Thanks again. Wanted to see if I could 'retrofit' a thick fin rail for more bite (turning)
I had done resin beads for the edge using strands of finrope and adding milled fiber to the resin. That gives you a hard edge you can really hone. I use a rounded rail shape with the edge tapering from 1/4" in front of the fins to maybe 1/8" at the tailblock. I think the combo gives me a good compromise between hold and release.
A softer edge, all else equal, will want to slide sideways and will require larger fins. A hard rail in the tail forces water off and away from it, and its through this that you gain control and speed. If you are not pushing against water, somewhere, you are sliding sideways.
I experimented with this myself on a modern shortboard design with very soft, round rails throughout the whole board. It was a quad/thruster option, and even when using 5 large fins, it still would not hold and drive and wanted to slide sideways.
Keep the rails hard behind the front fins, fading to soft about 3-6 inches in front of the front fins.
I remember someone on Sways used to tape off and melt wax to create edges for experiments, surf them and modify until he was happy enough to copy the result in glass.
Thanks to all who responded above. My account became suspended again for some reason so I could not post any replies.
waxed tail - what a great idea! Can play around then use resin when the perfect edge was found, neat!
Light weight automotive body filler. I think it was Greg Loehr who did that.
Sharkcountry you have a good memory. It was GL. He did some crazy cool experiments looking for the optimum tail shape.
All the bst
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