The first surfboards were usually made from Hawaii’s local Koa tree and reached lengths of 16 feet long. Although extremely buoyant these surfboards were also extremely heavy.
A 14-foot board would weigh as much as 150 pounds. Modern surfboards are made of polyurethane or polystyrene and are covered in fiberglass sheets and coated with epoxy resin.
The result of these materials being used to create the surfboards ensures a much lighter and even more buoyant and maneuverable board.
Modern surfboards are also much shorter. They range from 5 to 7 feet and have a more pointed nose than the original rounded nose of the earlier long boards.
They are not nearly as wide either and this feature is what makes them more maneuverable. The short board is what you will see professional riders on during competitions.
Another advancement from the long board to the short board is the introduction of fins. Fins help the board to -stick-to the wave.
Fins are placed differently on boards and thus causing different advantages to their placement.
The most common placement is called the Thruster. It consists of three fins. One is placed nearest the tail and the other two slightly forward towards the nose.
The idea behind the placement is to have the maneuverability of a twin fin and the stability of a single fin board.
Hans-Peter Oswald
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