We had fun documenting the wakesurf trick and put off the continued documentation of the reverse camber springer build. We’re actually a little further along than we have documented, which is common. We build and THEN document. 
We’ll show one picture that we planned to include in the documentation process and then start talking about our discovery so far.
Now what we had planned for the springer wakesurf board was a single piece of 3mm corecell sandwiched between two layers of 6 oz carbon fiber. Now most of us associate carbon fiber with being stiffer than steel or titanium and in relative comparison it is. But just how thick is this 6 oz layer of carbon fiber? It’s measured in thousands of an inch and the truth is that in thicknesses like that, where we are talking .0080 or whatever after consolidation with the vacuum, it’s just not all that stiff. It’s like talking about the properties of aluminum. Super stiff and lightweight at 3mm, but aluminum foil? Not so much. Although we’ve wrestled with those stupid cutters on the box before!
As we completed the glue up of the core and pulled it from the bag we had this vision of a super “twangy” wakesurf board with this springer that would just blast someone out of a turn or loft off the lip. In short: it’s not. It’s stiffer than plain foam, but not a whole lot, plus being mostly down the center the increase in stiffness in that select area really seemed to promote twist off at the rail line. One of the issues with R&D is that sometimes you solve one issue and create a new one! So while this springer concept seemed to offer a tiny bit of more “twang” it wasn’t that much more than just plain old everyday foam, but what it offered in terms of longitudinal stiffness it also directly increased the tendency for the blank to want to twist up at the rail line.
We know that you simply love our amazing drawings! So here’s another. We’ll try and explain with the visual aid, what’s going on with the forces and how that impacts the design considerations.
So in the first segment of the wakesurf board picture, where you can see the rocker and the reverse camber springer it’s easy to see that the springer, if adequate, will resist the forces applied to the length of the board. That’s certainly a cool concept, but does resistance alone eliminate the forces? Now, like water or electricity those forces will seek the path of least resistance and for our wakesurf board design that would wind up being the out and along the rail, twisting the area just behind the nose UP and associated with that, is the rail line along the tail area, diagonal from the nose area would get pushed down. So THAT isn’t a benefit! Any configuration that hopes to utilize the springer as an enhancement has to manage the transfer of the forces off to the rail, or it just increases the sponge out.
Our design didn’t encompases this consideration, so we are setting this build off on the back burner for now while we contemplate how to address this energy transfer that winds up creating the rail twist off.
As we sit here and think about the concept, a tiny bit of flex is a really good thing. Well, not the flex, but the flex return is the key advantage. Loading up the board and having it unload in the direction of travel is what we are trying to achieve. What comes to mind, immediately is that the springer isn’t as effective in controlling flex and spring back as would be “something” along the rail line, or somewhat inset on the rail line. It would seem that over the 20 inches of a typical wakesurf board, the twist off AND longitudinal forces could be managed easily with either a rail line enhancement, like our carbon fiber wrapped rails, or possibly something inset somewhat, like splitting the wakesurf board every 7 inches or so lengthwise, thereby creating three segments. If they were curved and sort of blended into the outline, it would provide resistance to twist off and the longitudinal forces along the length of the wake surf board.
Anyway, such is the deal with R&D! Thanks so much for following along with…what, our failure to anticipate the design requirements? Anyway for following along, we do appreciate it!
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July 22, 2012 at 2:30 pm (UTC -7) Link to this comment
We’ll start this tail block glue up by assembling all of the pieces and also our core. You’ll note that the deck side of the core is still unshaped at this time. We use a one pound density foam and it is very floppy when shaped down to the dimensions of our wake surf board. Once the rail material is attached we’ll gain some rigidity, but until then, it’s almost impossible to shape accurately. So, we’ll leave the deckside shaping until we have some added rigidity along the rails of the wakesurf board .