Tuna Swirls

Interesting to see someone understanding some of the benefits of flex. From the flexspoon perspective this is applying flex in a much too limited way to the wrong vehicle.

Here is the article that Mark Rabbidge wrote that appeared in Austtralian Longboarding.

"FLEX IS IMPERATIVE in any design since boards started flexing way back in the days of the vee bottoms. It began with the stringerless boards with big flexing fins on them. That whole sensation of being able to store energy removed us from the dis-placement boards, which were stiff, and on which you actually surfed on the surfboard, on the wave. With flex, you start to become part of the wave because your board's flexing moves you into different parts of the wave, it allows you to fit better into the wave.

"The energy store then is like a whip effect. As you put the power on, and release your body, the fin and board releases as well.

"I'm not a fan of the rigid style of fin ... 1 think it's something that has come into design through shortboard surfing, a lot of those guys go with very rigid fins. But 1 personally don't think that adapts into longboards. 1 think high-performance longboards have a lot to do with flex. Then, in bigger waves, they don't cavitate, they don't jump out of the water, they're not affected by chop as much, they just fit in better. They're more forgiving.

"This board has three flexes. The whole board flexes throughout its length, that's paramount with all my boards - my personal boards flex more than the ones that 1 sell. When you turn it, the whole board bends, and then it straightens out giving you a slight whipping effect.

"The second factor then is to make the tail flex that little bit more - the tail tweak flex adds even more flex. It gives you more tail lift,as you turn, so it short-ens the curve on the bottom curve. which adds tail lift. That decreases the size of the turning arc. Then, as it releases out, it gives you the whip.

" I've found that you get to a stage where the fins start fighting that process, as they're too rigid, so the only way to expand on the concept is to work on the fins. 1 started with the main fin and ended up with the side fins. 1 didn't just go hack, hack, hack, this is it. 1 tried the main fin first, then when 1 found that worked 1 tried the side fins, and found it all worked bet-ter. That's as far as I've taken 'til now. The next step is to surf it in all conditions, and put it out there, get guys riding it. So far, in good waves, bumpy, choppy, it goes sensational.

"Flex has been around for a long time. 1 can remember guys talking about dolphin tails and other marine creatures, applying them to surfboards. Any designer who knows anything about foils in the marine situation understands that they not dealing with anything rigid, with anything that's static. Everything is moving. Your foil is in a wave, and in a bottom turn you're going through four or five or umpteen different foil changes. So to have a board that flexes enough to fit some of those wave contours better has to provide a better response, it must be faster. lt's fitting the wave, it's not fight-ing the wave.

To go back to the beginnings of the flex thing, 1 remember riding an old Scott Dillon with a big flexible fin in maybe 1966, and 1 had to have one ... and then think of Greenough changing his inflatable mat to fit into a part of the wave. Mitchell Rae has been synonymous with the whole flextail concept, and some of his stuff has been brilliant. And he hasn't really gotten the credit for what he's done.

"Surfboards are the only piece of sporting technology that hasn't changed in 40 years. That is, a piece of foam, with a piece of wood down the middle of it ... a piece of wood! Golf clubs aren't still made with hickory shafts, they're got the latest titanium, and carbon fibres ... a tennis racquet isn't still made of wood ... what they're all about is controlled flex, controlled response.

1f a surfer wants to experiment with flex they can do so on their own board. Start with either sanding the fins, or ideally, cutting slots in the back of them. That gives you controlled flex. It's just a matter of putting a pencil line around the high part of the foil, say 1" back from the leading edge, and cutting some slots to that point. If you've got side fins, you could even start with just doing them. Then put standard rigid fins back in, and feel the difference. But don't compare it to how it used to go, try and feel what you can do on the board to improve the way you were rid-ing. Find where it will put you in the wave. Then if you want to go the next step, do the main fin and end up working on the board itself.

1t's a matter of templating the tail plan shape, moving it up the board some 10Omm, reproducing it, marking it on, then grinding out the fibreglass and foam from the deck down, leaving the bottom layer of fibreglass. You don't even have to go right to the glass, just leave a thin layer there that will flex, and reglass it all. Bingo, you've got a flextail.

"The next thing for me will be to put carbon fibre in my fins, and also in the tail of the board, which will allow it all to respond quicker, as the carbon fibre has a better 'memory', that is, it goes back to its original shape quicker.

"Longboards went better when flex was first used on them, they went dynamically better, and nothing's changed. They still go better with flex!" - Mark Rabbidge, Retro Surfboards .