Guys a few months ago the fist images from Hydroflex started to appear, things are starting to move forward and manufacturing has begun in Oceanside, Ca. They are glassing and making this technology to shapers who are looking to spice up there offering with the latest in high-tech construction. Give them a call you will be blown away.
Take a look at the site http://www.hydroflex-surfboards.com/hydroflex-technology/index.php
I will post up pics of new boards as they come.
boards and tech look pretty interesting.
but, i'm kinda hung up on this quote from the website:
"We developed the very first flexible stringerless surfboard in 1998."
really? the first? nobody before 1998 made a stringerless surfboard that flexed?
sounds suspect to me. if you guys have something good going,
don't bring yourselves down with false claims...
just my opinion.
**The optimal application of internal force vectors guarantees maximal reset momentum **
I hope no one is upset about the quote. Sometimes the translation from German to English is misinterpreted. It should read that Bufo has been exclusively designing stringer less surfboards since 1998. He does not claim to have invented the stringer less board. I will have someone work on the site…. and re-word the statement…
i had a feeling your meaning might have been "lost in translation"...
again, you guys have some nice looking boards and, the tech is very interesting.
big name shapers too. good luck! i remember that video with Bufo bouncing up and
down on one of his boards. incredible!
I still want to see a video of one of these boards sitting on shapers racks with 100lbs resting in the middle, and watch the board stiffen/relax as it is pressurized. Until then I am convinced the whole variable flex thing is pretty much a gimick. Or you could let me ride one…
We would love you to ride one. The board is not a rubber and doesn’t have a limp rocker. When the board is inflated it is noticeably stiffer. The rail line and rocker are constant and will not bow when pressure is added. The stiffness is achieved through tension. I know it is hard for most people to except the concept. I too thought it was a joke, but riding one has changed everything for me.
What type of board do you ride; I am sure we can get one for you to try. I would love your feedback.
I have some Mayhems and boards from a few top international shapers that are for the trying. We will have some long boards available soon. Please feel free
I personally have a few Robert Wieners” Black Diamonds” coming you are welcome to give it a go.
Please take the offering serious, I am sure you will be impressed.
Clark
I thought "SuperChargers" were little canard type fins from Herb....
but the blow-up board is funky too.
Just a quick link of what the guys at Nirvana are saying about Hydroflex.
http://nirvanasurfboards.blogspot.com/2010/02/hydroflex-is-coming-to-nirvana.html
A Pic of a New Donald Takayama
A Rocket:
Adjustable flex is a great idea. Could you demonstrate this variable flex in a youtube video? Just like Durbs said, put a weight on it, pressurize the board, and we should see the board un-sag.
Alternatively, run the test in link below at the three pressure levels you recommend:
http://www2.swaylocks.com/forums/hard-numbers-flex-demystify-flex-patterns
Either of these tests would take 5 mins to do and 5 mins to upload on youtube. And then you would unequivocally be the first guys to manufacture adjustable flex. If a third party would help legitimize the concept, I’d be happy to run flex tests for you, and post a video.
Whether it works in the water is a whole other story. Any demos in San Diego?
Ben-jah-mon… I love your thinking. I am, as usual, standing by…
The claims on the hydroflex website got me wondering who actually made the very first flexible stringerless surfboard?
With a EPS foam core that allow air to be distributed to form an even pressure (without blowing out the glass around the vent), doesn’t that indicate that there is voids between the closed cell beads which seems to me would be likely to take in water when you get a ding? At least you have a vent to hopefully be able to blow out the water afterward. I thought that bufo did not use EPS before, there were some interview where it was stated that he used some unique foam made by VW for impact protection? If it’s straight not so well fused EPS, why do you need the deep penetrating 3d roots for the laminate? Delamination on EPS boards is not a big issue unless you leave it in a hot car.
Benjamin, if you could run a test on a hydraflex (or someone else for that matter) and it actually do alter flex significantly by pressure (which I very much doubt I might add), wouldn’t that indicate that the compression of the core play a significant role on the flex of a board?
Haavard,
Without knowing the precise details of the construction, it’s difficult to make any remark on…oh wait! they said it’s patented, so the details should be on Google Patents. When I have time, I will look at it.
Funny, my students just took their midterm on pressure vessels. Here’s the midterm solution:
http://maecourses.ucsd.edu/mae131b/Midterm1_2.JPG
Here’s a crash course simplification for a surfboard application:
2)take the greatest thickness of board: d=2.5"
3)take the thickness of the laminate(only the glass and resin, ignore high density foam): t=.03"
4)take the pressure: P=6psi
5)longitudinal stress at thickest point of stringer=Pd/(2t)=62.5/.06=250psi (this is an upper bound)
So lets assume the pump adds 250psi stress to the laminate. That’s kinda impressive considering 6psi is only about 40% more than atmospheric pressure(1atm=14psi (6/14=.4)…you couldn’t drive a car or ride a bike with tires that have only 6psi in them. Laminates break at around about 50,000psi. While you are riding the board, laminates are probably regularly experiencing 10,000psi in stress. I’m spittin this out, so if there is a mistake somewhere, please let me know.
The 250 psi is tensile…when you tighten a guitar string, what happens? The pitch gets higher…higher natural frequency. You can actually see this with a rubber band. The more tension, the faster it vibrates. So adding tension will make the board recoil faster. Will it also bend less? No! The rocker deflection should be the same at any pressure level. Can’t think of an at home demonstration for that one. This a dynamic stability problem–the calcs are heavy.
This whole rant is a drastic simplification, but assuming the entire surfboard is a pressure vessel and that pressure is diffused evenly in and out of foam cells, the following statements should somewhat accurately describe the board’s behavior:
1)The board doesn’t have adjustable flex
2)The board has adustable recoil rate
3)The adjustment of recoil rate could not be changed by more than 5%…probably closer to 1%
I’m not bashing or endorsing. I have a lot of respect for anybody who is doing something new and creative.
How can I demo a board in San Diego?
I really like your skepticism Ben… and i agree with you.
Does adjusting the air pressure inside one of these boards effect vibration damping more than anything else??? If the claims are true about these and a difference in ride is felt, yet the test Ive proposed yields no difference in deflection (as Clark claims) this must be it… The test I propsed is static, yet the boards response in surfing is dynamic.
Clark: If you can get a board up to Goleta (Santa Barbara) I will gladly ride it, pass it around to my friends, play with the pressurizations and post an unbiased and honest review. The waves around here are generally pretty small and gutless, I usually try to ride a board around 5’10 x 19.5" x 2 3/8". I’d like to try one of the black diamonds if I could… but whatever I can get my hands on I will have fun on for sure.
in the most recent Surfer's Journal, inside front cover.
there is a pic of Mike Doyle with a hollow wood paddle board that he says you adjusted the
air pressure in to change the bottom contour... i'll post up the full caption when i get home.
I can only find one patent in Bufo’s name (Rouven Brauers)
It seems to me that the construction method described is pretty standard glassing with laps.
They seem to be claiming that the inventive process is the fact that they using a stringerless, closed cell, blank with epoxy resin.
It appears they are claiming that before they invented this process (patent date is 2003) , stringerless epoxy resin surfboards were only made in moulds in two halves(pop-outs).
.
The only other one i can find is NOT a patent, it is a patent application.
http://www.google.com/patents/about?id=C4CYAAAAEBAJ&dq=rouven+Brauers
This seems to be an application for a patent for the procedure of altering the foam surface with grooves & indentations
and then applying an intermediate layer of resin/cloth to stengthen the bond to the foam, and also for a production method of composites to produce a rough surface finish.
It seems to be very broad, covering many types of foam and grooving/indentation methods.
.
I can’t find any patent regarding the inflation/valve aspect.
On the website is says Hydroflex is protected by 3 patents, but does not give details. I wonder what they are?
(Not a big fan of patents in general, I can see in some cases they are neccessary, but most of the time the only winners seem to be the lawyers!)
"Three way hyper alloy combat flex chassis that resistant to mutant stress fracturing along the diagonal hyperbol titanium sleeve. Combined with the roller cambered archive adjustment valve and you have one hell of a surfamabord".
-Resinhead, Swaylocks 2010
Here’s my thinking (and please correct me if I’m wrong, which is quite frankly very likely…)
Here is a simplified representation of a longitudional slice, two piece of 3mm balsa taped together to form a deck and a bottom with a rocker. Endpoints are fixed together just like in a surfboard.
Here is the same one just flexed a bit
Note the thickness change. This makes me believe that my core is under compression. Now this core is air and have zero pressure resistance. However, the lightest construction grade EPS (approx. 16g/l) from one of the local manufacturers is rated at 60 kPa(or ~9psi) short time load (10% deformation) which is pretty low. I have a sample of 18g/l EPP which is extremely soft, maybe 1/3 of the lightest EPS. Now I don’t know how to calculate the load on the core from the flex load on the laminate/skin (and I do think that a computer model might be in order due to the surface curves), but it looks to me like the flex would depend on how much the core compresses (ie. the load required to flex the above example would increase if you filled the gap with a sponge (like low density EPS), an inflated baloon or a higher density material). As I think i’ve mentioned before, this is about as much a non ideal core material as it get’s thus I would think that a few of the typical formulas for calculating the stiffness of a panel/beam/whatever is no longer good as, for one thing, they usually depend on the thickness being constant and not dependent on the load.
And if the flex of a board is indeed dependent on the compression resistance of the core, then altering the compression resistance by increasing internal pressure may increase the stiffness of the board. Given the above rating of lightweight EPS, 10psi seems quite significant?
regards,
Håvard
GOLD !!!
Cheers
Mooneemick
haavard,
On a real board, the rail and foam enforce compatability between the top and bottom skin. While the stiffness of the foam and rail is small compared to the stiffness of the skin, it is enough to ensure that the deflection of the top skin is the same as the deflection of the bottom skin. So I would have to say that your model is not accurate.
Also, you can’t compare the strength of the foam to the pressure of vessel. While the foam could be as low as 10psi strength, the stiffness of the foam is orders of magnitude stiffer than air at 6psi. Push your thumb into a tire with 10psi pressure and you’ll see that it deflects without limit. Then push your thumb into 10psi foam, it will deflect a tiny bit, and you had to push much harder. Stiffness not strength will determine how the top and bottom skins will stay separated.
Also, because you are pushing on the ends(longitudinally), you are bending the beam through destabalization(buckling). Surfboards normally are bent by transverse forces not longitudinal.
Here’s an interesting test: take one balsa plank. Restrain it at two ends so that the plank is neither in tension or compression. Have the plank oriented just like in your picture, not laying on the ground. Tap it horizontally and watch it resonate horizontally. Then put it in tension and tap it. You’ll see the resonant frequency go faster. Now put it in slight compression before it bows(buckles). You’ll see the res freq. slow down. Continue to add more compression on the ends to until it bows just like in your picture. You’ll see the res. freq start to speed up again. Interesting! Tension increases nat freq, Compression can increase or decrease nat freq depending on the magnitude of the compressive force.
Personally, I think that being able to adjust the natural frequency of a surfboard is totally awesome. Being able to adjust the flex/deflection of the board would also be awesome, but to do so you would need to change the geometry of the structure and/or the material properties of the structure. In my experience, I have never seen a structure become more or less flexible by changing the loading conditions (adding pressure, pre or post-tensioning…) UNLESS, the loading condition changed the geometry or moved the material in the post-elastic stage. Sometimes we design pre or post-tensioned concrete to crack, in other words the structural advantages become apparent once the concrete cracks(goes to the post-elastic stage).
Hydroflex says that pressure does not change the geometry of the structure, the shape of the board remains the same. But maybe it actually does. They recommend adding more pressure for glassy surf. If there is significant concave, the pressure would definitely reduce the concavity. As the bottom skin moves farther from the top skin, the board would become stiffer AND the recoil rate would be faster. This loss of concavity may not be a bad thing in glassy surf. In my experience, concavity was most beneficial in choppy surf.
I can’t wait to get my hands on one of these things. Tired of talking about it.
