Does anyone know the difference between the stage 2,3,4 and 5 Greenough fins? I’ve seen pictures of the templates but I’m curious as to function of the different shapes. Information on any of these fins would be greatly appreciated. Thanks!
Does anyone know the difference between the stage 2,3,4 and 5 Greenough > fins? I’ve seen pictures of the templates but I’m curious as to function > of the different shapes. Information on any of these fins would be greatly > appreciated. Thanks! Where to begin… years ago, George Greenough told how to make the fiberglass blanks for his stiff, tuned, high-aspect ratio fins: start with completely resin-saturated, unidirectional glass strands (you can easily take roving apart to get it),carefully placed on the floor in an oversized, plywood female mold, a matching (male) plywood lid was laid over that and then the weight of a car or truck was jacked up over the top of the mold until the excess resin was squeezed out and the cure cycle was complete… resulting in an extremely high fiberglass to resin ratio. Searching further, back issues of "The Surfer
s Journal" (in such fine articles as "George Greenough, Ageless Artist", by Paul Gross) have excellent background information on Georges efforts with his fins and other projects. In part, he achieved the functionally balanced, neutral handling he sought by way of developing a series of fins which were very efficient and controllable at high speeds. Under the right conditions, and when coupled with hard, driving turns and critically placed trim positions, the sensitive use of his flex spoon kneeboards (older fiberglass and latter, carbon grahite “edge boards”) in concert with his long, relatively thick, stiff, tuned and raked high-aspect ratio fins resulted in trememdous amounts of useable, stored energy to focus and drive his kneeboards. His concepts and the skills that drove them, were so potent (and ahead of their time), that the resultant widespread use of his kneeboard design elements, often crudely applied to conventional surfboards, forever changed the face of surfing. The results were (as many of us are old enough to remember) nothing less than historic. Three decades later, the performance levels of George`s designs, his ideas, craftsmanship and surfing ability still stand as truly original, inspirational and valid goals to study and emulate.