Epoxy vs Polyester

For almost a century, polyester has dominated the marine industry. In the beginning, surfboard was made from a simple dark boat resin with basic woven fiberglass cloths. Because of its clarity, consistency and ease of use in last decades, Silmar became the standard and is found in most surfshops. As it was still relatively brittle, later Polyester resins, like ISO10x, improved the impact strength, consistency, clarity and UV resistance. ISO10X is a non-inhibited Resin still found in good surf shops Europe wide.


Back then, Epoxy surfboards were stiff, often broke easily because of lack of flexibility in the laminate and always hid a multitude of manufacturing problems. With development and application in aero industry for the last 30 years or so, Epoxy resins are changing the nature of surfing in many ways. Not only Epoxy resins have superior strength in matrix, it also benefits from a total lack of solvent, which is a factor in the decay of strength of Polyester resin, when it remained uncured or trapped. The solvent used to expand under heat or stress, causing delamination. Later, wax was added as inhibitor to Polyester Resins (still is today), to increase productivity and turnover and to help reduce solvent emissions (affecting nervous system). But problems of solvents affecting laminates remained. The modern clear, fast and safe Epoxies contain qualities unheard of even 5 years ago. With elongation at break with up to 6% they are side by side with the best Polyester resins. Their compressive strength and impact resistance was vastly improved, some surfboards were even proven “unbreakable” in every day use.


Epoxy Surfboards will last longer, have less damage and almost no pressure dings improving their green level by over 300%. With combinations of recyclable super fused EPS cores, the boards have feel and performance beyond anything achievable with Polyester Resin, that melts EPS. there are also bio based, degradable Epoxy resins (Entropy) which we also use upon request. Mixing Epoxy Resins is also less toxic, safer and easier to use. Taking into account UV resistance and clarity and the choice becomes easy.


The only advantage that Polyester resins still have over Epoxy resins is that quality Epoxy resin usually costs more than twice as much as Polyester resins. But the costs of production in reality are probably only 35% higher. Consequently Epoxy surfboards tend to cost only about 30 – 40 % more than Polyester surfboards but their life span is far far longer over Polyester surfboards.

Surfboards made with Epoxy resin are still much viewed with suspicion in many legendary surf places. First question we get when we are introducing Epoxy surfboards is “what about the flex”.

Still, Epoxy surfboards are so far only a choice of “smart” surfers that are aware of consequences using friendlier materials on the nature and cost effectiveness on the longer run. This is slowly changing now a days and will become standard in the future.

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