When looking at surfboard design and performance as a whole, fins are one of the trickiest variables. Clearly, there’s a lot you can gather from simply looking at board length, width, or general shape. (And color. Didn't you know red boards surf faster?)
But fin setups are far more complex. A tweaked set up can create a board that rides completely different. Since there's no way to learn about fin configurations (or lackthereof) that compares with actually riding them, these are some of the basics.
Setup: No fins (Duh)
Boards: Alaia, Paipo
History: Pre-historic. These go back to the original surfboards made in Polynesia, before contact with Europeans. Finless surfing basically didn't exist for 70 years, only enjoying attention again in the last decade as wooden replicas of ancient boards and to some extent, soft top ocean toys. (Derek Hynd and Ryan Burch will blow your mind without fins.)
Characteristics: For all the control that fins give, they create drag. Finless surfboards are notoriously fast. Though purists ride thin, wooden alaia, there are also foam/fiberglass alaia. They're very difficult to ride in all but the most idyllic glassy, peeling surf.
Setup: One fin
Boards: Whatever you can think of
History: As far as surfing history can tell us, Tom Blake, who had earlier made the first hollow surfboards, first put a fin on a board in the 1935, a landmark advancement of modern surfing. Virtually every surfboard ever ridden for the next 40 years was a singlefin.
Characteristics:: In one word, they are classic, and the best option for the bedrock ’60s style of longboarding and ’70s style soul. Singefin surfboards are not the fastest, nor the best for direction change, but they can be used on any board from tiny slop to mid-lengths to big wave guns.
Setup: Two fins of equal size, usually a keel shape
Boards: Fish, groveler boards
History: Pioneering shaper, Bob Simmons gets credit for the first twin fin boards in the ’40s. They became functional through the 1970s to make boards faster and looser. Twin fins never went away, but didn’t see a resurgence until the ’90s modern fish movement, thanks to some inspiration from Tom Curren. They remain synonymous with the fish design and still very much functional.
Characteristics: Without that center fin, boards just go faster. For the most part, they don’t have the hold you’d want in steeper waves. Good for clean, non-critical surf and generating more speed in small surf.
Setup: Three fins, usually of equal size
Boards: The whole spectrum
History: When Australian Simon Anderson first came onto the scene with the thruster surfboard it caught on very quickly. For 30 years, it was almost all anyone rode from shortboards to lightweight longboards (also known as a 2+1 setup, with two smaller side fins and a larger trailer).
Characteristics: Still a major part of surfboard design, if you were to ask for a “standard” surfboard, especially performance, it would be the thruster. They hold in real waves and well proven for top level surfing. The trailer fin does slow a board down, which makes them less than ideal for average surfers in less-than-average surf, when you have to generate your own speed.
Setup: Four fin, two larger up front, with two smaller just behind and inside
Boards: Groveler boards, fish, performance shortboards and big-wave boards
History: Mostly experimental until the mid 2000s when they were used on performance boards for average surfers and became a standard option on all manner of craft.
Characteristics: A quad offers the pump speed of a twinny with most of the control of a thruster. Originally for smaller waves, spreading the fin placement toward the tail has made them a prime choice for speed in heavy water. They're also widely used by the pros now.
Setup: Five fins – a pair of keels forward, very close to the rails, and a trailer set back; also as three fins.
Boards: Shortboards and mid-lengths
History: The Bonzer was developed by the Campbell brothers of California in the ’70s, but got very little attention until the mid 2000s.
Characteristics: Somehow retro and futuristic at once, these boards are known for deep carves, not necessarily vertical or aerial surfing, but a board that can help any surfer do cleaner turns.
Setup: Four-fin setup with smaller fins slightly forward of and outside of the larger fins.
History: The twinzer was invented by Californian Will Jobson in 1988, became mostly obscure and regained a bit of notoriety in the 2000s.
Characteristics: Designed to have all the speed of a twin fin with a bit more maneuverability and hold for aggressive surfing.
In the end, ideally, a surfer would have a quiver that included all of these fin setups to be used for the proper conditions. But lately,convertible surfboards, with five boxes that allow a board to be a thruster, twin or a quad (and sometimes even a single fin) can be a versatile way to go if you only want one board for multiple options.
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