subject: The Fiberglass Surfboard - Materials and Construction [print this page] The Fiberglass Surfboard - Materials and Construction
Polyurethane foam is typically used for the traditional fiberglass surfboard. It uses a CNC machine for the shaping of it or it can be hand shaped. The core is of a foam polyurethane. Before a polyester resin is used for lamination, the weighted fiberglass is laid over the foam core. After this, the board is then sanded to perfection and then it is cured. These boards have been made and used since the 1960's and have proven to have wonderful flexibility and high performance.
There is of course another type of foam that some companies will use when making their surfboard. This type is an expanded polystyrene foam that is able to keep its shape by having an open cell that will take in the water that it is exposed to. Of course, there are some limitations with this material such as the fact that it is considered poor in terms of strength, it has a low resistance to compression and it is extremely hard to shape because of all of the round particles that are very small. The lamination for this type of material used in Epoxy resin.
For those who want a fiberglass surfboard that is better at repelling water and great with compression, the core foam of extruded polystyrene is what you want. The board has a lot better response when it is under a lot of compression because of the great flex patterns it has. This type of core foam is what is now being used to make a lot of the high end surf boards. For the lamination, an Epoxy resin is used.
There are various grades of fiberglass matt's used and the weight is determined in ounces. If you want a strong board, you will want a cloth weight that is on the high side. Of course, this makes for heavier boards but that is not because of the weight of the cloth itself. It is because there is a need for much more resin in order to properly bond the board and the fiberglass matt. Generally, this fiberglass surfboard will have many layers on the deck with only a single layer on the bottom. This is because the knees, elbows and the feet of the surfer will be on the deck so more protection is needed.
Some fiberglass surfboard builders have attempted to build boards using a Styrofoam core instead of polyurethane, and use an epoxy resin instead of polyester. This makes the board have a much lighter weight, better impact resistance, and stronger construction. The use of epoxy resin also makes less toxic fumes as well. The bad things about making these types of boards are that they take a long time to make, cost much more than traditional boards, and have a complex process for manufacture. Sometimes, graphite cloth is used instead of fiberglass. However, this costs even more and can only be made in the color black.
New techniques to making surfboards use a computer controlled shaping machine that can fully sand and shape a blank in just 25 minutes, instead of the many hours needed for hand shaping. Drawbacks to this are that the machine is expensive and has to be reprogrammed each time a new design is needed. Another way that has been tried, is using a premade surfboard as a pattern, and then making the shell and filing it with foam. It takes about 4.5 hours to finish the whole thing. It is very costly to make it in this way, and new designs can only be made when there is already a fiberglass surfboard there to use as a pattern.
Different construction methods are preferredby different people. Many still like the traditional and slightly heavier boards due to their ability to cut through choppy water and hold their edge in powerful turns. Others love the weightlessness of the new technology boards. Their extra buoyancy allows shapers to make thinner, lighter boards that suit aerial and tech surfers.
