry Hendricks,Gilbert Lum, and Brett Curtis (Surffoils)… But no commercial foils, and none of the foils I saw looked much like mine,so I decided to keep trying.

I spent the next few months trying lots of ideas, adding fins of different shapes in a few locations to figure out what I could do to make it respond to rider input more like a traditional surfcraft…

These are a few of the things I tried to improve the performance before building  the new foil…

(Not all at once of course)

Through all of the fins and things that I put in different places on the foil I also concluded that the more complicated the shape is, the more unpredictable, or at least more turbulent the interaction with the water will be, So simpler is better…

My current foil is flat along a singular plane and curved accordingly where needed…

The ability to lean to turn and create hold in the face of the wave was solved by the adaptation of the parafoil shape combined with the small fins built into the outside of the foil…

Using the same logic I made the overall front profile of the foil into an arc to improve the foil’s ability to perform cutbacks more smoothly…

A true radius would work better, but an arc is a good compromise in both situations

The trailing edge before I added the tails was essentially the profile of a whale’s tail The foil performs fine without them but better with them…

The tails;

I added the flexible tails to the back in an attempt to add a degree of pitch stability without being so locked in to a particular direction…They interact with the rebound wave that comes off of the back of the foil…

The reason I turned them inwards at the center as it goes back is to cause them to flex outwards at the rear, creating sort of a channel effect while going straight,but because they flex, you don’t get the feeling of being on a track…

As you turn, the inside tail opens up more than the outside tail creating an alternate foil plane to turn against …

I’m pretty sure that they even provide some forward thrust as the upward draft of the rebound wave gets directed more rearward by the tail ( if you can imagine a split tail swim fin in the perpetual down stroke)…

The tails I am using now are recycled oversize handfins they are more stiff than desired and not quite the right shape but they’ll do for now.

The swept strut;

In addition to simplifying the overall flow of the craft and increasing maximum clearance from the water, the swept strut was built to act in a similar fashion to a skateboard truck.

It was designed so that when you lean on one side or the other the strut flexes and rotates into the turn,The harder you lean the more it turns, originally the strut ( as in this picture) was 1/4 x 4 flatbar with carbon uni epoxied to the sides…

I used uni to inhibit bending but still allow a lot of twist flex,I’ve now added some x 45 carbon mostly to keep the uni from coming apart…it has taken a lot of the flex out…

I still have some more testing to do to see if that’s a good thing or not…

I am now planning to expand my mold to build a lighter more streamlined foil I will post pics as I go…

 

 

Dave T.

 

Very nice Dave, the progression of your design is interesting.

Have you done any more work with your surfboard hydrofoil, the one with the carbon  re-enforced center track?

You should create a blog post of this development history …

Can you post a video of the foil in action of a surfboard?  Interesting design.

Wow!

so cool!

if you have the youtube links, reply w/ them here (just copy/paste the link) and we can make them work here. would love to see it in action

the pringle? the big wing reminds of this guy : )

Great creativity. Very interested to see where you take the design from here.

This is the url code for the latest attempt at making a video that demonstrates what the foil can do ( there are a few on my channel). 

I called it Florida style because it is capable of riding some pretty mushy crap

https://www.youtube.com/watch?v=qWelMK2vaf8

People have had more luck trying to film bigfoot than I’ve had getting decent footage on a nice wave,but I’ll keep trying.

Recently though I bolted a gopro on and did some filming in a pool which is also a part of the video…

The pool video(s) gives the best insight on how the whole thing really interacts with the water

With so many experts on water flow here on this forum, I hope they might be able to give me a little feedback on what they see going on…

Here’s a few pics of the shortboard conversion project that Stoneburner mentioned

      

   

I do have some ideas that might make it feasible to do a stand up version,

 For now though my main focus is on getting good photo documentation of bodyboard in action…  

 

In nothing waves, it is obvious you are getting lift.  It would be great to see what it can do in better surf.

Watching the flow over the wing makes me wonder if using ventricles across the leading edge would have an effect.  

AWESOME VIDEO! i’ve embedded it here so everyone can see it. SO COOL

Living in Florida, I can say if you are getting those kind of results in waves like that, you are really on to something. I don’t know how useful Swaylocks is going to be for you. You seem to be way ahead of anyone else. What you should do is look into NASA’s technology sharing program. They give entrepeneurs access to resources that can take you to the next level.

 

 

thanks for posting here again , wooddave

 

  these latest ones  certainly look blunter than the scary sharp ones you originally posted on 2ndlight.

 

  keep up the experimenting , mate .

 

And I can’t wait to see photos and footage of the surfboard version , in good waves !

 

 I had  the fortune of watching surffoils’ one , while I was in sydney ,  being ridden by Alex from here  [swaylocks]

 … maybe brett ‘surffoils’ / dr. hydrofoil will chime in here , with his photos of Al up and riding , on the hydrofoiled shortboard that Brett made ?

 

  cheers !

  ben

Thanks GORDOF for embedding the video, and the positive feedback…

 

gdaddy,

I think I know this, but what exactly are ventricles, and what effect do you think they might have ?

Right now the leading edge is foiled on the top but the other foil I had (It was lost during testing) was foiled on the bottom.

 I have been trying to decide which one is the most beneficial…

 

surfersensei,

Thanks for the tip on the technology sharing program, I will do some research into it…

and also thanks for the feedback. I’m sure though that there is plenty that I could learn from folks here on Swaylocks.

In fact it was my communication with Surffoils on a different forum that influenced the addition of the tails…

and it was only also after seeing his video and watching how his foil mount flexed that the idea of the swept strut came to mind…

 before that I thought because my foil is so wide that the loads would be too great to be supported by a single center mount…

That has made a huge difference in the performance…

 

Hi Fins,

I welcome any input or pictures from “dr. hydrofoil” haha

As I am doing the finish work on any of my fins or foils I always finish it to a fairly sharp edge then I blount it with 220 wet and a sanding block.

 I test it by hitting it with the back of my hand or fingers… 

 

 

 

I live in Merritt Island. I will be happy to test drive it for you if you want some feedback :slight_smile:

 

Once you figure out your wing building it out of a plywood and foiling that could yield some interesting flex.  I’ll bet a fatter dual foil  - like maybe 80/20 - out of balsa or paulonia could produce more lift with smaller dimensions.  I wonder where the point of diminsihing returns is WRT thickness and foil on a hydrofoil?  

 

I could see building a foil in two halves and then lamming them together like a centerfin.  Run them through a finbox and connect it to the deck instead of the bottom.  That would be wicked awesome.  

 

Where’s Roy’s tunnel fin when you need it?  

This is Dr. Hydrofoil… Dr Terry Hendricks from the USA.

 

 

 

 

 

 

 

 

 

 


“I live in Merritt Island. I will be happy to test drive it for you if you want some feedback :-)”

Definately surfersensei, I will PM you soon to work out details…

So far I’m the only one that’s ever ridden it.  

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“This is Dr. Hydrofoil… Dr Terry Hendricks from the USA.”

For some reason I don’t think Surffoils would disagree with you on that Ultimats…

He’ll just have to settle for being Captain Hydrofoil.

Which would make me Private Foil first class, I guess…

I would have loved to get DR.Hendricks opinion of my approach to foils.

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“Once you figure out your wing building it out of a plywood and foiling that could yield some interesting flex.  I’ll bet a fatter dual foil  - like maybe 80/20 - out of balsa or paulonia could produce more lift with smaller dimensions.  I wonder where the point of diminsihing returns is WRT thickness and foil on a hydrofoil?”

 You could certainly obtain more lift per sq cm of foil area by making it fatter and foiling it, but then it makes it much more difficult to paddle. Everything is a compromise…

I’ve tried to keep the foils as thin as possible… I want them to cut through the water like a (dull) knife.

Not only does it affect the paddleing but also while riding a wave at higher speeds a thinner foil will cut through a choppy surface and turbulence with less resistance resulting in a more manageable  ride…

I will use fiber orientation to obtain the flex that I need,but I have a beautiful piece of mottled makore veneer That will be vac bagged onto the top of one of the next foils…

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Monday I will cut the mdf for an addition to my mold that will enable me to build either a 26" wide foil or the current 32" wide, with the tails integrated.

Excellent! I look forward to it

. I will even let you ride my surfmat.

It’d be cool as hell to see how advanced surfers surf boards with this tech.  I know you know this.  Just stating the obvious.

Probably more than half of the people that post here would get a good sense of what’s going on with your inventing by just seeing someone surf a board with a hydrofoil installed.

Surfers love to surf new equipment!  I have no doubt anybody who surfs well in your area would be enthusiastic about trying a board with your set-up.