Custom Surf Platform build

I thought I'd post a formal thread on this project.

My buddy "Phathom" (Desi) is doing the work, and together we've been doing lots of planning and measurements. Our objectives have been to get something with a SMOOTH bottom that doesn't have a huge lip that digs into our surf wave. We also wanted something that was as narrow as possible relative to the surf wave without changing the platform bracket location. We chose to add a little length to it to make it more user friendly.

Here's how it's looking so far:

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Still have to sand down more(possibly) and coat the bottom. It's all cut, sanded and coated on the top. It is measuring 62" at transom, 14.5" deep the brackets, 13 3/4" long angled transition, and a 43" wide platform end that measures about 23 7/8" long transom to platform end all at 7/8" thick.

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It's made out of two pieces of plywood sandwiched together, because that's the wood we had laying around. Spray on undercoating to cover it, again because we had it laying around. If we like it, we'll make one out of a single thicker piece of wood, glass in the wood and put some closed cell foam decking pad on it.

My outer brackets were pretty wide, so we did what we could on width as I didn't have much of an interest in moving them or making new ones. (thanks for the welding offers though). I should have to cut off about 1.5" of the extisting outer brackets though. But it's the flat bar before the angle brace comes in, so it shouldn't affect things much. Not sure if we'll have to shim the new platform up or if it'll be thick enough to match the height of the existing as is.

https://lh6.googleusercontent.com/-_...233806_076.jpg

I did a drawing of the dimensions. The platform brackets are in orange. they overlap our platform a tiny bit on the sides, but should we go with a full blown version, it'll be easy enough to chop 1.5" off the ends of the brackets that extend past the angle brace as mentioned above.

https://lh3.googleusercontent.com/-L...Dimensions.jpg

Pictures of the OEM Platform for reference:
https://lh3.googleusercontent.com/-y...812_115954.jpg

https://lh4.googleusercontent.com/-4...812_120019.jpg

More pics of the OEM platform

https://lh4.googleusercontent.com/-6...812_115908.jpg

https://lh6.googleusercontent.com/-x...812_120122.jpg

https://lh4.googleusercontent.com/-p...812_120134.jpg

https://lh4.googleusercontent.com/-V...812_115938.jpg

Oh, and this pic shows where the water line was and how the platform was cutting into our surf wave.

https://lh5.googleusercontent.com/-L...s800/photo.jpg

I have a video that shows the platform. I had to upload it to youtube because the site I had it on before isn't working. The link will be:
http://youtu.be/36X8WtKvCm8

Build Pics

http://i109.photobucket.com/albums/n...pseb2d425f.jpg

http://i109.photobucket.com/albums/n...ps649d50bb.jpg

http://i109.photobucket.com/albums/n...psba7d3d28.jpg

http://i109.photobucket.com/albums/n...psada2a430.jpg

Comparison Pics

http://i109.photobucket.com/albums/n...ps7f7e41dc.jpg

http://i109.photobucket.com/albums/n...psa1a9492d.jpg

Installed last night for prototype testing today

http://i109.photobucket.com/albums/n...ps8dc9ec84.jpg

http://i109.photobucket.com/albums/n...ps42cff8d4.jpg

http://i109.photobucket.com/albums/n...ps7ce8d6b5.jpg

Just for the record, yes we know it is OSB, not traditional plywood, and yes we know that the dual 7/16" layers will separate over time, and yes we know that just the undercoating will not prevent this or 100% stop the moisture.
This is just to test and finish the season out to see if we should pursue a more expensive single sheet marine plywood fiberglassed version with pad and probably grab rails.
If we do make that, we figure we will have materials enough to make two, so one will most likely end up for sale on here for anyone who likes the idea and wants one too without the labor.
I am currently waiting at the boat ramp for Trayson to get here to test this sumbyatch out and here he is posting a build thread lol.
Will post pics of the results of todays testing soon... If he gets here before dark. ;)

Test was successful. Only the tip of the corner was in the water and there was little to NO interference with the surf wave. The brackets being a little in the water is unavoidable and any turbulance from that seems to be going straight into the prop wash.

Bottom line is that the new platform did NOT interfere with the surf wave and we felt like we had an increase in push and maybe even a little more pocket. I forgot my waterproof cam, so I couldn't post any vid looking at the boat from the surfer's point of view. But we got as good of pics as we could from the back of the boat.

As soon as Desi gets them uploaded, we'll share them here.

At rest in semi rough water:
https://lh6.googleusercontent.com/-I...926_180947.jpg

So tonight we ran the same weighting we did with the exception of moving the 150 from the rear center seat to on top of the tube sack in front of the 750. Basically moving one person to the observer seat instead of the doghouse. This balanced out us having someone in the rear seat for pictures and rope duty instead of having the bag and a person behind the doghouse, so pretty much the same type of setup we have run before.

I could definitely tell the difference in how long the pocket was and how much push the wave had. This was definitely due to the fact that the new platform sits different.
The new platform sits the same vertical height as the old platform, however it is technically higher because it is a solid, smooth bottom platform that is only on the brackets, whereas the OEM platform sits on the brackets and has a lip around it that extends about 2" from the top of the platform. So in essence, this design "raised" the platform 2" out of the water all across the board.
It also is about a foot shorter over all from side to side, so the sides do not dig into the wake and act as trim tabs. In fact, even though Trayson said the tip of the platform touched the water, in the video I am posting and in the pics you can see that none of the platform touches the water at all while at surf speed. It is truly an "unaffected ride" platform, no trademark infringement implied, it just literally doesn't affect the ride.

I have surfed this boat all summer and can easily say that this was the best wave it has ever put out. The pocket was longer and it had more push. Normally, being a bigger guy I had struggled to stay in the pocket and typically had to be really forward on the board. Tonight I had no problem staying in the pocket, my foot positioning was normal and I had to actually put on the brakes quite a bit to keep off the platform I had so much push I haven't experienced on this boat before. I had plenty of pocket to play around in and do some carving up and down the wake. I was able to do a few floaters to the back of the wave, drop down to the flats and just let the wave push me back to the front of the pocket. Something I have previously had a very difficult time doing.

The only other boat I have surfed is a 2012 Wakesetter VLX loaded up with at least twice the ballast as the Supra. While this wake did not have as much push as that, it was comparable. If I had to compare the two, I'd have to guestimate the Supra had about 75% as much push. I was able to ride the same way and play around on the Supra as I do on the wakesetter. This was a welcome surprise, considering normally I had to fight to stay in the pocket to even freeride the Supra.

With this good experience today, we are ruling it as a great success. We will definitely be moving forward with making the final version in the off season.
The only thing we noticed that might be negative is that with the "raised' platform, and it being flat, without a lip, there was more noticable exhaust coming from under the platform. Normally it would get caught in the lip and slowly escape when it built up or escape all at once when you turned the right way or stopped. A FAE build will definitely be in the future as well.

Enough talk, here are some pics, and some videos.

Rear/Side View:
http://i109.photobucket.com/albums/n...psf6a11a4d.jpg Looks pretty stealth
Side View:
http://i109.photobucket.com/albums/n...ps0d16ac38.jpg
At speed, notice no contact with the water:
http://i109.photobucket.com/albums/n...ps62a47a4d.jpg
The edge and corner, also not contacting the water:
http://i109.photobucket.com/albums/n...psfe927201.jpg

The wave without the 150 filled (1300 lbs of ballast), notice the visible exhaust:
http://i109.photobucket.com/albums/n...ps2d252923.jpg
Platform at rest weighted:
http://i109.photobucket.com/albums/n...ps40231d08.jpg
The wave with the 150 filled, not a big change between 1300 and 1450lbs of ballast:
http://i109.photobucket.com/albums/n...ps8d51f141.jpg

Video of the platform at surf speed 1300lbs of ballast:
http://i109.photobucket.com/albums/n...ps892bea32.jpg
Video of wave at surf speed 1300lbs of ballast:
http://i109.photobucket.com/albums/n...ps14238f81.jpg
Video of Platform and wave at surf speed 1450lbs of ballast, this is what we rode on:
http://i109.photobucket.com/albums/n...psd662e4e4.jpg

I don't think we got any video of us riding the wave as our photographer friend was taking stills with his SLR. We will get some of those posted up as well when he gets them uploaded.

Anyway, that's the results of our prototype build. Feel free to ask any questions. Requests for more pics or videos shouldn't be a problem either because I'm sure we will want to get out and ride this more this year.

Dibs! Unless shipping is more expensive than what I can make myself!

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Originally Posted by kvand347

Dibs! Unless shipping is more expensive than what I can make myself!

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Of course, who knows what Desi would price he handiwork at!!! *evil laugh*

But, when that time comes I can get shipping quotes. My work has a great contract with fedex ground. I remember I was able to ship my boat transmission from WA to OH for $25 + insurance, and it was like 55 pounds.

Sweet! I could probably just cut up my supra pad and attach it on top of the new platform. That would save me some cost!

I think this video is decent aside from the pixelization to show the surf wave and that the platform was basically not affecting the wave at all and you can see we're running water to the rub rail (and it was kinda rougher).
http://s109.photobucket.com/user/pha...2e4e4.mp4.html

This one does a good job at showing the platform itself in action:
http://s109.photobucket.com/user/pha...bea32.mp4.html


And I think that the platform even as a prototype looks pretty decent on the boat:
http://i109.photobucket.com/albums/n...ps4db6f12a.jpg

http://i109.photobucket.com/albums/n...ps59df0102.jpg

http://i109.photobucket.com/albums/n...psf6a11a4d.jpg

Ideally I'd price it for the cost of the materials just to offset the cost of our platform. Cost of materials for the new final platform are estimated as follows:
3/4" severe weather plywood $55
Fiberglass mat $20
Fiberglass cloth $20
Fiberglass resin $100
Hydroturf covering $80
Misc materials, brushes, rollers, sandpaper, adhesive, etc $25
Gel coat if a different color is desired (we can also tint the resin, probably gonna do black for ours) $50
So all in all, expect a cost of about $300-350 plus shipping. Basically coming out to, we break even on the materials and build one for free labor and have one for ourselves.

Btw: with the thickness of the platform, you're able to use all your factory hardware. The platform will be predrilled if you are using it on a supra with the same oem platform brackets. Otherwise it will be blank.

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Originally Posted by phathom

Just for the record, yes we know it is OSP, not traditional plywood, and yes we know that the dual 7/16" layers will separate over time, and yes we know that just the undercoating will not prevent this or 100% stop the moisture.
This is just to test and finish the season out to see if we should pursue a more expensive single sheet marine plywood fiberglassed version with pad and probably grab rails.
If we do make that, we figure we will have materials enough to make two, so one will most likely end up for sale on here for anyone who likes the idea and wants one too without the labor.
I am currently waiting at the boat ramp for Trayson to get here to test this sumbyatch out and here he is posting a build thread lol.
Will post pics of the results of todays testing soon... If he gets here before dark. ;)

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Just for the record it's OSB oriented strand board Phathom.
Out of curiosity, why not build it out of 1 inch plastic? Seems easy enough and you know it won't rot.
1 more thing....i love it

Thanks Phathom! Definitely less than an OEM from Supra, but more than I thought it would cost.

2500--where would you source 1" plastic?

interstate plastics
http://www.interstateplastics.com/?u...k%20plexiglass

Holy crap spendy!!!!!

http://img.tapatalk.com/d/13/09/28/batymu6u.jpg

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Originally Posted by villain

Holy crap spendy!!!!!

http://img.tapatalk.com/d/13/09/28/batymu6u.jpg

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Wow, my all composite boat must be worth a fortune in materials!!!!!!!!!!!!!!!!!!!

Attachment 13262
you picked an expensive one

How will hdpe hold up to the sun and heat when out of the water?

i believe i found this in the marine section, but i honestly have no idea.

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Originally Posted by 2500HD

Just for the record it's OSB oriented strand board Phathom.
Out of curiosity, why not build it out of 1 inch plastic? Seems easy enough and you know it won't rot.
1 more thing....i love it

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Thanks, I've been calling it OSP Oriented Strand Plywood, which is what it is labeled for sale at our local home depot. But yes, you are right, OSB. Also the pricing I put up was the material cost for both platforms (ours and the extra) Also the color and mat are optional. The cost without mat or color is about $250 to build two 3/4" fiberglass surf platforms in the same type of way the prototype sits now.

Not bad of a price for the material of some HDPE. Might be something to consider, however as I said, for that cost we can do 2 platforms with pads which we'd still need for the HDPE one. However saving a day or two of labor has it's own merits considering I'd only have to make 3 cuts total and round the edges off before adhering a pad. The entire thing could be made and ready to be on the water the day after the materials got delivered.
Attachment 13275

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Originally Posted by villain

How will hdpe hold up to the sun and heat when out of the water?

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HDPE is the material they use to make snowboard park features -- I suspect it would hold up just fine!

Ok kewl!! You learn something new every day

The downside to hdpe I believe is that it shrinks quite a bit. In the size of a swim platform, probably doesn't matter though.

Guessing it would also sag more than the standard alternatives.

How's the progress coming?

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Originally Posted by 2500HD

How's the progress coming?

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I have taken the boat out once since the prototype run. We loaded it up with almost a ton of ballast and the new platform worked fine. It's most certainly destined to ONLY be a prototype, as the spray on bedliner is already starting to flake off just from expansion/contraction of being outside in my RV parking.

We might go out tonight with it. Use it until it falls apart I guess! ROFL. We'll be making something more substantial over the winter. The proof of concept is sound, and no reason to adopt any other design.

I did call up TAP Plastics in Portland and they can source me a 62x24" piece of 3/4" HPDE for $188. So, the quickest and easiest would be to grab that, cut off the corners to make my trapazoid shape, round off the edges, and throw some closed cell foam on it for padding and be done.

My buddy kinda wants to go the plywood/fiberflass route because he could make a couple for the price of the 1 HPDE. We'll see what happens though. If we go out tonight, I can try to get some better video.

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Originally Posted by trayson

If we go out tonight, I can try to get some better video.

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Looks like the Supra is parked for the night. Got an invite to ride a Tige V-drive. I'll be cheating on my DD...

Tige huh?? Good choice! Lol. Which one is it?

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Originally Posted by villain

Tige huh?? Good choice! Lol. Which one is it?

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Pre2200.

We had it with a tube sack under the surf side seat and 400 in the locker witH 2 people in the bow surfside and 3 people surfside. It was great.

Update. After a lot of research I've found that pretty much no adhestives are going to stick to the HPDE that I was planning on using for a future platform. I had planned to put foam on top of the platform. However, I have found that they make textured anti-slip versions of both Starboard and Seaboard. The best price and local availability for me will be the Seaboard Grip-X product. However, I have to buy a whole sheet, which is enough to make two platforms. I think I'm going to wait until I have someone else that wants one to distribute the cost of materials better.

I think I might just throw some some adhesive and some foam on my prototype platform and just use that until it starts to fall apart. LOL.

You will have to use bolts instead of screws with hdpe matl that was my experience screws pulled out easy

I'm in. Just a thought would line x stick to it?

Screws work fine, you just need to pre drill. I would recommend using thinner material and bracing to cut down on weight and cost. Going from 1"to 3/4 is a huge savings

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Originally Posted by trayson

Update. However, I have to buy a whole sheet, which is enough to make two platforms. I think I'm going to wait until I have someone else that wants one to distribute the cost of materials better.

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I am in. 10char

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Originally Posted by beat taco

I'm in. Just a thought would line x stick to it?

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I kinda doubt it. From what I've been told by the plastics people there's not much that will adhere to it. That's why I've decided that the best bet would be using the Seaboard Grip-X, which has the texturing already on it.

Quote:

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Originally Posted by beat taco

I am in.

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Would you be down to do a white platform? I can get the white for less money than the black. A sheet of black is about $40 more than white. So if you wanted black, we could certainly do that too. It'd just add a little cost.

I was going to postpone my final platform build, but if you want one, I could probably make it happen sooner. :-) What kind of timeline were you thinking?

These were the dimensions of my prototype. If I was going to make you one, I'd need to know the size of your platform brackets to make sure I got the length and width optimized for yours...

https://lh3.googleusercontent.com/-L...Dimensions.jpg