The surfboard design process can be described as building a bridge between shape and context, based on function. According to this approach, the designer is concerned with two sides of a relationship. On one side, there is the shape of the surfboard itself. On the other side is the surfboard's context, which is every external condition that influences its function.
The most obvious factors that play a role in a surfboard's context are physical in nature; from the surfer's weight to the size and shape of the wave. These are taken into consideration when deciding on a surfboard's length, width and thickness/volume. However, the ultimate aim of surfboard design is to relate shape to purpose, since the ideal is a surfboard that becomes absorbed into the surfer's intentions. So, the surfer's intentions are also part of the surfboard's context, making it part of the design process, too.
In considering the surfer's intentions, the designer analyzes how the surfer's movements affect the response of the surfboard. Basically, the surfer turns the surfboard by leaning his body and extending his legs and feet to varying degrees. However, it is not the mechanics of the human body that concerns the designer, but the net effect. So, the designer reduces the surfer's influence to a set of rotational axes. At this level of abstraction, the surfer's intentions can be represented diagrammatically, enabling the designer to more easily visualize the different phases of a maneuver, as well as the transitions between them.
Whatever the axis of rotation, maneuvers can be divided into two phases, a penetration phase and a release phase. The penetration phase is characterized by the inward rotation of the surfboard, while the release phase involves its outward rotation. By visualizing each phase in terms of its rotational axis, or sequence of axes, the designer can identify which portions of the surfboard come into play for a given maneuver.
Having established a link between the surfer's actions and the under surface of the surfboard, the designer is ready to include the notion of resistance. Since the greatest amount of resistance is achieved by rotating the surfboard sideways, the penetration phase of a maneuver tends to be characterized by rotation of the board in or near to this plane. By contrast, the release phase is characterized by a transition from this rotational plane toward either the center plane, by directing the water out through the tail, or into the horizontal plane, by sliding the tail out. The horizontal plane obviously provides the least resistance, since it is limited to the surface area of the fins. However, the loss of resistance felt in the central plane results from the surfboard's rocker allowing the water to escape through the tail.
The blending of these curves, which fan out from the center of the board, influences the transition from rail-penetration to release through the tail. Although curvature from nose to tail and from side to side, by themselves, determine the extent to which penetration and release contribute to a surfboard's performance, it is the blending of curves between these two extremes that ensures that the board enters and exits turns smoothly and with minimal loss of speed.
Although surfboards can be represented in 3D, with movements reduced to rotational axes, surfing maneuvers are as much the transition between rotational axes as the axes themselves. The shaper's ability to equate the shape of a surfboard with how it responds is drawn from the feeling of the board under his feet. A good design becomes an extension of the self, allowing the surfer to become intimately acquainted with the wave.
Copyright © 2005 by Dan Webber.