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6 Dec

The Fins the Thing: a celebration of surfboard design from the single fin to the thruster

by Sam Bleakley

Reef surfer at The Wave in Bristol

1935: The Year Of The Fin

1935 could be called ‘The Year of The Fin’. It was when one of the most enduring contributions to surfboard design allowed a quantum shift in riding styles. American, Tom Blake, tore a fixed keel off a washed-up speedboat and reattached it onto the bottom of a surfboard. It was transformative: the fin allowed Blake to ride on a tighter angle across the wave. Although not readily adopted by most surfers until a decade later, the skeg of course became an integral part of surfboard design.  

Blake used his original fin at Waikiki in Hawaii. “When I first went to the Islands, they used wide-tailed boards and they used to spinout on a steep, critical slide,” said Blake. “I figured it would be easy to correct that problem, just add something - a keel. Finally, I got around to it. You didn't hurry things up over there. You were having too much fun surfing every day. Finally, I put a fin on the board and it worked fine. It was a shallow fin, about 4 inches deep and a foot long. It took ten years for that thing to catch on and then the boards kept getting lighter and smaller and (then) the fin became more effective for steering.”  


In late 1940s California a combination of post WWII fiberglass materials and an eccentric engineer and mathematician called Bob Simmons generated huge advancements in surfboard design. Boards were heavy and cumbersome, and Simmons wanted to make them lighter, easily handled and more readily transported. This would promote inclusion. Post-war California was seen as a spearhead of liberation in terms of social values. Simmons was interested in the scientific principles of planing hulls, nose-lift, foil and finely sculpted rails. By 1949 his boards were made from balsa and resin-saturated fiberglass, praised for its combination of flexibility and durability. Simmons also made double-finned boards, which Tom Blake had experimented with on a hollow timber board in 1943. Tragically in 1954, 35-year-old Simmons was struck in the head by his own board during a large swell and drowned. But he had inspired a group of Malibu-based boardmakers to incorporate his design features into the easier-to-turn Malibu chip single fins. These in turn influenced the classic ‘hotdogging’ longboard styles of the late 1950s and early 1960s embodied by the likes of Marge Calhoun. 

1960: shorter boards and RADICAL RIDING STYLE EMERGED

1960s single fin designs were generally quite crude with ‘D-shapes’ the norm. This changed when kneeboarder George Greenough started making beautifully foiled dolphin-like fins. In 1966 Australian Nat Young won the World Championships using one of these riding with an aggressive style, carving arcs and ‘S’ turns. Greenough, riding short and stubby kneeboards, was showcasing on his knees what could be done standing up. He thought that surfing could move from straight lines to short arcs, but the big boards and crude fin shapes would not allow vertical turns and the use of a low centre of gravity. Greenough enthused a handful of trailblazing Australians to build shorter boards. With vee-shapes on the bottom the new boards had deep, flexy single fins. When the Australians travelled to Hawaii with these boards in 1967, surf communities around the world started shaping shorter and shorter boards, and radical riding styles emerged. 


Most champion surfers like Margo Oberg and Rell Sunn used single fins throughout the 1970s, but there was also a core following of the twin fin. In 1967 San Diego brothers Nick and Bear Mirandon had developed a split-tailed, two-finned board. This lead to the Steve Lis ‘fish’, loved by kneeboarders. A thick, squat, square-backed version of the twin-fin, developed by Californian Mike Eaton and refined by Australian Geoff McCoy, also came and went in the early '70s. Then in 1976 Hawaiian Reno Abellira travelled to Australia with a wide, blunt-nosed 5'3" board with two fins. A young Mark ‘MR’ Richards was immediately inspired to make a longer and more streamlined version of the twin-fin to improve his small wave surfing, explaining that the boards were “fast and maneuverable” and that he “felt like he could do anything on them.” In 1977 MR had a two-month-long shaping seminar with Hawaiian guru Dick Brewer, and soon developed his own 6’2’’ twin fin model, featuring a pair of six-inch-high fins set along the rails, and importantly angled at the nose (not parallel to the rails), about 11 inches from the tail. He immediately described this as “the ultimate small-wave board.” MR was electrifying in the line up, confident throughout every slice, glide and hook, but cool, humble and easygoing on land. He won four consecutive World Titles between 1979 and 1982 (but still used the single fin in big wave Hawaii). Dane Kealoha and Martin Potter were outstanding on their twins, but MR's main rival, finishing runner-up to the world tour in 1979, 1981 and 1982 was Australian single fin rider Cheyne Horan, arguably the best surfer to never win a world title.  

While MR was dominating on the twin fin, Australian Simon Anderson, a lanky power surfer and shaper who mixed driving turns with languid grace, was frustrated with the spin-outs and was seeking more grip on the wave-face for forward drive, not sideways slide. “Back in 1980 there were two schools of thought,” said Anderson, “the single fin camp and the twin fin camp. The contest tour at the time was going to a lot of new countries like Japan, England and Brazil. And we were finding that the waves were generally small, and to match Mark Richards - who was winning on his twin fins - we really had to do something about our equipment. For me being in the single fin camp firmly, and a big guy, I found great difficulty on the twin fin because it’s essentially a very fast, very loose board that is difficult to control, and you need to surf it a certain way. So I was reluctant to give up the single fin. Then in October 1980 I was back in Sydney surfing Narrabeen where I live, and a friend of mine who works in the surfing industry called Frank Williams came out of the surf. He had a twin fin with him and there was this little stubby fin in the back of his twin fin board, right on the swallow tail about an inch high. So I asked what that was for, and he said it helps make the twin feel a bit more stable. I immediately thought I'm going to make that real stable and I'm going to fit the whole fin back there.” 


Simon Anderson used a square-tailed board with three like-sized fins, all smaller than those used on a twin-fin. He called it the Thruster - although he never patented the design - the third fin adding thrust to the board's turning capabilities. Other shapers had dabbled in three fins before. Back in 1970 Dick Brewer and Reno Abellira designed one. Then in 1972 Malcolm and Duncan Campbell had introduced the bonzer with a pair of toed-in, keel-like side fins, located in front of a standard centre fin, and two parallel concaves through the bottom tail end of the board. Ian Cairns, Jeff Hakman, Terry Richardson and Russ Short loved them, but the design slipped through the cracks and didn’t catch on until the retro revival of the 2000s.  

The thruster made an immediate impact. “I wanted to make my equipment really good,” said Simon Anderson, “so when I went out there I'd surf really well, and if I surfed really good, when I came in I'd be really happy. That was kind of the cycle, and it was a good cycle and it lasted for years." After a stunning competition run in Australia in 1981, Anderson concluded the year with a heroic victory at the Pipeline Masters in Hawaii. “Surfers are never satisfied with the status quo and they want improvement all the time. We have got imaginations and we want to surf in a different way from before. So the more we develop boards and the more sophisticated they become, the more able we are to go back over pre-existing designs and add those elements and bring them alive.” 

An updated five-fin version of the bonzer was developed by the Campbell brothers in 1982 and surfers could now choose from a limitless array of fin set ups, including four fin quads, twins and classic singles. But the thruster became the standard – possibly the most influential design feature in the evolution of the surfboard, reshaping surfing styles of the future from Lisa Anderson to Carissa Moore, to Sky Brown.