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I really hope at some stage someone does this.

Id really love to see a independent test done by a surf mag or something where they get exactly the same shapes done in different PU/PE foam density and glass schedule and then the same in half a dozen EPS Epoxy constructions, have all the boards painted (over the glass), same fins same deck grip wax everything and the get half a dozen surfers, say two pros, two decent surfers, and two very average surfers. (say two PU/PE boards and six EPS/Epoxy boards)

Do it somewhere like Mentawais and after say three waves they paddle back to the boat and get asked how the board went and what board they thought the construction was.

It would be super interesting.

Id be putting my money on it that most could pick the EPS/Epoxy composite constructions, but not some of the non composite type EPS/Epoxy boards.

IMHO a lot of it is (i think the word is) cognitive bias, a huge part of surfing is in the mind in so many different ways.

I don’t get it why some people get stuck on calling FW build X the same as Pu/Pe.

It’s not the same and thus won’t behave the same. There’s a spring and there’s a damper. You can aim to tune them to be like one another but ultimately they won’t be 100% of the time. Vibrations (the type of dynamic physics) are tricky like that. Resonance and natural frequencies will shift for a board with the otherwise same cut.


a spring and damper model, for example


And yes it can be easy enough to feel. Maybe when paddling around, maybe when paddling in, maybe when surfing or some aspect of surfing. Designers can tune their constructions to feel similar while surfing, or while paddling around or maybe a happy medium for both. But, to claim they’re identical in all conditions is a joke.

They’re going to behave differently because they are different. But, it doesn’t mean you’re wrong for liking it.

Anyone else see the Stretch hand shape on IG? Pipe board. Made it with Clark foam and even mentioned it was Pu for damping characteristics which are different than his EPS. Heh.

everyday PU shortboard blanks about 2.2 lb/cubic ft (pcf). Superlight team PU close to 2 pcf.


Wall insulation EPS from Home Depot is 1.0 pcf. This can't handle much compression Vacuum pressure https://www.swaylocks.com/comment/94770#comment-94770

I found about half what the manufacturer said here https://www.insulfoam.com/wp-content/uploads/2014/04/12001-Wall-TDS_WEB-REV8-16.pdf

However I encapsulated it in super strong divinycell or corecell sandwich and obtained a light bullet proof build.


So FW's Helium of 0.8 pcf is extremely light. Which as I said leaves plenty of room in the weight budget for a super strong sandwich, however they compromised a bit and went for a superlight build. On paper should still be strong though.


So on to your question of Styrofoam cup and cooler - wild guess just from looking at the bead size maybe 1.5

Strongest builds are very light EPS and heavy/solid sandwich skin. HS say they use a hi density EPS for their futureflex build. They don't say exactly what, but if it is something like 2.0 then it is not possible to produce a bullet proof build. When I enquired about futureflex on my Chilli thread Hopeless and Havoc said something to the effect of rides decent, not bullet proof.


It looks like the new build (surftech/cobra/domestic) is going to follow the same paradigm. From a couple of days ago - new rail tape, so same rail stringer methodology.

View this post on Instagram

our first custom of the year is brand new edition of @haydenshapes FutureFlex Carbon tape. We’ve done quite a few over the years but this is the first one that has been tested and refined in real-time by Hayden at our factory. If you want to see more of his visit hit the link in our profile to an awesome feature which tells the story. #madeinaustralia #realreinforcement #notjustforlooks

A post shared by Colan Australia (@colanaustralia) on Jan 14, 2019 at 10:40pm PST

MrJ, thanks for the comments.

Do you know if anyone has ever attempted to quantify spring constants in the various foams? I imagine lower density means lower K (constant). I’m curious just the foam. Not including the layup or resins.

You see lots of people saying the board feels dead, or chattery. I read that to refer to the damping. Too much damping won’t have a high enough natural frequency while a chattery board may be under damped for what the rider may be accustomed to.

thanks for spelling that out. Its not quite how FW presents it. What is FST?

Hope I’m not hijacking too much nor going too deep off the engineering deep end. I found this interesting in regard to my question to mr j.



FWIW, 16kg/m^3 is basically 1lb/ft^3 density.

from: http://www.pg.gda.pl/mech/kim/AMS/022006/AMS02200605.pdf

This is specific to PU foam and a lot of the conclusion is specific to barge design but gets into similar ideas of what may cause a PU board to feel “dead” after a while.

This is very true, but couldn't the same be said for 2 identical PU/PE boards?

HS uses 2.1 pcf as their standard for custom FF builds. Not sure if the same is used for their offshore FF boards, but they have blanks that are 3% more dense and 3% less dense available as well.

The standard glass schedule on the HS FF builds is a quadaxial layup on top totaling 10.5oz of E-cloth and 4oz E-cloth on the bottom.

I really like the way they feel. Haven't had a single issue with durability and the board is nice and light.

Yes, it is. And I would believe anyone who has ever ridden a team light board has felt it themselves. Assuming the foam is our spring and the glass schedule is our damping, a lighter layup will have more “pop” while that 6oz heavy glassed board will be stiff but may be better equipped in choppy waves as far as chatter under foot.

It’s all about tuning the board for what you want to feel (and how much you are willing to spend).

so what damps more the foam or da resin?

fk foam im gonna get hollow boars from now on!

hollow boar: sum fugger ask me what density my foam is i’ll say same as the air yo’z!

You could alter the ride of the board with custom air fills from different locations.

helium ftw! call it the helium build lol

Hi sd 101, sorry for the tardy response, I been busy with work and surfing. That's an interesting suggestion of yours to measure damping.

I don't know about just foam, although I think the most meaningful measurements from a surfboard point of view would be with layup too. I am fairly sure no one has done a thorough investigation.

There are 3 things that can be measured that I can think of that affect a surfboards response.

1. Weight - heavy means less responsive.
2. Damping - low damping I think would mean responsive (and chattery).
3 Stiffness - divinycell, corecell and wood sandwich builds are stiff and very responsive, but stiff does not necessarily mean responsive otherwise short 3" thick trad fishes would be bouncing around the place and be super responsive.

Weight is easy. Measurements 2 and 3 above could be done by clamping the tail and cantilevering the board horizontally. Add a weight to the nose and measure distance it drops downwards - that would get us some stiffness measurement. Then with the weight still attached to the nose lift the nose some predetermined amount and release it and measure damping with something or other. I think clamping the tail rather than the nose would make sense, because that end of the board is loaded with boxes and carbon to stop rail crushing so would not be very flexible anyway.

I don't understand the equations for damping, maths is not my strong point https://en.wikipedia.org/wiki/Damping_ratio

Someone called Benjamin Thompson (materials expert and surfing nut) would be able to figure it out. He devised a way for measuring stiffness - that is to find natural frequency - higher the frequency the stiffer the board, so it seems that frequency is not related or directly proportional to damping. Otherwise shock absorbers would have no damping effect on a cars springs if stiffness of springs completely determined damping.

cheers jkb, That's good to know. I have a feeling that you have told me all this before, but my memory failed me - must be old age

Deck sounds strong, bottom sounds average and rails would be strong from the carbon. A lot of how a board lasts depends on how the user treats them. Some surfers are a bit careless and knock them around a bit or go surfing in rocky places where it is difficult to get in and out of the water without mishaps - they would benefit from a strong shell all round. Others are quite careful, but really heavy with the foot pressure and need a strong deck rather than hull.