Design Your Surfboard Starting at the Fins

Design Your Board Starting at the Fins

Fins and fin placement are the most underappreciated aspect of surfboard design.

Before you start mowing foam, in the design process, it is best to ask yourself "How do I want this board to surf, and in what waves do I want to ride this board?" Loose and skatey for small mushburgers? Super fast and drivey for surviving monster barrels (or more likely closeout sections)? Boosting airs?

Fin position, toe-in, and cant, as well as fin template, foil, rake, and material all combine to produce a specific hydrodynamic output. 

We've been kind of brainwashed as boardbuilders with the standard 1 1/8" - 1 1/4" in from the rail, 1/4" toe-in, blah blah blah. 'Safety positions' for standard copy-cat outlines. Do those positions even work best? Or do they just satisfy the need to put fins somewhere on the board?

Ever try placing your fins 1" from the rail, less toe-in and using a smaller surface area fin? Guess what, blazing speed and great hold in steep faces. Bigger fins placed 2" from the rail for a twinny setup? You’ll get a looser feel without sacrificing drive for smaller waves...

There are an infinite combination of fin setups to use, just know there are possibilities out there if you look out of the box and know a little about design.

It's all about your back foot:

You should know where your back foot naturally lands when popping up and plan your fin set up from there.

Lay a surfboard outline template on the ground and do 5 pop-ups on it. Measure your back foot distance from the tail each time and average the number. My personal average back foot distance from the tail is 12”... I design my fin placement with that 12” point as my “Neutral Zone”.

I use this knowledge as another factor in designing this board to surf the way I need it to in certain conditions. When the middle of the front fins of a tri or quad set up are around 12” from the tail I will have a balance between turning and drive (outline curve and tail rocker aside). Pushing those fins back an inch or two behind my back foot position will provide more drive in the board. Putting the fins a bit more up in front of my 12” will lead to less drive and a more pivoty, skatey feel.

Of course we move our back foot around while surfing to change the drive / turn dynamic of the board at certain moments but starting with your fins positioned optimally for your take-off will improve your surfing greatly...

 I could go on and on about fins but I'll stop for now. In closing here's a post-session text message from a buddy I was surfing with recently:

"Never would of thought that the wrong fin created so much havoc. What a difference just changing that 1 trailer made. Thanks for the heads up brotha!"