A Polyurethane, Varial Foam & Structured EPS 5'10" SUPERbrand Unit Tested
Surfersvillage Global Surf News, 5 November, 2015 - Polyurethane foam and fiberglass is cheap, abundant and has become the standard for surfboard construction. It’s been that way for almost 60 years now. Every other aspect of surfing gear has made technological leaps and bounds: fins, leashes, boardshorts and wetsuits. But surfboard materials remain the same.
PU is toxic and, relative to other materials, not so strong. There are options in the marketplace for a better build, constructions that are both lighter and stronger: EPS and epoxy; Firewire’s FST and LFT constructions and a few other new options like Varial Foam and Hydroflex. All of these offer superior strength-to-weight ratios. But PU is very, very familiar. For that reason all new surfboard-construction materials are compared to its performance.
We’ve all had that one magic polyurethane-constructed board, a board with flex properties that work perfectly for us. But PU flex properties vary from board to board due to a variety of factors: glassing, sanding, foam density and of course - wood stringer density.
PU has a shelf life. A board will surf differently after 6 months than it did right off the shop racks.
Jason Koons of SUPERbrand explains: “All of the structural support is in the 0 and 90 degree directions (parallel and perpendicular to the stringer)” says Koons. “The results are somewhat predictable, but with fluctuations in foam density and stringer grain the results for two boards shaped exactly the same can vary to a frustrating degree at the highest level of surfing.”
So how do the different constructions perform differently from each other? What if we tested PU, Structural EPS and Varial Foam/Hydroflex against each other? Well, we did…
For this review we tested the exact same board, a SuperBrand 5’10” Unit with the following dims: 20 1/2 x 2 5/8 at 33.5 Cubic Liters. We rode all three boards with the same fin setup: Futures V2 JC1 Black Stix.
The board tester is 6’1” and 190 lbs with an intermediate (to-sometimes-advanced) skill level but is by no means an expert surfer.
Full disclosure: This is not a truly scientific study. To do that we’d need a wave pool and surfing robots. But we did ride all three boards in a variety of beach break and pointbreak conditions. What follows is a breakdown of how each board performed as scrutinized and documented to the best of our abilities. Perceiving a surfboard as 'good' is, after all, subjective. OK, disclosure given; let's get on with it...
Board #1.) Polyurethane: The very same materials and construction surfboard makers have been using for around 60 years—polyurethane foam with a wood stringer running down the center.
Board #2.) Varial Foam in Hydroflex construction: Varial Foam is a new foam that’s lighter and stronger than PU. The company offers blanks with uniform and consistent flex properties throughout the blank. The blanks are lighter than PU and don’t have stringers.
Board #3.) EPS: Jason Koons claims the stringer-less eps core blanks are super predictable in flex and yield nearly the exact same results every time between two blanks. “Because the core has a consistent density from board to board and the multilayered glassing schedule is multidirectional we get a light predictable controlled product,” he added.
Board #1.) Polyurethane: The magic PU board is glassed with one layer of fiberglass S-cloth on the bottom and two layers on the top and set with polyester resin.
Board #2.) Hydroflex: The Varial board was glassed with epoxy Hydroflex tech. Hydroflex uses a method where resin is injected into the foam blank for strength - reports are that the bonding between the foam and lamination is 600% stronger than with traditional glass jobs. (We can’t prove that but it sounds great!) The tail patch on the Varial/Hydroflex board is an aerospace grade fabric.
Board #3.) SUPERflex: Glassed with a layer of glass that has additional strands following the nose-to-tail direction called Warp glass. Think of it as going with the grain in wood instead of against it. Then they add Vectornet (the net-looking stuff on the bottom) which adds strength and controls flex further.
What We Discovered
Polyurethane: We liked the PU board best for performance, liveliness and responsiveness. The board’s flex properties were amazing and familiar. There’s just something about the ‘zing’ you get from the first pump off the back-end of a PU board. Paying close attention we could feel the board twist and spring out of turns - think about it, we apply different levels of pressure to the front foot and back foot when pumping down the line.
That said, there are a variety of factors contributing to this PU board performing this way: blank density, stringer density, how the rails were sanded and so forth. Had I picked up the exact same board model (polyurethane, same dimensions, cubic liters, etc) it would ride differently and may or may not qualify for ‘Magic Board’ status as this one did.
One thing is for certain though, we did not like how fragile the PU construction is. In just a few months we’ve busted out a fin, creased the forward part of the board and smashed the tip of the nose.
Varial Foam: The Varial board had that quickness and sensitivity to it that a lighter-glassed PU board has. Best though was that the board didn’t chatter or bounce in chop like some EPS boards will do. It had the same positive drive familiarity as a PU construction. Also, the Varial has a quick, almost ‘slippery’ feel to it and its very responsive.
Varial claims that the blank will retain this zippiness for the lifespan of the board, and the board will also never yellow as it ages. The foam is resistant to UV rays.
The board is strong. We dropped it on the sidewalk (by accident of course) and suffered no chipping or shatters. We placed it on a tile floor and stood on it. It flexed without any ill effects. The Varial deck did suffer pressure denting - about the same as you’d get on a PU board.
Varial is much lighter. With pad and fins it weighs 6 pounds 7 ounces while the PU counterpart weighs in at 7 pounds 10 ounces. Varial has a nice float to it without feeling too ‘corky.’
Background - Varial was developed in the aerospace industry and has a tighter cell structure than standard polyurethane foam. According to the makers, the blanks are 25% lighter and are substantially stronger.
Varial Foam doesn’t use a stringer. Instead the foam is engineered to hold a similar flex pattern to that of a PU blank with a stringer.
So is it a deadringer performance-wise to a PU board? It’s very, very close. The only difference is the absence of the familiar wood stringer’s flex properties. Overall we really liked it. In short, it’s like getting a team-glassed PU board that will last much longer and retain the same performance characteristics. Of course, it will cost you more than a standard PU board.
Structural EPS: On a basic level it surfed lively and well. Conversely, it did feel a tad stiffer flex-wise and didn’t quite knife through the water as well as it’s PU counterpart. It was more prone to skip out when turning hard off the tail, more so than the PU and Varial foam versions.
For fifty percent of the sessions the SUPERflex board went fine. It worked better than the PU and Varial board in smaller, gutless surf. The other sessions it didn’t quite have that magic ‘zing’. This was more the case in bumpy surf. It felt more floaty than the other two builds.
The familiar materials of a standard PU blank © Boardcave
Polyurethane performs, but you never know what you’ll get off the rack with two identical models with identical dimensions due to inconsistencies in PU blanks and the laminating process. If you get a magic PU board, “keep it on ice” as one industry insider has told us. For good waves we’d choose PU over the other two.
The Varial surfs like a light, team-glassed PU board (even a bit more ‘springy’ feeling) but with excellent durability characteristics. The Varial is strong without many of the drawbacks of lighter, non-PU constructions: stiffness, chattering in chop or being extra floaty. The downside is it costs more (30% says Varial). Some surfers might not want a board that feels ’team light’.
The SUPERflex EPS is durable, light and better-suited to smaller surf.
Performance-wise: the SUPERflex EPS board is a good board; the PU counterpart is a great board, and the Varial Foam with Hydroflex glassing bridges the two, coming closer to the PU in performance than the SUPERflex