Posts filled under #surfboard

About 3/4 of the way thro

About 3/4 of the way through this video, he finally lands the 360 turn and keeps on surfing. This is a shortened clip of what could only be considered an epic ride. After he landed the 360 and kept surfing, he got down on his knees and knee boarded, then he got on his belly with his arms outstretched and body surfed for a bit, and then he stood back up and kept surfing for a few more minutes.#360 #surfer #wakesurf #wakesurfing #first #trick #tricks #justdoit #lake #wake #goforit #no #rope #badass #summer17 #summer #surf #surfing #lakelife #boatlife #boating #watersports #water #sports #liquidforce #board #surfboard #epic

An extract on #surfboard

Most shapers today design surfboards using computer programs to generate data that can be supplied to a computer cutting facility which will mill the raw foam blank within 90% of the finished shape, leaving the shaper to fine-tune the blank to its final state before glassing. This method allows the shaper to have a very exacting and reproducible design which can be easily fine-tuned and adjusted. Wooden surfboards are making a comeback as an eco-friendly alternative, requiring ultra-light boatbuilding skills. Many professional shapers outsource the highly specialized task of lamination to specialized "glassers", who laminate fiberglass to the foam core of the surfboard using thermosetting resins like polyester or epoxy. Fins and assorted plugs are usually installed after this process and the final product is fine sanded and often glossed with buffing compound and special glossing resin. When shaping, the shaper often takes into account the specifications of the client surfer, and molds his medium to best accommodate the user's personal surfing style and wave of choice. Shapers play a design role in some companies that mass-produce surfboards. Surftech manufactures boards in molds designed by prominent shapers.

Historically, surfboards had no fins; some amount of control was achieved through convex hulls and the surfer dragging a foot in the water. A common problem with these early boards was "sliding ass", in which the tail would slip sideways, usually causing a wipeout. The first fixed fin was introduced by surfing pioneer Tom Blake in 1935. In Waikiki, Blake attached a 12-inch (30 cm) long, 4-inch (10 cm) deep metal keel from an abandoned speedboat to his surfboard, and was immediately impressed with the results. Around 1936, Woody Brown independently added a fixed fin to his second surfboard design in San Diego, which further popularized the feature. The stability and control fins allowed revolutionized the sport, though many surfers avoided them for several years; evidently they were thought dangerous. The feature grew more common in the mid-1940s and became the universal industry standard in the 1950s. Experimentation with fin design and configuration increased after 1966 with the popularization of shortboards. Parallel double fins, first introduced in the 1940s by Bob Simmons, became periodically popular. In 1980, Simon Anderson introduced the three-fin "Thruster" design, which has since become standard.

In surfing, there are two major types of (typically stationary) surfboard fins (hydrofoils), and a host of illustrative issues. Both a skeg and "rail fins" stabilize the motion of the surfboard. They also contribute to the desired effect of converting the (kinetic energy) push of the sloped wave face combined with the rider's mass on the sloped wave face (potential energy) into redirected energy - lift (lift (physics)) - the surfer deflects his surfboard and fins off the water of the wave face (and/or vice versa) to make forward progress across the wave face, or "down the line," that is, parallel to the wave crest and beach - riding parallel to the crest (perpendicular to the pull of gravity down the wave's slope) in this way is known as "trimming." Lift (aka "drive") from the board and its fin(s) is what enables all maneuvers in surfing. A "skeg" (an upright, streamlined, often raked keel) typically denotes one centrally-mounted stabilizer foil mounted perpendicularly to the riding surface, at the rear of the surfboard. Smaller surfboard fins mounted near the edge (or "rail") of the surfboard are known as "rail fins" and are seen in multi-fin arrangements (often in combination with a similarly-sized central fin further back on the board). Rail fins enable high-performance surfing, and are most often "single-foiled," with one flat side and one "foiled" side, as seen on an airfoil, for greater lift. A fin configuration with fins near the edge of the board stabilizes and contributes lift during turning maneuvers, which contributes to the board's ability to "hold" during turning maneuvers. Rail fins are often seen in addition to a central fin, but can be used without a central fin as well. Some of the most popular multi-fin configurations use two rail fins (a "twin-fin"), two rail fins plus a similar-sized central fin mounted further back (e.g. a "Thruster"), or four fins (a "quad"). Rail fins are more or less engaged by the rider's heel and toes as they lean in the desired direction of their turn. As the rider does so, an "inside" rail fin sinks deeper and its angle of attack is increased, as is its lift-induced drag. Rail fins also add lift (known as "drive") in trim and with greater holding ability, enable steeper wave faces to be ridden and higher speed "down the line." Rail fins are typically "toed-in," that is, the leading edge of the fins are oriented toward the centerline of the surfboard, which decreases the angle of attack in trim, which makes it easier to initiate turns. "Toeing in" rail fins also adds drag on the "outside" fin, as its angle of attack is negative during trim or in a turn. These combined factors of toed-in rail fins cause several issues: drag on a toed-in outside rail fin can slow the board down in trim, but it can also give a braking effect during turns that is useful. The inside rail fin (and the board itself) can be "pumped," attacked and re-attacked, by swerving up and down the face, causing acceleration down the line, or similarly pumped to achieve a desired trajectory through a multi-stage turn. At higher speeds, the drag off toed-in rail fins can cause surfboards to oscillate and become unstable - a phenomenon known as "speed wobbles". Most surfboards intended for larger waves are longer (to increase hull speed for paddling, wave-catching, and surfing), and as most shapers orient the rail fins toward the nose of the board, a longer board inherently results in reduced toe-in of rail fins, therefore less negative angle of attack, less oscillation, greater stability, and higher speeds. Rail fins also typically have some degree of "cant," that is, are tilted out toward the rail they are adjacent to. This is a significant additional factor in lift at various attitudes, drag, and performance, as are the variables of other foils - including flexibility, thickness, and planform. Rail fins evolved into being and surged into popularity as riders (Simon Anderson, most famously) sought a solution to two major performance issues of a central "single" fin - both related to engagement of the foil: For one, a centrally-mounted fin is tilted up out of the water as the board is leaned over, and thus it loses more and more of its lift as the lean angle increases - if the lean angle is acute enough, the fin's tip can be the only area left in the water; the tip may then rapidly stall and, having lost its lift, become disengaged from the water, leaving the board's bottom as the only control surface still operating. Before rail fins became (extremely) popular, this tendency of "single fins" led to riders "nursing" turns - this tendency was a significant limiting factor on performance. The enhanced hold offered by rail fins during turning led to more types of maneuvers being possible. The other major issue leading to rail fins' use is the fact that a rider can use the lift near the rail to increase speed and performance on smaller waves due to the above effects and abilities of these foils. Conventional statics fins suffer from the inability to have a camber and attack angle always adapted to variations trajectories. The angles given to rail fins are a compromise generating straight drag and oppositions in maneuvers. The center fin merit of being able to adjust its suction face and its angle with the direction of the turn to avoid the hydrodynamic stall. The fin camber and attack angle needed to accord to the different phases of trajectory. When turning left or right the fins need to adjust the camber and attack angles to avoid hydrodynamic stall, so the Adaptive Dynamic Attack & Camber system (ADAC) brought a solution to this hydrodynamic problem. This surf fin technology introduced adaptable structures with variable geometry inspired by aeronautics and biomimetic in the surf. In Windsurfing, a derivative of traditional surfing, skegs are also often used as a central stabilizing fin (hydrofoil) located at the rear of the board. A windsurfer's skeg also has the effect of producing lift, which allows the rider to direct the craft laterally against the lift the sail (itself an airfoil) produces. The skeg has undergone numerous phases of development and, as with other foils, its design is determined by the balance of the pressures it experiences in use, including lift, drag (physics), ventilation and stall (flight).