materials in surfboards

Materials Used In Surfboards

Foam Blank – Almost 100% of surfboards in the lineup today are made with polyurethane or polystyrene (Styrofoam) cores. The foam blank arrives to the shaper in the crude outline of a surfboard shape, including varying degrees of rocker. Your shaper then starts “mowing foam” as he shaves off the excess foam until he arrives at the shape of your next surfboard. Two forms of Polystyrene are the most common: Expanded Polystyrene (EPS) and Extruded Polystyrene (XPS). 

Fiberglass cloth - A shaped foam blank is too weak and porous to use in the water on its own. To strengthen the surfboard a layer or two of fiberglass cloth is applied to the entire length and width of the surfboard, both deck and bottom. The most common fiberglass used is 4oz and 6oz cloth. Shapers have started using alternative materials to strengthen a surfboard, such as Kevlar and carbon fiber or natural materials like hemp based cloth.

Resin – The glasser must use a resin to bond the cloth to the shaped foam surfboard design. The resin is poured onto the cloth and the board until the cloth is completely saturated. The polyester resin has been used since the 1950s and is still the most commonly used today. Epoxy resin has gained popularity over the last several years due to its increased strength and ability to create lighter boards.  Both epoxy and polyester resin may be used with polyurethane foam, but only epoxy may be used with polystyrene foam. Polyester will destroy the polystyrene structure at the point of contact.

Some epoxy surfboards have a plastic look. These boards do not allow you to see the foam blank, the fiberglass cloth, or the stringer beneath the exterior.  They are built with what is called a sandwich construction in which the shell is made and then filled with foam.  They tend to be stronger and better at resisting pressure dings that form by standing on the the deck, though the material also has an effect on the flex pattern.

Stringer - This wood structure typically runs down the center of a foam blank. It provides strength and flex memory for the surfboard. Some shapers will move the wood stringer from the board’s center to its rails, creating better flex memory. Common wood types used in stringers are bamboo, balsa, Basswood, Western Red Cedar, and Englemann Spruce.