LOVE that video - Nigel is a good surfer, he reminds me of one of my faves, Eli Mirandon! Man, what’s up with all the fin plugs!?
Good comment Moss, I was thinking something similar. Normally, when anyone starts talking math and forumlas on here, they lose me, maybe 'cuz to me it usually feels like they’re trying to ‘force-fit’ the math, and the justification/explanation ends up being a bit convoluted.
When I saw the board in the video, and listened to the explanation, I just didn’t feel the same about this. It seemed to me a legitimate avenue to pursue, and I’m guessing there is a related geometry in the physics of a breaking wave, so it does seem it might be a natural fit.
Having said that, I didn’t mean to imply that I really understand the method here, despite the elegant simplicity of the explanation on the video, but I’m interested in hearing more. Seems like someone could use google sketchup to illustrate or demonstrate the principles, then maybe I’d get it!
Thanks for the supportive comments and checking my youtube clip. I put that up last night.
Nigel is amazing, he borrowed a board from me and I thought he’d lost interest, didn’t hear from him for 6 months, then one day he turns up with lots of footage in great conditions. This was an experimental board. I have to reply quickly at the moment, but I put a lot of effort into fin positions and I want tranfer CAD drawings and explain them in detail. maybe put up another youtube clip on that topic. So what did I learn from that? 4 fins much better acceleration in a critical area compared to three fins. But different in the turns, the board automatically banks into the turns, pretty exciting. 5 fins and the board doesn’t bank into turns and it wants to flip over. 6 fins, harder to get going, but incredible at very sharp and quick turns. Feels like your actually turning backwards as you move forwards and handles steep parts of waves with ease, tends to slip into another track where you are only riding the three fins against the wave face. 6 fins done well is a serious option, might need to size fins, big at the front to smaller at the back. I tried the most forward plugs with three fins, So a stretched 5 fin option, it wanted to flip over all the time, but I grabbed the rail and pulled hard to fight against the flip and made an incredible tube, for me the longest beach break tube I have ever had, but much too hard to control. However in a tube, I think its faster than quad or tri. Conclusion, quad and tri fin stand out, 6 fin too weird to do commercially unless you make a special set of fins. I don’t think its commercially viable. 5 fins, only with a tiny fin at the tail. The most forward positions do something that gives you incredible acceleration in the barrell, but needs to be done completely differently to be viable … I don’t know what?
Thanks to all the people that are just looking, reading, 15 views on youtube over night. I appreciate it.
Hi Malaroo,
The clip was good, that board seems to go really well!
Having a background as a structural design drafty working on both structural and mechanical design I often think about putting some hard math into board design, just need to find the time to do it 
I’d like to experiment with the cissiod curve for rocker ( http://en.wikipedia.org/wiki/Cissoid_of_Diocles ), when the flatter part reaches a predetermined point, swap the curve to the tail and trim as required. This should give a perfect progressive curve through the whole board with enough flat in the middle to hold speed. May even work for plan shapes as well.
Anyway, very keen to hear your design thoughts, thanks for your contributions so far.
Cheers,
Mick.
Hi MickD
We are not far away from each other, I’m in Canberra, terrible place for a surfer to be, I lived at Bawley Point for the last 12 years and Avalon Sydney for 16 years before that. I checked out the Cissoid curves and the mathematical equations and my hair stood on end and my eyes went like big and round and blood shot. Very impressive, there are some incredibly clever people in the world. Since 1990 I have done 3d drawing on an engineering CAD/CAM pakage for CNC machines. You would understand what that means, for those who don’t know I will debunck the myth. Its Simple. To draw an elipse and cut it out involves the following.
Pick a co-ordinate, lets say the centre of the elipse is Zero in all axis xyz (talking millimeters here) so go point, keyboard, the xyz box comes up, go xoyozo, then choose draw elipse, box comes up, how long in x say x100 and how wide in y so say y50 hit enter, it draws an elpise. To cut the elipse, go to tool path, pick a tool size, click on elipse, the elipse is changed to another colour and the CAM side of things reads all the points that the elipse is made out of off. Send these cordinates to the CNC machine, put in a reset zero location to something such as x200y200z0 . Press go on the machine and it cuts it out. Done as quickly as you have read this note.
The other way to draw an elipse or any curve is to slice a cylinder, easy to draw on CAD, draw two circles the length of a board a part and link the two circles with a surface. Draw a line eaither side of the cylinder and link those lines with a surface. Click on surface intersect and the intersection line will appear. It would only take a bit of trial and error to find out if a straight line or and arc or a parabolic curve sliced through a cylinder would give a cissoid curve, this would then be called a malaroo cissoid curve … sorrry only joking. I’m a bit nutty and they can’t handle me here either laughing to myself at my own stupid jokes.
The CAD system you use if it has a 3D option will do this for you.
Before I came across my board design I was given the job making templates for RAW surfboards in Tathra. I was given a board that was ridden by Kia Otton and asked to do the measurements of the rocker and make templates. When I checked the co-ordinates and tried to find out what curves fitted exactly over the rocker curve the answer was part of a 7’6" elipse (on a 6’2" board) to the width of the board, can’ remember I think 18 and 1/2" (I’m writing this by memeory, its correct in concept form) but with nose and tail rockers lifting pulling away from the plain elipse about 6 to 8 inches away from the ends. I then tested this on other bopards and they were the same. When I made my boards some amazing things happened that made me think I had found somethiing special. You guessed it, the bottom curves pulled away from an elipse at the tail and nose. I couldnt believe it! Also the 3D surfboard shape (viewed from the top its a surfboard plan shape, viewed from the side its an elipse) rotated around the centre line, but viewed from the side gave the rocker shape and centreline plan shape and thicness when rotated to a quarter of the plan shape width. This made wonder, Whats that song “oooh it makes me wonder?” “Stairwaty to heaven” … Do I use the 3D plan shape for the rocker as well or use a simple Non surfboard shape for the rocker. I have used the actual 3D plan shape. Certainly fits the argument that the curves are related.
The advantage of slicing the cylunder is that not only will you be able to emmulate the cissoid curve you will also get a related plan shape and nose and tail lift.
If you try this and it works and you forget to tell me I will cry.
I hope my answer is usefull to you and others reading. Thanks for the interset.
Excellent! I tried something similar in google sketchup, but wasn't able to pull it off. It really gets the juices going, thinking about the possibilities, i.e. what if the cylinder was elliptical rather than circular in cross section! Infinite options. Really seems to geometrically define what shapers are already doing, but the potential for exploration / experimentation seems wide open. Thanks for the graphic!
Hi Moss;
I clicked on the link and had a quick read, I love that sort of thing, if I understood it better I’m sure there would be a way of using it. I’ll keep it in mind, really appreciate the reference. Something I have alaways wanted but never actually looked for. There was a special on the tele here about a week ago on that stuff and I forgot to watch. I dont thik I am in position to give it another go, but I figured I’d rather tell those who are interested just in case I die of bordom here in the country, then atleast someone keen might be able to benefit from my experience.
Hi Moss;
I checked out the link and had a read. I love that stuff, its something I have always wanted to know since being a kid but never chased it up. I’m sure it would be very usefull knowledge to apply eo surfboard design. Thanks for the refence, I really appreciate it. I don’ think I am in a position to try it again, thats why I have decided to go public with my experience, who knows I might die of bordom out here in the country and if that happened those who might benefit from my experience would miss out. I spent the last 30 years of my life working very hard and thoroughly at what I did only to loose everthing. This money thing and secrecy is not good for the human race and those who might benefit. Better that I share what I have to offer. Much more fun than chasing patents and trying to sell the idea and then working to make it profitable … I will have a look at Spence and 4est comments, haven’t seen them yet.
Hi Malaroo,
Yeah, that Power of Limits Books seems right down
the line of inquiry that you are following. What the check inside
example available on the site doesn’t show is all the examples of the
golden section that Doczi found in so many disparate manifestations:
musical harmonics, architecture, shells, skeletal and crustacean
exoskeletal forms, even the Boeing 747. For some reason this golden
section relationship recurs throughout nature and structural design and
has both profound functional and aesthetic effect.
Reading your
description of the ellipse experimentation on the CAD reminded me of the
examples of D’Arcy Wentworth Thompson essentially morphing the grids of
fish “designs”.
http://sinearch.com/wp-content/uploads/2011/11/Darcy-Thompson-mola-morph.gif
It
would seem a worthwhile direction in line with what you are doing.
Essentially mapping those same golden sections, the templates, and
changing the proportional ratios to meet certain conditions - different
waves (e.g. a more linear profile for slopey waves and more
curved/compact profile for punchier, more curvey waves.
I was
looking at some recent Matt Calvani shapes on the Bing website and
noticed the similarity of the “sweepea” to McCoy’s nuggets (at least in
terms of template).
http://www.bingsurf.com/surfboards_sweepea
Hmm…I wonder if those boards have a golden section inherent in them.
I’m
sure that Calvani is very familiar with McCoy, and Velzy, but it seems
that maybe he did actually arrive at this following the different
“evolutionary” line of the Simmons - coming to the same place from a
different direction.
I read somewhere else that animals have
evolved to essentially the same form to fill certain niches in their
environment. I think one of the examples is the Tasmanian wolf (a
marsupial) to fill the predatory niche that wolves and coyotes (canines)
fill elsewhere. It was the response to the conditions and function that
influenced the very divergent earlier predecessors to have an almost
identical final form.
Form follows niche, I guess. Should work the same for boards using geometric-influenced designs, too.
Anyway, that’s my blather on that.
Have fun, looks like a cool direction.
And hey, I think you can go back later and edit comments if you get multiple posts, just erase and put “duplicate post” in place of the earlier text.
a couple scientists
doin’ math ,in their lab
coats ,with the protected pockets…
Pythagrious was out at the time
so the boys got the pencil and
whipped up a couple templates.
The next day the geometric theorums
were proven,recorded,and drawn to scale
for sub two meter humans… they can be
so fun to watch,they try so hard.
…ambrose…
and the tall girls
think they are cute
Yup, never seen a chambered nautilus with a calculator, how does it know how to make that really cool shape? (The one the chambered nautilus chicks dig so much?)
Some experiments 
this only took 5 minutes but an interesting shape I think.
first shot is of rocker, side on to cylinder
next is plan on slice, perpendicular on rocker shot (true plan view)
last is of the cylinder after cutting 3d view
Yup, heaps of room for experiment. It’s good to beable to quantify things to some extent, I know every wave is different as is every surfer although I like the idea of tweaking the figures to suit these situations but still produce ‘true’ curves (for want of a better term).
Just to clarify the design above, the size of the board graphic is based on an elipse length of 6’ and width of 21", the elipse depth at centre is approx. 1/4 of the width to produce the rocker.
You can see the board is a bit shorter after cutting with the elipse so a bit of tweaking is needed but it’s early days yet 
Hey MickD you have done well, I’m chuckling to myself, to see someone sharing my adventure … is fantastic, You want to find the cissoid curve, hopefully we can do this and design a board accordingly. I’m happy to show you how to design a board, step by step.
The method we are using here will give us a cissoid with a 3D planshape curve as well. So cissoid curve through the cylinder as you have done should give us a 3D cissoid Malibu planshape. A few rules along the way that I will share with you as we go. I’m off to learn to draw a cissoid curve and … I’ll be BACK!
Cool, that would be good!
Huck’, I’ll have a go in sketchup and see what I come up with, if we can do it manually I can soon knock up a script to automate it based on typical input such as length, width etc, should be fun.
Your next step to get a more sensible plan shape is that the length of the eliptical line you have created is now longer than the 6’ board you started out making. Trim that eliptical curve to 6’ long, keep the flat end and cut the curved tip off.
That will probably surf quite well, but its in a different direction I have worked. The rocker of that method is double ended.
Try working with 1 quadrant of the elipse, You have 4 quadrants there.
I’m trying to transfer files from my CAD into the computer I am using, but its not working … very frustrating. I will get there, it worked recently.
By the way, how are you getting those pictures into text area?
