Hi in the middle of designing my second second home built board, and was wandereing the effects of the wide point forward of center, back of center and center?
heheeheheeee
thatss all smoke for sure :)
thanks for sharing
Yea… that’s a double bump. They can be subtle like that, or more pronounced. Bumps are a little easier to glass than wings with hard corners, but the “release” effect is less pronounced. Based on my theory, the smaller the bump, the more it will feel like a hip… or just an exaggerated curve in the outline. The bigger the bump, and the harder the corners, the more pronounced the release effect.
Regarding the relationship between wing and tail rocker… I’m more concerned with fin placement and planshape when I lay out a wing than rocker. Maybe I’m overlooking something important, but I generally get the rocker how I want it, keeping in mind bottom contours, then lay out my wings. A well placed wing will let me keep my outline more parallel through the middle, and then let me bump down the tail width behind the fins to loosen up (through release) what might otherwise be a fairly stiff planshape. Combine that with the fact that I like my wings/bumps at the trailing edges of my fins, and that’s my formula. What effects my rocker more are bottom contours and overall planshape - curvy vs. parallel - and what kind of waves the board is intended to be ridden in.
Keep in mind, however, that I’m a total hack… and all this might just be smoke!
hey nj ! very clear the way you share your knowledge...thanks for sharing.
I know this topic is about wide point but since you guys talked about wings or bump , could you guys help me to understand the relation of the outline bump and exit rocker ........Usually they break at the same point just in front of back foot....i can feel this thing when I surfing my HPSB......magic power steering....I will be glad to hear you guys thoughts about it...thanks
is this it? googling it per your definition led me to this image :
the double break appear almost imperceptible, like maybe 1/4" or so per corner. i wonder how different a board rides with/without it hmm
edit : image source turns out to be a prior sways thread with your inputs too (http://www2.swaylocks.com/node/1026618). great stuff
cheers,
A bump is just a softened wing… rounded and blended more than a wing, with an outside corner and an inside corner.
I don’t mean to get hung up on semantics, but I have always argued that there is no “pivot point” on a surfboard. There is no “fulcrum” around which things move. Release points, to some degree, become pivot points in that they provide a specific and pronounced location on a board where forces abruptly change. Wings do it best. Here’s something I wrote a while back…
@font-face {
font-family: “Cambria”;
}p.MsoNormal, li.MsoNormal, div.MsoNormal { margin: 0in 0in 0.0001pt; font-size: 12pt; font-family: “Times New Roman”; }div.Section1 { page: Section1; }
"...some people refer to the wing or bump as creating a “pivot point” for turning. More accurately, however, the wing actually serves to create more of a “release point” than a pivot point, by changing the distribution of lift force under or near the back foot. Because most modern surfing maneuvers require the back foot be placed over the front fins for turning, if a release feature (usually a wing or bump) is placed behind the back foot, in line with the trailing edge of the front fins, water will not release from under the board until after it has passed the fins. The rail line through the middle and into the back third is lengthened, and the board becomes more drivey, but less responsive. Wings and bumps are common in wide-tail designs, like fish, and on quads - both of which are known for having heaps of drive (lots of fin area helps, too!).
A hip, or break in the curve of the rail line, is most often used forward of where a bump or wing might be placed. Placed at the leading edge of the front fins, this “corner” in the outline places the release point either ahead of or directly under the surfer’s back foot. The rail line is shorter through the middle, and the board responds faster to rail-to-rail shifts in pressure. Many high performance shortboards use varying degrees of hip in their planshapes. What this design loses in drive it makes up for in responsiveness. That responsiveness is put to use as the rider pumps the board down the line to generate drive, rather than having drive be intrinsic to the design."
thanks nj,
i’m liking the clarification even more hehe mind showing a pic of this design feature (bump) in HPSBs? unless this term also refers to wings on stingers & e-wing bonzers. i’m more familiar with LBs & guns-- though i intend to go into shortboard territory (quad fish, if not mini-simmons hmm) on my next HWS to see how they ride
cheers,
great insight nj, release point.
IMO you’ve just added a valid new entry in the ABCs of board design. if the confluence of the widepoint and rocker apex is a board’s release point, which part of the board would you consider the pivot point-- the center fin, the fin cluster/system, or the tail tip (shape) itself? or wherever the rider’s back foot is placed? i’m scratching my head on this one, in relation to the use of rail “breaks” right past the widepoint, typical in e-winged boards & stingers which are said to help a board release better :
There are a lot of factors to consider, but I like to think of the wide point as being the place where water flow changes… from planing and lift, to release. If the wide point and rocker apex are at the same point, then incoming water ahead of the wide point begins to change into release behind the wind point, particularly along the rail. Putting this “release point” between the rider’s feet creates a more pivoty feel… makes changing direction at lower speeds easier and faster. Putting the release point ahead of center, closer to or under the front foot, opens up the turning radius and generally holds more speed through turns.Retro single fins, guns, fish… all have the wide point ahead of center, and are less “snappy” than the modern shortboard, with the wide point back. Hips on longboards are a different animal… maybe worth a different thread.
Of course, there’s much more to it than this, and this is all determined by the angle of the board relative to the face of the wave, and the plane of the board relative to the upward flow of water on the wave’s surface. Still… if I keep that principle in mind as I lay out template and rocker, it gives me a good “reference point” to design around.
As you may have guessed, center is neutral. Back makes for a more pivoting, more manoeuverable board, front makes for more drivey, front-foot riding boards.
I measure my rail thickness at the thick point. Once the blank is templated, rockered and foiled, the thick point, rocker apex, and wide point are where I want them. When I measure to cut my rail bands, I find the thick point, and make my max rail thickness there. So the foil of my blank and the foil of my rail are basically the same.
Regarding retro fishes… wide points on mine are about 3-4 inches forward of center. It gives me a slightly longer, straighter rail line through the middle and out the back, which is what I’m after. I’ve done fishes with curvy tail outlines, dead straight outlines, and gently curved outlines, and I like the latter the best.
I know fish boards have widepoints farther foreward that 1 or 2 inches. If we’re talking performance shortboards and you move the widepoint up say… 2" , do you move the rail thickness up 2" as well? How about just taking a blank and cutting 6" or so off the nose? Will this have the same effect?
I just flipped through a few aku files f boards in my quiver that work well and the apex is within an inch or 2 of the wide points on all of them.I also noticed that there is a large (almost a foot on average)area where the board stays the same width and even remains within 1/16 of the width of the wide point,so it seems you’d have to really screw one up to get these points so far away from one another that the board just doesn’t work.
[quote="$1"]
I know fish boards have widepoints farther foreward that 1 or 2 inches. If we're talking performance shortboards and you move the widepoint up say... 2" , do you move the rail thickness up 2" as well? How about just taking a blank and cutting 6" or so off the nose? Will this have the same effect?
[/quote]
Some fish have the wp way up, mine don't. If the board's short enough that you can get your front foot close to wp, it'll sort of work. Like I said, this is one of the things we've learned in the last 30 years.... I'm not a fan of ''retro'' fish with wp up a foot. Yeah, I know I'm a heretic. Burn me at the stake.
In response to the second part, the wp, locus of center thickness, and fullest part of rail should not be too far from each other, IMO. And cutting 6'' off the nose can do different things on different blanks; but I think I see what you're getting at. In general, it would shift thickness forward.
The last board I shaped was a small wave board with the widepoint within an inch or so of center, but with a wide tail that kept a lot of area behind the centerline. If you just looked at it without busting out a tape measure, you might think the widepoint was way back. It goes great in the smaller average waves I ride it in.
I’ve often wondered if the wide point and rocker apex needed to be aligned to have a propper flowing board.I have a friend who shaped a few of his first boards,1 being a wide retro fish with no tail rocker,he used the front half of a longboard blank.The board looked like it would be fun and easy to catch waves with all that foam…but it was a dog.He also had a6’9 pin tail thruster single fin with wings and the board really looked the part,but it bogged when paddleing and was really slow with no drive.Now I want to go check these boards out to see if that is the problem because the rails are shaped fine and the outlines look good but I never paid much attention to the wide point vs. rocker apex.
Wide point foreward boards rule.Smoother ,more drawn out turns, float ,paddle better. I know nothing about shaping them but riding them is great.
Don't bring ''rocker apex'' into this, lol, you'll start a poopfight!
I can agree with most of what's been said, but I can add that IMO one of the important things we've learned in the last 30 years is that widepoints around center work best for most boards/surfers. I rarely put a widepoint more than an inch or two from center (I'm shaping stuff under 7'0'', it's actually a % relationship so you could move it more on longer boards). IOW, balanced outlines seem to work best for most applications.
Think of wide point as a symptom, not the disease.
The area with the most floatation is where you should stand if you want the board to trim level.
If you stand in the rear of the board, you can turn it easier, because you are closer to the pivot point over the fins. The farther forward you stand, the more you become an arrow. Weight up front (arrow head) with feathers (fins) in the back. Flies real straight.
Decide where you want to stand when the board is in trim. This is when you will be moving the fastest down the line. Build your design to accomodate this. The wide point is a symptom of the blended curves of your outline.
When designing, start with a board you are already riding. When you are flying down the line, look down at your feet to see where on the board you are standing, and think where you want to be standing. Adjust your width accordingly.
For what it’s worth, my performance boards have the wide point an inch or two back of center. My barrel riders, have it an inch or so forward. More than an inch or two in either direction makes the board feel unbalanced to me. But that’s just for me. as they say on the car commercials, your milage may vary.