Wake surf board rail bands

We have been giving some thought to the way that water interacts with the wake surf board. Hydrodynamics if you will. In the past we’ve shaped elaborate rail bands that followed the outline of the board. Tracing outlines that curved along the rail line and shaping to that curve. Then we thought, what purpose does that serve? There really isn’t any that we could think of that couldn’t be addressed by just creating a straight rail band, save for the nose, which curved inside a straight rail band. From a production stand point, a straight line would be much easier to cut and shape than a curved rail band. In looking at the amount of material that would be removed, it also seemed that it would reduce weight some and remembering our thickness = stiffness formula, using a straight line as the rail band would give a fairly static stiffness through the wake surf board where the riders feet are. At least that is what we are theorizing.

Water wraps curved surfaces, so the rounded rail on some wake surf boards create water attachment. Now that may sound bad to some folks, but it isn’t, by and of itself. A shaper may want the water to sort of GRAB the wake surf board in that area. It will increase drag and also that grip on that section of the wakesurf board. So, does water extend up onto the deck where the rail bands extend? Nope, it will wrap the curved surfaces, but eventually releases once that curve doubles back and starts to go flat. The next time you are out wakesurfing, you can observe this by looking down to the rails of your wake surf board. If you watch, you’ll see the water relaesing off the sharp or hard part of any rail, and wrapping up somewhat over a curved surface. Does the water double back and flow towards the center of the wake surf board? Nope. It would be cool if it did, because you’d have the ultimate grip!

That being said, the deck side of the rail bands should be shaped to help equalize the distribution of the stiffness through the board. We want to keep the area under the feet flat or flat’ish to better aid transfer of energy from the feet, but also to keep that stiffness very uniform through the area of the board under the wakesurfers feet.

Ok, so here’s what we are doing with our rail bands. You can see that they are basically straight and parallel to each other. The area under the riders feet will be mostly flat’ish

Deja Vu! Ok, we told you that we screwed up and didn’t get any pictures of some of the shaping, but you can see with this picture that we’ve foiled the deck and the rail bands down to the rails themselves.

Now that the core is principally shaped, we’ll thermoform the deck skin to mostly fit the shaped core and vacuum bag the deck skin onto the core. We hope you’ll follow along!

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