Authors: Flyboy Wakesurf
We want to jump ahead in our build discussion, for a moment, just to keep you on your toes! Actually, no, we ran across a discussion about the concept of the center of mass over on Swaylocks, and we thought it was timely. Surfboards, from which surf style boards were derived, have always been tail heavy. The fins are back there, traction pads are back there and the nose of surfboards are thinned out and then curved to a point. We say “always” but that isn’t true, lets say the modern high performance shortboard that most folks are familiar with. More weight and volume in the tail and less weight and volume in the nose, would necessarily, shift the center of mass or the balance point back behind the mid point of the length of the board.
Now that isn’t a bad thing. The most common length of an ocean surf board is 6’2″. AND there was a tendency for that balance point to fall somewhat close to the rear foot. Not right under the rear foot, but closer to the rear foot than the front foot.
As wakesurf boards developed and we took our basic shapes from those ocean boards, that center of mass or the balance point shifted even further back towards the rear foot, as we shortened the length of our boards. Less length and less mass forward, would cause that balancing point to wind up way back by the tail and the fins and boxes and traction pad. Again, that isn’t a bad thing until you are forced to ride it like a non-directional skimmer.
Skim style boards, almost by design have a center of mass and balance point that is almost perfectly centered between the riders feet. The construction is uniform through out and so the weight or mass is distributed evenly. Out in the ocean skimmers are tossed along the inflow of the waves basically in just a fraction of an inch of water and are sort of slid out into waves in all manner of directions. Nose first, sometimes sideways we’ve even seen shuvs into the wave before it arrives. That’s how the boards were designed. Surfboards don’t have that uniform construction. They are foiled with a thin nose, thicker tail, plus the entire fin pod hanging off the back. We want to show you some amazing artwork! We know it’s been ages since you were treated to this stuff, so here is a visual depiction of the balance point or center of mass of a typical surf style wakesurf board.
We TOLD YOU it was amazing! You can see the black areas represeting the fins and kicktail of the traction. Under the fins are also fin boxes and the attendant resin to stick them in the foam. Also, the tail is typically thicker than the nose and while you can’t see the outline, you know that the typical surf style board has a directional shape with a point nose and a wider’ish tail. Not a non-directional skimmer sort of design.
We had wanted to reference the discussion over on Swaylocks, but that site seems to be down at this moment. If if starts back up, we’ll revise this article to link to that discussion. Anyway, in short someone was asking about the center of mass and where other shapers tried to locate it. One knowledgable shaper chimed in, don’t worry about it, because…you will ALWAYS be ON THE BOARD and since it’s light weight, the rider can just change the angle, or direction and not have to worry about where that center of mass is. AND that is the general assumption of surfboard shaping. YOU as the rider are on top of the board at all times and so it doesn’t matter where that center of mass is, because you clearly outweigh the board and can just shift your weight.
EDIT: Sways is back up! Ok, so here is the link to that thread.
Here is the quote we referenced and THIS is generally accepted within the surf community, it’s not a singular opinion nor was this questioned by anyone:
I don’t think you should go crazy over the CoM location. It’s not a plane. The board isn’t really massive; you’re not fighting the effects of mass on a shortboard. The nose is light, and it’s short so the torque/moment isn’t an issue. You’re not trying to balance anything. You’re on the board, so you’re gonna force it into the proper orientation regardless of where the CoM is.
Right? EXCEPT when you’re forced to ride your board like it’s non-directional, right? Because then you aren’t always on the board. In fact when the focus of the tricks on your surf style board HAVE to include a shuv or shuv variation tricks, you damn well better be concerned with the center of mass and the balance point. Counter to the author where he says your board isn’t a plane, mid shuv it IS a plane!
Do you flowboard, skateboard or wakeskate? All of those sport disciplines rely in non-directional boards and the basis for their tricks are shuvs and variations. Does the equipment used in those disciplines have weird and wild weight distribution towards one end? No of course not, for the most part all of the equipment is pretty equally balance. There are deviations, longboard skateboards for example, so lets refine that statement to that equipment where shuv based tricks are predominant. That equipment is pretty much 100% uniformly balanced in the middle of the board.
It makes sense, the designers want to boards to rotate in a nice tight uniform pattern. What would happen if there was significant weight distributed towards one end or the other in that equipment? The shuv based tricks would sort of wobble as the heavier end would pull the rotation away from the rider. Also, there would be a tendency for the heavier end to want to hang down, preventing a flat rotation, due to the effects of gravity. Unless of course you think gravity doesn’t exist.
Let’s just accept that as anecdotal evidence for this discussion, other sports that focus on non-directional riding and shuv based tricks TYPICALLY use equipment that is unform in weight distribution creating a center of mass or balance point that is between the riders feet.
Surf style boards sure as hell ain’t that! BUT and here is the kicker, some folks that couldn’t tell you the difference between a chunk of PU foam and a chunk of XPS foam, decided that riding surf style boards like they were non-directional was the SHIT! Lordy.
Now that we it’s purely evident that you simply have to ride your surf style board like it’s non-directional, you damn well better have one that helps you ride that way! If you don’t have a back big, and shuv-in, shuv-out combo, you’ll always be in the audience looking up at the podium in the surf style divisions.
So we made some revisions to the flyboy over the last few years. We started the process way WAY back in the day with Dennis Horton, and we think it was his idea. He is the current EWT chief judge and we think that he is in charge of sales for The Walker Project. He has some offical duty there.
What we did, way way back then was attached some wheel weight to the nose of the board to try and affect the balance point. We didn’t realize at that time, that wasn’t the point. It wasn’t add just enough weight to change that balance point. It was this concept of the center of mass. Wakeskates, flow boards, skateboards, skimboards all have it, because of…uniform construction and uniform distribution of weight and mass throughout the equipment. Skateboards are a little off, because of the trucks and wheels, but they are uniform in that they have an offsetting pair on both ends. What is useful is that mass winds up being uniform over a very small piece of equipment.
When we did our experiments, placing the wheel weights way out at the end sort of balanced it lengthwise, but not sort of widthwise, nor was it in close to where the forces applied would act on that weight. It reminded us of that olympic sport the hammer. All the weight way out on the end all the force way out on the other end!!!! So what we found, to get a more uniform rotation was to shift some of the mass under the riders feet. Here is MORE AMAZING ARTWORK that sort of gives a representation. It’s not really what we are doing, but it gives you the concept.
It’s creating more uniform weight distribution towards the middle of the board, between the riders feet. The idea being to create a center of mass and balance point such that when the surf style board is forced to be ridden non-directional, you get that rotation where you want it! Not spiraling way out of control.
Short video of James landing a front big and back big from an IG edit and a week or so ago.
For our mobile enabled friends here is a link to that video of James Walker landing the front and back big on his newest Flyboy, if the embed above doesn’t work for you.
Ok, we should add that you can sort of move the center of mass with stumpy nosed boards, It leaves volume and weight way out at the nose. It still requires that they be shaped like bigger boards and they ride that way. The concept is shape a 5’4″ board like a normal surf style board and then hack the last 6 inches off. The rest of the outline is still that 5’4″ board. BUT, it is effective in shifting weight forward and changing the center of mass along with it. We made shorter boards, to beign with, because we thought the 5’4″ boards rides sucked out loud and still do.
So we had to address this forced requirement where judging in the surf style divisions only rewards bards for being ridden against what they were actually designed to do. They have to ride more non-directional, against their very design! But we also didn’t want to give up the quality ride associated with a surf style board. Longer and stumpier reduces that, in our opinion. They ride like longer boards and as we mentioned the other day, prevent you from tucking in closer to the wake face.
So, we balanced the mass instead! That was a bunch to read! We really appreciate if you made it through all of that, it was a lot to take in. We’ll talk more about all of this, is smaller bits, we promise, as we begin documenting the build.
Thanks again for following along, we really appreciate it!