Assuming two identical boards and you cannot change any specs on them - not even fins (semiguns made for Southern California). One has a double concave through the fins and the other one a very slight vee bottom (vee through the tail). How would these boards differ from each other performance wise?
Thanks for the info.
Hey MACSD, I’ll let those with more experience correct me if I’m wrong and I’ll learn something, but I’ll offer some basic tendencies. The board with the simple paneled vee will ride deeper in the wave face and want to climb the wave face less than the double concaved affair. If the vee is the same in both boards the one with concaved surfaces would have to have a little more tail rocker to start before the concaves were worked in to make it comparable to the one without the concaves. The concaved board would be much more dynamic off the bottom and be lighter in the water when turning. There some real pro shapers on this forum that can define things more accurately and shed more light on the subject than I.
Gone Surfin’, Rich
Thanks Halcyon,
Which would you prefer on medium size powerful waves? Is it safe to say that the board with vee would give you a more neutral ride?
top
Hey MACSD,
All other things being equal, how deep the vee is has everything to do with how the board will surf.
After the vee is cut into the tail section the concave is fashioned into the board. How deep the board rides in the wave will depend on how steep the vee is cut. The rails may be level with the center of the panels or below them depending on the depth of the vee. Without the concave the board will not have as much lift as you turn it. IMHO with the vee very slight the board would handle very nicely in medium sized surf and be very responsive. It would have more lift and drive if some concave were put in the panels but if you keep the apex of the vee rather flat and put concaves in the board will become somewhat unstable as waves start to become more critical. So with concaves in the bottom of the board I would say that you would want slightly more rocker and vee in the tail to start with before the concaves are fashioned into the board.
Note: If a pro like Jim the Genius were around he could most likely summarize all this in a phrase.
As the modern shortboard was beginning its evolution the value of a paneled vee tail was demonstrated beautifully when M.R. and Cheyne had the whole world of surfing in their hip pocket for over four years. There were no concaves on the tails of they’re boards though the entry of M.R.'s boards were concaved. I think all Cheyne’s boards were McCoy’s loaded dome, which is a graduated convex surface that is steeper in the nose and tail than it is in the mid-section. I could be wrong on the configuration of Cheyne’s boards but he might let us let us know what the reality of things are if he checks in on this thread.
Off to work, Rich
p.s. Subtle lines work best.
The loaded dome is MUCH newer than those boards when Cheyne and MR were on top of the pro surf pack. Our local shop has a vintage Horan pro model (McCoy with the checkered deck), it is a very simple and modest Vee bottom, with no DOME at all.
The tail vee is there for stability and control. The concaves are there for throwing the board through hard turns. As you push into more and more challenging big waves, almost all riders turn to Vee or domed bottoms (here’s where someone posts Dickie’s opinions on concaves and big waves). I don’t like concaves in any size wave in which I am not pumping the rail fins for speed. My preference for 10ft (HWN) plus waves is reverse vee, although many others deepen the vee through the tail (Jeff Clark does domed bottoms in which the doming deepens through the tail).
And in between, like a semi-gun, if you value pumping it through turns for speed, I’d lean towards concave. If control is more important, Vee.
Ditto Blakestah…Vee is for control in power…concaves are for lift and speed
Concaves for lift and bite in the turns, not speed!
Fastest ANY kind of board is flat to V, in every case!
Now someone is going to counter by saying a 18" wide mini gun, flat to V, is NOT fast in 1-3’ mushy waves. Whatever…
All you guys who THINK your fish is the fastest ever, try dropping in on a TOH wave that goes somewhere. All that flat rocker just sticks, the width is pure drag, and you can barely make the drop!
Fast always has to have a medium stated, as nothing is fast in every condition!
What if you have both?
Spiral Vee on a Thruster, alot of vee alot of concave.
…cheap mans bonzer??
Get good bite.
Lose out on quick response, rail to rail, and also nose to tail.
Part of the reason we like short boards is the quick response time.
FinianMaynard’s, AND TheirryBielak’s record speed windsurfers, going around 54 mph for 500 meters distance, happen to both be double concave forward, but at the waterline when riding, pure accelerating V to an imperceptable tail rocker for clean water release when the nose comes up.
Hey there everyone,
LeeDD I agree with you, but I want to point out that a windsurfer board is flatter on entry then a shortboard and needs hardly any tail rocker do to the push that the wind is giving it. They are also 4 inches thick, if not more. I like my board with vee and double concaves, you just cant beat the system. I have been working a single concave running thru out the bottom of my longboards (about a 1/4") and an 1/2" tail kick and having a great time on them.
Speaking of vee vs. 2x concave… heres a few shots of an old board project. Its 6’ long x 19 1/4" wide x 11 1/2" wide nose x 15 1/2" tail. I made it for a good friend in the summer of 1990.
The bottom contours blend from 1/4" deep vee in nose/entry down through a 1/4" deep rail-to-rail concave running to just behind center, then to double 1/4" concave vee bleeding through the fin cluster, and out to flat tail kick in the final few inches. Low rocker… about 5" in nose x 1 1/2" in tail, 2" thick, flat deck, full tucked rails, except for rear 12" which tapers down to a thin, resin edge. Glossed and polished.
The board was an attempt at translating some of my triplane bodyboard bottom contours to (more subtle) surfboard form. Built for fast, down-the-line surfing in clean waves under 8’, rather than quick, vertical maneuvers. A successful project.
The deck`s “Doc Model” logo character (a spoof on me) and lettering were applied by brush directly to fine-sanded hot coat with india ink and acrylic polymer.
http://photothru.com/photo_filedb1/A5/E7/E4/A5E7E4/viewable/A5E7E4_131CD443036_1.jpg
http://photothru.com/photo_filedb1/A5/E7/E4/A5E7E4/viewable/A5E7E4_131CD442E51_1.jpg
http://photothru.com/photo_filedb1/A5/E7/E4/A5E7E4/viewable/A5E7E4_131CD4438A7_1.jpg
http://photothru.com/photo_filedb1/A5/E7/E4/A5E7E4/viewable/A5E7E4_131CD443A4F_1.jpg
http://photothru.com/photo_filedb1/A5/E7/E4/A5E7E4/viewable/A5E7E4_131CD443594_1.jpg
Dale,
That’s a cool logo and lettering!
Is it just me or does that board have alot of toe in on the fins??
Kind Regards,
Matt.
Rocker…the most critical feature…one of the most overlooked features of concave is that it reduces rocker…a deep single concave makes the centerline/stringer rocker flatter which is faster…plus you get all the other bennies mentioned already. A double has flatter rocker in its trough…
Matt S, nice photo edit. All that extra toein is for control and improved turning on a wide, low rockered board…1.5" tail rocker is low = fast. That toein is probably 5/16 to 3/8…validates my recent lesssons…rocker and toein are interrelated…
Matt.S
Yes, it likes to be wound up… the owner and I have discussed modifying it w/an adjustable (toe-in) fin system. Thanks!
meecrafty…
You are correct. The entry vee disappears into the mid-section concave. Through the deepest portion of that single concave, the centerline/stringer rocker is flat for about 16", directly under the rider`s stance. But the rail lines on either side of that area have slight rocker.
If my friend had wanted more of a vertically-oriented board, I would have increased the overall rocker (esp. in tail), moved the fins up, reduced the toe-in, thinned out the thickness in the front 1/3… shifting the bulk of the foil back, and made the rear 1/3 thicker w/ blunt rails.
I’ve noticed that concaves really don’t help when it gets heavy. I find myself fighting to maintain control. Fun for small hollow waves though.
Reverse V is what I had planned for my winter 7’6". Anyone have a good understanding of where to begin, end, and blend? I’d like to get my hands on a Maurice Cole model just to eyeball it.
