10K Lakes Open Prelims and some wakesurf board molding

Well, if you got a chance to watch any of the prelimins from the 10K Lakes Open you’ll notice that most everyone was struggling some with the G23 wake. Looks like it wound up somewhat soft and it would appear there is a prounounced trough. On the live broadcast, you could hear the crew telling riders that everyone was having trouble and they’d have the wake fixed for Saturday. That typically comes from too much weight, which is really common in these big boats with total surfing weight in excess of 8,000 pounds. From wht we hear at the contest site, the organizers are on it and will be working on refining the wake for tomorrow’s contest. We really like that concept of looking to see what was actually landed during a contest as a way of determining the quality of the wake. We haven’t seen any standup runs so far, everyone seems to be using their four falls completely. We’re looking forward to a reduced trough and less soft face for the finals. It looks like James is seeded second in the men’s pro surf and third in the men’s pro skim. With the wake changing today, it will be like starting all over again. The practice sessions and prelims won’t allow the riders to bring much “experience” forward. We’ll keep our fingers crossed that the wake is significantly better than yesterday and that James is able to figure it out quickly. One thing that James is known for is figuring out even the most difficult of wakes and bringing his best to the contest! Hopefully the wake will allow them to throw all of their tricks and not just a limited set!

We should mention that we heard the streaming video was in fact LIVE and it was shot with an iphone! The feed looked great and the sound was a little too good, you could hear the judges talking. Anyway, live broadcasting is as simple as a ustream account and an iphone!

James was able to land an ollie 7 and surface reverse, but the air 180 to 5 wasn’t completed and he didn’t even attempt a big spin. Keenan landed an air reverse and attempted a big spin and riverdance, but the wake did prove a little soft for those tricks. James also is riding in the men’s pro skim and he opted to change and ride an Inland Surfer Contagious, as we mentioned he’s not liking the traction on his new skimmer.

James did land a drifter and a frontside surface 180, plus numerous shuvs and he tried a 3 shuv and front shuv, but didn’t land those.  We expect to see James Walker in the finals in skim and he certainly will be in the finals for men’s pro surf. We aren’t quite sure how folks are advancing to the finals, if it’s everyone then well..duh! Of course James will advance.   There were 5 or 6 entrants in the men’s pro skim, so we’ll see if he made the cut there.

We wanted to talk some more about wakesurf board molding and in particular a concept referred to as a partline. Molds can be developed in several styles or flavors. One style is a two part or multiple part mold where the part being molded might have a complex shape. It’s possible to mold just about anything and deep undercuts or significant curves are achieved by developing multiple piece molds. Imagine that you are trying to mold something like a right angle of a pipe. If you merely poured some liquid epoxy into the mold you could actually create the part, but how would you ever get it out? It would be impossible without destroying the mold unless the mold split into two pieces, either at the angle or alternatively with a top and bottom half of the mold. In the example of the pipe, if we look down on the circular portion, there is an undercut for the bottom half of the circle. If we place the split or partline at the apex of the circle, looking down, then for each half of the mold, there is no undercut.

Just two semi-circles, joined at the wide part. That is the premise for making two piece molds or even a multi-piece mold with a larger number of pieces. While not common, three, four or even five piece molds are possible.

In looking at a wakesurf board, it would seem the easiest way to develop a mold would be to split the mold into two pieces, top and bottom, along the highest or widest point along the rails. This incredibly amazing hand drawn picture gives you an idea where most folks would deem the best place to split the mold, that split being referred to as a partline.

In the picture, it’s drawn to resemble a slice of the wakesurf board and you can see a bottom concave and the left side rail with the apex of that rail. If the partline is put there, we clearly can avoid any undercuts that would prevent the mold from splitting. Can you see another problem with that idea?

This is the sort of thing that causes issues for mold makers and designers, as a mold maker you’d need a really good idea of how the final product works to understand that the rails of a wakesurf board undergo the most force on the entire wakesurf board. Knowing that little bit of information, would you want the partline there? NO! The reason being is that when you go to load the reinforcements into the mold, guess where at least some of them are going to stop? Right at that partline, so if we were to have two layers of reinforcement covering the rails, one from the top and one from the bottom, one of those layers is going to wind up stopping right at the part line, or in effect at the highest point in the rail. One side of the apex will have two layers and the other would have one layer and there would be a a split right down that line. It will become a weak area and prone to failure.

In designing the partline, it would be most beneficial to move that split out and away from the rails all together.

So let’s propose a different part line and as students of wakesurf board molding you immediately recognize the issue with the undercut and question how we’ll remove the mold and the molded part.

Ok so you can see that the partline is at the very bottom of the rail, at the point where the bottom intersects with the rail. The Flyboy Wakesurf board has a slight undercut, but it’s a crisp line where that meets the bottom. Ok so you can see that by doing this, we can achieve a few things. One is that for a solid core mold, we can actually fully lap the rails. This is consistent with the most common manner of constructing wakesurf boards and moves the split from the of the reinforcement to the normal areas, which are top and bottom of the wakesurf board a little bit off the rails itself. We intend to achieve that by splitting the top mold into two pieces, at the wide point of the outline. Here is what that will look like, in this, another amazing drawing!

You can see that there is a horizontal line across the drawing where we intend to split the top part of the mold. So there are two parts of the top mold and those slide together to form a single unit and they will join at the wide point of the wakesurf board. For a hollow build, the reinforcement will be laid into the top portion of the mold, which is upside down. That reinforcement would be left long so that it flips up on the flange a bit. We would presume the use of a bladder and that would then be placed inside the top part of the mold cavity. Once the bladder is in place, the excess reinforcement would be flipped inward ontop of the bladder. The bottom part of the mold would have the reinforcement trimmed flush with the edges and when the bladder is inflated, the excess reinforcement from the deck would lap the bottom. We’d also expect to build up the rails somewhat internally, with some tape that just reinforced the rail portion from the inside.

In a solid core molded board, the same concepts would be used, except, the top of the board would almost be fully laminated before connecting the two deck side pieces. Another option is to preform the skin and then glue the cured skin to the core in a secondary molding step. The point being that the mold will be quite versatile and will allow us a number of building options. We can use the mold halfs to preform skins, attaching them to each other for a hollow construction or a chambered construction, or to a solid core.

Fun huh? We are excited with the concept of wakesurf board molding and hope to have some great articles as we work with construction technique!

Thanks so much for following along and let’s wish James good luck at the 10K Lakes Open in the finals!

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