My question is about the placement of the features like concave and belly. Seems most of the start at the end of the nose. Ive been going through almost every magazine and video i can get my hands on and looked at all the noserides and almost every single one you can see that the last couple feet of the nose is clearly out of the water. A few…very few where the board rocker looks rather flat appears to show the nose or inside rail of the nose actually making contact with the water. Has anyone tried to reposition a concave i.e. where it starts, transtion to max depth and where it ends? I mean a concave looks real pretty up there at the end of the nose but how functional is it in that position?
I was told by one big name shaper that part of what makes nose concave help with nose riding is the trailing edge of the concave directing water downwards, and thus an upward force being applied to the nose. This made sense to me, much more than most of the other explanasions I have heard. The other explanasion I have heard that makes some sense is the increased surface area created by the curve. Both of these effects would require that the wetted surface be fairly forward.
It the Master Shaping video Jim Phillips appears to take the concave much further into the body of the board than the standard concave (or teardrop concave). Jim can you expand on why you do this?
Jim has also said here on swaylocks (regarding nose width) that often the wetted surface is much further back than many think and therefore the supper wide nose that many think of is not needed. Further backing your observations from the mag pictures.
<span style="color:Black"><span style="font-size:6px">Howzit J.Troy, Concave placement can be critical. On a board i had shaped in 1980 I had the concave moved back a foot to see what kind of effect it would have. It had an effect alright, as long as that part of the bottom didn't flatten out on the wave it was one of the fastest boards I ever rode. But as soon as it flattened out on the wave it was like a brake,it would literally almost stop and I would be thrown off over the nose every time. Decided to never do that again. I gave it to Ambrose to sell and when ever I saw the board I wondered what the new owner thought about but I never talked to the guy so who knows. Aloha, Kokua</span></span>
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I was told by one big name shaper that part of what makes nose concave help with nose riding is the trailing edge of the concave directing water downwards, and thus an upward force being applied to the nose.
Not down… together. Like the venturri principle… if you squeeze the water together it has to raise the pressure. Pressure, unlike reactive forces, acts in all directions. So if you put a big “ball” of pressure under your board, it’ll push up on it. Kinda the opposite of an airplane wing.
Yes, but as the pressure increases, so does resistance, which will slow you down (plowing water). I think the theories behind this “venturi” effect with surfboards are all skewed. I’m not saying channels and concaves don’t work – I just think that they are thought to be working for the wrong reasons. You can’t place an object in the water and have it constrict water flow without experiencing some sort of equal resistance. And you definitely don’t get any kind of “thrust”. I firmly believe that there is no such thing as a self-jet-powered surfboard ;-).
I like to shape noseriders with belly and no concave. Soft egg rails and extra tail kick.Making the nose wide and fat is up to you.Noseriding is an art form…you can or you can’t.If you can’t the board doesn’t matter.I like em heavy too.
I’m going to have to go with Cleanlines. I made myself an 8’ egg with no concave in the nose, slight concave in the middle and v in the tail. If the wave is right I can noseride the little thing. A couple of times I’ve actually had true tens. (quickly)
I’m making self a 10’0" right now and i’m putting no concave in it. Low entry rocker and tail kick, that’s it.
I read in the last Longboard that Jimmy Gamboa rides a 9’8" with no concave and a flex fin. The cat can hang 'em. I see Alex Knost do it on a 9’2" with no concave and a 17" nose! Goes to show that it’s more technique than design.
Also, I was reading in the archives about big guys not being able to nose ride. One guy even said that over 180lbs. couldn’t do it. I’m 6’1" 200lbs and i can noseride- so there!
Howzit Mr. Clean, My boards have vee from nose to tail. It’s that extra kick in the tail that makes for a good noserider. Aloha, Kokua
Right on Kokua,Seems like the roll or vee gives it some kind of lift.Good noseriders always have their weight off center toward the rail on the wall of the wave.Tail kick works wonders…I really don’t know why though.
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Howzit J.Troy, Concave placement can be critical. On a board i had shaped in 1980 I had the concave moved back a foot to see what kind of effect it would have. It had an effect alright, as long as that part of the bottom didn’t flatten out on the wave it was one of the fastest boards I ever rode. But as soon as it flattened out on the wave it was like a brake,it would literally almost stop and I would be thrown off over the nose every time. Decided to never do that again. I gave it to Ambrose to sell and when ever I saw the board I wondered what the new owner thought about but I never talked to the guy so who knows. Aloha, Kokua
Did the transition blend smoothly or was it abrubpt? Perhaps a minor repositioning OR blending where it begins and ends smoothly.
Howzit Troy, The concave was blended in really nice, it was just an experiment that didn't work out. But if we don't try things , we'll never know if it will work and where would that leave us, back in the stoneage. We learn as much from our failures as we do from the successes.Aloha, Kokua
I went looking at nose riders today throughout Santa Cruz. Bob Pearson boards have concaves up front and are subtle. He blends everything so well that it becomes a bit difficult to tell where one thing starts and another ends, but the concaves are placed in the front 1/4 of the board. Pinched rails, moderate belly roll, and kicked up tails. Huge noses (up to 19 inches on some!)Beautiful boards. The Robert August boards I looked at had the teardrop concave up front. This concave is more abrupt and has far less surface area than the Pearsons. The teardrop concaves are also located in the top 1/4 of the board. Harbour nose concaves are deeper and seem a bit longer than the others. They are scooped out and rather flat, looking like a bullnose countertop at either rail. All of the boards had decent roll in the bottoms and kicked up tails. No hard edges anywhere- most everything being soft and blended. Vee-roll increasing towards the the tail. All very nice boards- all priced around 700-750 dollars.