FCS: Fin Characteristics


  • The length between the leading and trailing edge where the fin meets the board.
  • Base is primarily linked to drive. Fins with a longer base will offer substantially more drive and acceleration.


  • The distance the fin penetrates into the water.
  • Depth directly relates to hold. The greater the depth the more hold, the shorter the depth the more a board will slide and release.


  • The angle measuring how far the outline of the fin is curved backwards; also referred to as rake.
  • Sweep has a direct influence on pivot. Fins with more sweep producea longer turning arc, less sweep offers a tighter turning arc.


  • Refers to the distortion of the fin from its original shape caused by lateral pressure during a manoeuvre. Flex influences the response characteristics of a fin.
  • Fins with little flex (stiff) produce instant response, speed and drive. Fins with more flex (flexy) are more forgiving and offer a whipping sensation.


  • Refers to the angle of the side fins measured from a vertical line perpendicular to the flat bottom surface of the board.
  • Cant has a direct effect on acceleration and manoeuvrability. Less cant produces faster acceleration and a stiffer feel. More cant will increase manoeuvrability and gives the board a loose feel.