NSS Type Wakesurf Design

[High Altitude]

Tao,

Can you describe how the nylon washers are used as well and how they relate to the "ice cream sandwich" of three boards? I think I understand but would like to make sure. Any chance you snapped a few photo's as put the whole thing together? I have looked thru the entire thread and didn't see anything.

Looks like the wave has more push than the old leaned one. The guy surfing on the original video had to pump quite a bit to stay in the pocket. Seemed a lot less effort in the NSS vids. -Marc

[Tao of Wake]

Unfortunately, I didn't snap any pictures of the disassembled parts. The nylon spacers are 5/8" long and are between the two outer boards to keep them that far apart so that the inner board can move between them. Don't think of them as washers. Think of them as cylinders. You will find these at any of the big box home improvement stores or a hardware store. They are called spacers. The ones I got are just big enough inside diameter to fit over the 5/16" lag bolts and are 5/8" long. Because the HDPE I used is 1/2", there is about 1/8" of space between the inner board and outer boards (probably a little less since the lag bolts likely compressed the spacers some). The inner board has grooves cut out where there is a bolt so that it can slide in and out. The grooves are just bigger than the outside diameter of the spacer. The only thing attached to the inner board is the actuator.

The reason I have two outer boards is because I didn't want the inner board to be scratching the hull as it moved. Also, it seemed like it might be a little more stable.

Definitely more push with the NSS. One time I fell back in the white wash, and I was still able to pump back into the wave!

Edited July 24, 2013 by Tao of Wake

[High Altitude]

Ah...spacers. That makes more sense than what I was thinking about.

How did you make your holes in the plate? It looked like you drilled and then did some cutting...maybe using a jig saw? I assume the cuts are just slightly bigger than the width of the spacers so there isn't too much play in the whole thing.

Also, can you explain the lags? It looks like they go thru the entire three layers. If that is true, what is the overall length to give you 3/4 inch inside the fiberglass. Also, did you use anything in the holes when sinking the lags?

Sorry for all the questions but you have set the bar pretty high! -Marc

[Tao of Wake]

Ah...spacers. That makes more sense than what I was thinking about.

How did you make your holes in the plate? It looked like you drilled and then did some cutting...maybe using a jig saw? I assume the cuts are just slightly bigger than the width of the spacers so there isn't too much play in the whole thing.

Also, can you explain the lags? It looks like they go thru the entire three layers. If that is true, what is the overall length to give you 3/4 inch inside the fiberglass. Also, did you use anything in the holes when sinking the lags?

Sorry for all the questions but you have set the bar pretty high! -Marc

No problem regarding all the questions. I am more than happy to share my design!

I cut the holes using a 1/2" paddle drill bit (that was just bigger than the outside diameter of the spacers) at either end of the channel and then used a RotoZip to cut the channels. It was a bit dicey cutting freehand like that. The channels do not have perfectly straight edges like I would have wanted. I still have enough of the HDPE that I may redo both using a router. But maybe not! No one ever sees the channels because they are only exposed when the gate is extended (in the water).

Yes, the lag screws go through all three layers. I used 5/16" x 2-1/2", so they should have gone 7/8" into the hull (assuming the spacers did not compress at all). I did put 3M 5200 marine sealant in each hole in the hull.

[High Altitude]

Did you use a torque wrench or just tighten the lags by hand? Also, what size drill bit did you use on the fiberglass before sinking them? I have found putting lags in fiberglass to be fairly stressful...both on myself and the actual fiberglass! Having the correct size hole must be the key. Luckily, it will all be covered so it's not a big deal if it's not perfect (it will also cover up my gel coat damage from the original surfgate design) -Marc

[Tao of Wake]

I used an impact wrench to tighten the lag screws. As soon as the head of the screw was tight against the top board, I stopped. I don't remember the size drill bit I used. I just found the one that was about the same size as the base of the lag screws (the solid part minus the threads). I just eyeballed this.

Yeah, I had the same issue - covering up what I had already done to try to build a surf gate system. Before I started with this solution, though, I filled the previous holes with Water Weld, let dry, sanded them down, then lightly painted them with black gloss paint that matched the hull.

[edsvlx]

Wow really great job Tao. Really like what you did. The ideas just keep getting better.

[Ndawg12]

I was able to get out and test last night after the rain stopped, but I couldn't ride it because my wife wouldn't pull me. She didn't want to miss watching Batchelorette!

Here is a video from last year of the wake while listing the boat:

If I remember correctly, here is how it was setup:

Bow: 450#

Center: Stock 500# full

Rear: Surf side 250# stock + 750# sac

Wedge: All the way down

VAB: 4 guys totaling about 750# all on surf side (including driver)

Fuel tank: ??

Speed: 11.2 mph

Here is a pic of my prototype NSS:

You can see the holes where the screws were and then I had the knobs that could be tightened and loosened by hand. The middle board could be pulled out and then up or down to test different configurations.

Here is the fully automated system on the boat that I tested last night:

I mounted the actuator to the underside of the swim platform where it is reinforced (thicker) just behind the support bracket. There are three "plates" with the middle one that moves in and out by the actuator. The bolts are 5/16" x 2-1/2" going through all three plates and into the hull. There are nylon spacers between the top and bottom plates that are 5/8" so that the 1/2" center plate is free to move. As you can probably see, I didn't have much room to mount the actuator due to it's size and the swim platform bracket. If I ever do need to remove the swim platform, I would have to disconnect the actuator, but that is easily done with the nut/bolt on the one end and the pin on the other.

I am using the Lenco control:

And the Lenco 102 actuators (4.25" stroke):

Here is a pic of the wave (sorry for the poor pic; I was trying to drive the boat and take pics):

Here is a quick shot of the gate, too:

There is some water coming over the top, but it doesn't seem to be interfering with the wave.

Here is the setup for this:

Bow: ~300#

Center: Stock 500# full

Rear: 250# stock + ~600# sac both sides

Wedge: All the way down

VAB: Just me driving (so on surf side)

Fuel tank: 1/4

Speed: 10.8 mph

I can't wait to surf this!

I'm in the process of doing a very similar system, I've got most of my material for a manual setup for now, 1/2" PVC sheeting, 2 1/2" lags, and 5/8" spacers. What are your thoughts on the curvature of my transom? I'm thinking I need to raise my platform up 2-3" in order to get the top edge of the fin closer to the "step" in the hull. You can see how the OP's swim platform is much closer (sits right under it) to the "step" than on mine. Raising the platform should also give me the diagonal 14" that I need to mount an actuator in the future. Thoughts?

Edited August 1, 2013 by Ndawg12

[Tao of Wake]

I'm in the process of doing a very similar system, I've got most of my material for a manual setup for now, 1/2" PVC sheeting, 2 1/2" lags, and 5/8" spacers. What are your thoughts on the curvature of my transom? I'm thinking I need to raise my platform up 2-3" in order to get the top edge of the fin closer to the "step" in the hull. You can see how the OP's swim platform is much closer (sits right under it) to the "step" than on mine. Raising the platform should also give me the diagonal 14" that I need to mount an actuator in the future. Thoughts?

I don't think you will need to raise your platform. The gate may not need to extend to the top of the water. Mine is definitely below the top of the water (when all of the ballast is full). Because of the angle of the hull, and therefore, th angle of the gate, the water is forced upward. This causes some spray, but it also disrupts the entire wake.

[Ndawg12]

I don't think you will need to raise your platform. The gate may not need to extend to the top of the water. Mine is definitely below the top of the water (when all of the ballast is full). Because of the angle of the hull, and therefore, th angle of the gate, the water is forced upward. This causes some spray, but it also disrupts the entire wake.

Not really trying to gate to the top of the water, just trying to utilize as much of that space as possible...if you think it will maximize the effect on the wave.

[Tao of Wake]

Not really trying to gate to the top of the water, just trying to utilize as much of that space as possible...if you think it will maximize the effect on the wave.

I'm not sure if it will have a significant impact or not as I didn't test that. If your swim platform is just underwater when you have all your ballast full, that is the same as mine. Therefore, if your gate is just under your swim platform, it would be the same as mine and should function similarly.

[Ndawg12]

I'm not sure if it will have a significant impact or not as I didn't test that. If your swim platform is just underwater when you have all your ballast full, that is the same as mine. Therefore, if your gate is just under your swim platform, it would be the same as mine and should function similarly.

Gotcha, I was looking at it again last night. I don't feel comfortable trying to mount something flat against that surface. The radius of the curve in that corner seems too large on my boat and the mounting screws may have to be too far in towards the platform mount and thus less travel for the sliding gate to get at least 1.5" out past the edge.....sorry, hard to put into words...