saw this on surfline and it caught my eye to bring to you all. the reviewer rips, no doubt. the board construction is interesting for sure, but is there any real merit to what is being said about flex and material properties and “bounce and snap off bottom turns” because of this construction? i’m not trying to take a dump on channel islands at all, i just have a hard time understanding how any of this flex or material properties discussed in the video is actually noticed. it’s like they’re talking about skis or snowboards, which can be significantly flexed by hand.
water is pushed out of the way easily enough and rails (that provide the “snap” in this video) are the most heavily glassed portion of boards and they’re thick. i haven’t touched these boards with my hands, so maybe you can bend them and flex them. i just tried to flex the noses of two of my shortboards by hand, figuring they’re the thinnest part of the board and should be flexible. i could hardly move them. how do these rails and boards bend and snap to the point of enhancing performance like the tester describes? i believe boards have the ability to flex across their entire length, but not by much, especially shortboards.
screenshot from a libtech/lost video. yes it’s a different, way more durable construction, but a truck is standing on the board and the nose isn’t even flexed flat. how is a power carve, in water, going to significantly bend anything in a glassed surfboard? full video here Could Your Surfboard Survive Getting Run Over By A Truck? | Teton Gravity Research - at 1:17, a surfer jumps on the board upside down on the ground. it flexes a little, but not much.
i don’t want to purely dismiss this as “marketing” - if there’s merit to the technology, cool. i just can’t feel any kind of flex in the boards sitting in my garage right now.
Have not viewed the video yet. But I plan to though.
Consider the following;
Surfboards experience 3 to 4 Gs in hard bottom turns. For a 16o-lb surfer, that would be the equivalent of 480 lb to 640 lb on top of the board (during these turns).
If a tire’s inflation is 32 psi, that is the force exerted on the surfboard’s surface per square inch of tire contact patch with the board (think minimum compressive strength) – a deceptive advertising ploy (?).
I defer to George Gall’s/PlusOneShaper’s – engineer and mathematician surfboard builder – discussion about flex at the following links (last half of first link and first half of the second link):
morey and greenough defined everything we need to know about flex
if we want to really experience the benefits of true flex then all we need to do is ride a boogie board or a mat
those are the only two water craft that truly take advantage of flex
the so called “snap back” is questionable in how much it makes one a better surfer
but to morph the actual shape of your wave riding apparatus according to your needs
well the boogie and the mat have shown us what that can do.
Complete and utter bullshit,
I would have to re-watch it a few times and REALLY try hard to find a statement that is technically accurate from a composites engineering perspective.
for flexural deformation you must have flexural momentum= forces x distance between opposite forces. Because surfer push on board with feet and water push under board under feet, distance is miniminal so flexural momentum is minimal, far less than the upside down flex test on floor. So you are right if you want a significant flex you need a really flexible build, look at pendoflex flex tail for exemple. Plus if board increase significantly under feet, Rocker increase in turn would push so much water that board bog. Prone bodyboard work differently, they are flat and rider flex then between arm and body to turn. That’s way prone riding on surf is not effective. Surfboard flex have an impact on vibration aspect = stiffness feeling. On the lib flex bus board take more or less 1/4 of truck weight when one wheel is over.
Looks like a variation of things done before. Warvel’s WMD blanks had EPS with perimeter stringers and a band of PU.
George Gall did something with Maurice Cole cutting sections of EPS foam and inserting Carbon Fiber. The cuts were similar to the boards in the video.
Seeing a lot of creative ideas to sell boards. The CI flexbar and X-int tech caught my eye when we were looking at boards in San Diego. I wonder what people think of the Incide blanks from Dan Mann and US blanks.
In my opinion based on blind testing by good surfers who did not know exactly what they were riding, flex is not bs, and can impact the handling of a surfboard in positive ways. That being said flex is not simple to dial in. But it is a frontier still, despite the work that has gone into it in the past.
With bodyboards and mats you have weight distribution pretty much over the whole board. The rider can effect the flex by shifting his body or using his hands and legs to flex the Board or mat. Both will more or less flex to the shape of the wave. One of the complaints you hear about Eps/Epoxy is that the boards have more vibration,chatter. Engineers and scientists have spent years working with every manner of materials and combinations of materials to Car makers want stiffer frames and bodies to get better preforming cars while still damping the ride with a better suspension system. Arospace engineers have to get wings and boadies of all manor of aircraft to take the stress of flight. The tips of the wings of aB52 bomber would touch the ground if not supported. The body of a 747 Jetliner at altitude can expand by several feet.
Marine Architects seek that balance of stiff hull that can still deliver a comfortable ride. Same holds true for skis snowboards and even golf clubs. Surfboards have until the last 10 years or so have been far behind in this quest of improving performance the boards preformance with how they are built. The shape of the board. The shape of the board seems to be the first thing that is looked at to get a different ride out of the board. Now we are just at the beginning of looking at how and with what is used to build the board will effect how that board will ride. Is this CI build agame changer? Not sure it is others are also looking at ways to take some of the chatter out of the EPS/Epoxy build and still keep some of the flex in the board. Duel core blanked with flex ratings and damping might be the future.
Some of this will be just hype. Some will have some validation. The big board builders are looking for somethin? Lookingfor anything to sell more boards. New models with new improved widget seems to be their answer. A lot of the surfers out there seem to buy into the new and improved. Even if it doesn’t improve their own Surfing. Shaving a couple of pounds off a board then putting 1/4 lbs traction pad on with more weight from solid glass Fins just seems odd to me to be counter productive. Some good will come out of this I’m sure but keeping a sharp eye out for the hype.
thanks for all the responses everyone. it’s really interesting to me. the boogie/mat comparison is helpful too. boogie specifically has visible, impressionable flex that i can see. maybe they don’t spring or snap back much, but they’re visible. i understand damping qualities of the materials/foam types as being applicable for sure, too. if it’s all about the damping properties of foam/materials and not the actual flex, i think problem is the use of the wrong labels by the marketers. i totally understand PU having a more damped or shock-absorbing feel than EPS. that’s different than flex, eh?
That was a few years ago and the results were supposed to be made public, as he asked for money on Swaylocks to help the project (and I gave 30$ and feel these were stolen from me considering everything went silent afterwards).
This project was really interesting and would help answer the question. I think more and more that the so called flex is more about dampening and vibration properties giving a crisper or a more confortale ride depending on the vibration level.
Watched both videos.
First video had lots of generalities. My favorite statement, “The EPS core is more buoyant.” (Which weighs more? A pound of feathers or a pound of lead?“) Buoyancy is about density.
Second video, note they drive over the board with the truck’s rear wheel – most of the truck’s weight is over the front wheels. Again, the tire pressure determines the contact patch and how much force is distributed per square inch of the surfboard’s surface (psi, pounds per square inch).
Finally, thickness significantly affects flex (“stiffness”). How thick is the board demonstrated?
I had a 1980, 7’6” Morey Doyle closed cell foam, soft board (polypropylene/ehtylene and eva?). The flex was clearly noticeable and I liked it (fun).
The Hvac aluminum tape with the peel off backing, placed on the hull of a board, since it cannot stretch or flex, should break when the board flexes, and those breaks should reveal where the flexing is occurring, and perhaps the amount of flex can be inferred by how close the breaks are. I’ve not tried it though.
From my limited viewpoint, I am interested where this engineered or happenstance flex goes, but I am not so interested in it on my personal boards. I feel flex = soft and squishy in a hard turn, and any rebound/twang merely adds an unpredictable factor, and i do not care to try and surf according to what the top 32 get judged for, and I have never made a cent in the surfboard industry, and never will.
Marketing, in this day and age, disgusts me. A necessary evil perhaps but mostly it is legal dishonesty/trickery to separate a consumer from their money.
I agree with Keith. Surfboard flex is real, and how the board flexes is a critical characteristic top level pros look at. That’s a big reason they don’t jump on new tech quickly, the flex is not the same as what they are used to. Problem with the pro board is that it is made so light it doesn’t last long. That light weight build gives the board extra flex, making it hard to match in a durable board.
When I look at the modern tech/new materials, I look at the costs and what they add to a board.
I think Stretch has figured out the easiest way to manage flex, use rail channels. No complicated blanks to make. There are several builders doing that now and they’ve figured out how the shape, length and depth affect the flex. I also like the way they add a lot of strength to the deck, and help the board from buckling.
do you think it’s actual board flex or the damping characteristics of the materials? i noticed the commentators of the trestles contest earlier this month were commenting on the # of surfers on epoxy/eps boards. that it was surprising to see so many but that they’d figured out how to keep the chatter down w/ the materials. (they kept calling them “eps glassed boards” LOL
again, thanks all for the input. this is fun to discuss!
I’d say the board flexes, there’s a springy effect that you use. It may be very subtle, but it’s there. I also think there are advantages of EPS/Epoxy for weight and thickness, so the pros can probably go thinner than a PU board and get even more flex. As far as dampening, I can’t say. I’m pretty sure the top level shaper/builders have the EPS/Epoxy build figured out, so they can make boards their team riders will like. I don’t know whether it’s easier, faster or cheaper for the big names to work with EPS/Epoxy or PU/PE. If it isn’t, then the move to EPS is for performance reasons.
If you’ve ever ridden both the fiberglass, and then the toughlite versions of the same board, you would know that flex is very real, and not just for dampening chatter.
and the purpose of flex is…?
what?
how is it better?
Does it make me a better surfer?
Does it makes my board last longer?
why do I need it?
I don’t think that’s been answered truthfully
I’ve ridden them all
doyle
surftech
firewire
surflight
coil
home made Bert Burger 1.75" thick x 25" wide magic carpet
baords with springers
boards with perimeter stringers
old board tech
new board tech
even body surfed when I was young
My geminis and multi fin griffins
using different a completely opposite tech strategy
still one on one surf way better
its all become like
golfing, ski’s and mobile phones
what do you really need
versus
what they want to make you think you need
