Question on an idea i had

I was reading the Rocket Science post the other day and thought of an idea for board. Specifically related to the nose. The parts of Rocket Science referring to spray root. I was thinking what would happen if you were to put a concave leading to shallow channels following off to the rails. Would that lead to less friction and more speed or maybe better planing?? Just thought any feedback welcomed.

…In my pointy-er nosed boards, I put a little roll or vee in the first 3 or 4 inches of the tip.This is to deflect mass.It is slight, and one would have to look for it or have a well seasoned eye to detect it.Herb

I have a 7’10" egg that has a wide round nose with 1" chine rails…The first foot or so has a hard edge concave right off the chine…I find that the chine prevents grabbing while the concave directs the nose during full rail turnsParticularily on hard backside bottom turns…I like it but, then again my boards aren’t for everyone…one of the benefits of making and fine tuning ones own equipment…experiment… http://www.hollowsurfboards.com

I used both a slight V and then trasition into 1.2 inch chines. Be careful not to put to much vee roll and don’t continue it to far down from the nose–you do need some flat bottom for planing. However, up by the nose I get good rail to rail transition which is then helped out towards the middle of the board and towards the tail----fat trasitions and white wash climber!!!

Howzit Herb, that vee or roll helps with easy entry when catching waves also. Aloha, Kokua

Hopefully, you recognized that the planing that Kevin is discussing is at almost 90 degrees to the commonly assumed planing of a surfboard. When you paddle a board or just catch a wave, your board is planing “nose to tail” but the spray is displaced off the rails by the fact that the board is longer than it is wide. This is NOT the planing that Kevin is talking about. Kevin’s analysis describes how a surfboard planes when it is turning or trimming. The board’s spray now flows from inside rail to outside rail. Concave lift occurs because the inside to outside rail spray is deflected downward by the concave. That provides “lift”. My gut feel is that a single deeper concave running the entire length of the board will lift more than several shallow channels. The deeper the concave, the more lift. The design problems with a single deep concave are that the lift may be too efficient leading to control problems (spinning while turning, tracking while trimming). The problems are dealt with by shallowing the concave or moving it around. The common misconception that channels grab the water and redirect it toward the tail is proved by looking at the wake of a tow board trimming along a Jaws wall. You can see clearly that the wake left behind shoots out at right angles to the direction the board is moving. The concave is lifting the board but not directing the wake. Look at any photograph of a board trimming or turning; the wake goes straight from inside rail to outside rail. The only way that the spray can be deflected aft is by a fin (the rail fins on a thruster or vent fins on a bonzer. If you put a fin along the length of the rail to really gain the affects of redirection, you would lose speed because of the drag the fin creates. That’s my answer, anyway…

Thanks Lee and everyone else that pretty much put my question to rest.Like i said it was just a thought i had and now i understand.