Design Note: Rake

The rake is the amount of sweep a fin gets when assembled to the board. The rake is the angle measured between the vertical to the board and the Leading Edge (LE) or Trailing Edge (TE) of the fin. Different fin manufacturers specify their fins sometimes by the TE-rake and sometimes by the LE-rake.

We normally use the LE-rake as reference but you can also find the TE-rake engraved into the fin’s base.

The rake influences different characteristics and parameter of the fin. An important parameter is the amount of geometric twist the rake is responsible for. As more rake, as more geometric twist the fin will have. The geometric twist is one parameter defining the load distribution along the fin length.


Rake sketch