Designing surf tabs out of auto trim tabs

[wolff supra21v]

Here is what I was thinking, please any input on this would be great.
I am trying to make a shopping list for black Friday/ cyber Monday.

Here is my shopping list right now.

(2) Lenco Trim tab Edge mounted 9"Wx12"L Part # 20159-001 Cost $94 each
(2) Lenco Actuator 4-1/4 stroke Part # 15059-001 Cost $210 each
(2) Lenco upper actuator mount Part #15070-001 Cost #18 each
(2) Lenco Lower actuator mount Part # 50015-001d Cost $16 each
(2) Lenco 20' wiring harness Part # 30133-103D Cost $33 each
(1) Lenco Switch Led indicator kit Part #15070-001 Cost $320
(This switch kit has the wrong part number this one is for a 2-1/4 stroke actuator I need the one for a 4-1/4 stroke actuator but the said it is the same cost) (I am trying to get a part number for it now but it may be a special order the local lenco dealer.)

If I ordered today I would be looking at $1062 plus any taxes or shipping if required.


Okay now here is my plan

Install the two trim tabs Like they are designed for but use a longer stroke actuator to use them as Surf tabs.

I was looking at a kit with the standard 2-1/4" stroke actuators but the plates will only go down to about 22 degrees.
with the 4-1/4 stroke actuators it will go down to about 60 degrees. this was verified with cardboard and a tape measure this weekend.

I think I will be good on the controller it has an input on it. So if it does not have 12 volts on it, it automatic raises the plates to the all up position. (I was going to put this in a rocker switch to turn the system off and on with.) It also has led indicators to tell you were the tab is.

This weekend I winterized my boat and a cut out a piece of cardboard for the tabs.
Here is what I came up with.

1. The back of the supra 21v has a 1/2 in surface change where I want to put the tab.
My plan is to use a piece of Trex decking I have left over to shim this level.

2. The lip of the platform will be in the way. and it is going to be tight against the platform.
It should not be a problem cutting 2 or 3 inches of the lower lip off the platform(It is the part that is against the back of the boat no one should be able to see this.). I might have to raise the platform a inch or two.

[trayson]

I'll be following your progress, that's for sure. :-)

[wolff supra21v]

Broke down and order all the parts for the trim tab system. I was hoping to save some money but all I save was shipping taxes and just a little more than that.
everything should be in 5 to 7 days. but I still have 3 plus months to get in on the boat for testing.

[wolff supra21v]

Everything but the controller has came in for the system. it is suppose to ship on the 28th I am hoping to move the boat from storage to the work shop Friday or Saturday this week. to start the install.

I also have a second guy looking at redoing the vinyl today.

[viking]

Looking forward to seeing this all come together. Pics pics pics along the way!

[ISUclonesrule]

Any further work/design done on the trim tab surf system? I know it's winter and you are probably not in a big hurry but this seems like a great project! Thanks for posting!

[MoombaPat]

Any head way on your design? Curious to see how it turns out!

[wolff supra21v]

My construction business got in the why the last two weeks had a friends house catch on fire and a New years day mishap with a side x side going through a garage wall at my parents house kept me from working on the boat. no one got hurt just kept me from working on the boat.
I am hoping to start something in the next week. being in Illinois it will be rough to test anything till spring time.

[jasonwm]

We've been exploring these options hard for close to two years. I think you'll have a very difficult time getting the results you're looking for with standard a standard trim tab; they additional surface area alone just isn't enough to do the job. Look at the Mastercraft Gen I Surf Tabs for an example of this.

I'll be watching to see what your results are though, as we haven't tested them on any Moomba hulls.

[wolff supra21v]

I got the boat into my heated shop this weekend.
Got all the parts I need to put the system together.
The one think I was afraid of with the longer stroke actuators the are physical a little to long to fit under the swim platform.
I was already planning on raising my platform up an 1".
So I am going to raise it an inch and I was already planning on using the tab as a baseplate to add different shape plates to. so now I just got to add about 3" of length to the trim tabs so the actuator will mount a little further back on the tab. (we are going to bolt the things together for now to we see how the system works in the water than when we have it the way we want it we will weld it than.)

On thing nice my family owns a scrap yard so we get all kinds of scrap metal in (stainless and aluminum)
also I have a brother that is a boilermaker and is awesome at welding. He has everything for welding stainless and aluminum. To top that off he is on my boat most the summer and loves to surfing.

We are going to play with it tonight so I will try to postsome pics tomorrow.

[Boonejeepin]

Looking forward to seeing your progress.

[DOCDRS]

So for a quick reference, are all these different surf tabs, actuators , plates,gates and flow systems are all deployed on the side you are not surfing on? Or are some deployed on the surf side ? Not to hijack the thread

[jasonwm]

I got the boat into my heated shop this weekend.
Got all the parts I need to put the system together.
The one think I was afraid of with the longer stroke actuators the are physical a little to long to fit under the swim platform.
I was already planning on raising my platform up an 1".
So I am going to raise it an inch and I was already planning on using the tab as a baseplate to add different shape plates to. so now I just got to add about 3" of length to the trim tabs so the actuator will mount a little further back on the tab. (we are going to bolt the things together for now to we see how the system works in the water than when we have it the way we want it we will weld it than.)

On thing nice my family owns a scrap yard so we get all kinds of scrap metal in (stainless and aluminum)
also I have a brother that is a boilermaker and is awesome at welding. He has everything for welding stainless and aluminum. To top that off he is on my boat most the summer and loves to surfing.

We are going to play with it tonight so I will try to postsome pics tomorrow.

Awesome, like I said I can't wait to see what your results are.


So for a quick reference, are all these different surf tabs, actuators , plates,gates and flow systems are all deployed on the side you are not surfing on? Or are some deployed on the surf side ? Not to hijack the thread

They are essentially all deployed on the non-surf side of the boat, regardless of the actual implementation.

[trayson]

So for a quick reference, are all these different surf tabs, actuators , plates,gates and flow systems are all deployed on the side you are not surfing on? Or are some deployed on the surf side ? Not to hijack the thread

Explained pretty well in this thread:

https://forum.moomba.com/showthread.php?25041-The-basics-of-Surf-Systems-(and-platform-modifications)&highlight=surf+systems

[wolff supra21v]

Just a little update.
I been taking all my seats out right now for new vinyl so that slowed this down a little bit.

We done some measuring. and trying to get a little extra material right now. I am getting some 1" square tubing to raise the swim deck up a little.
also I am going to cut two 6"x6" stainless plates this weekend to add to the length of the trim tab. I order 9" wide by 12" long tabs. but by ordering the longer actuators to get the tabs in an up position that should not affect the wakeboard wake. I need an addition 2-1/2" to the length of the tab.

Also I got two piece of composite decking left over from my house. I am going to cut and trim them to give a good flat area to mount the trim tab to.

[kaneboats]

Please take some pics of the process and share with us. Can't wait to see how this comes out for you.

[moombadaze]

would love to see some progress, even a mock up would be nice

[wolff supra21v]

Due to the sixty degree weather in IL this weekend I did not work on the boat that much.
Here are some pics and what I am thinking.
I connected actuator with the tabs and electrical switch system a screwed the tab to a post and here what I came up with I actual only have about 30 degrees of movement I was hoping for more around 50 degrees of movement. Here are some pics of the tabs mounted to the post 1st two with the tab all the way up and second two with the tab all the way down.

21341213422134321344

[wolff supra21v]

Also here is a picture of the switch. this system seam like it will work nice. It has a key/throttle power option. (there is an extra wire and when it loses power it automatically puts the tabs in the up position.) I plan on putting this on a rocker switch and labeling it surf tabs only, it needs to be on when using the tabs. It would be nice if it remembered where it was when power back up so you would not have to reset everything but there is also 10 leds showing the location of either tab.

Also I am wanting to mount the actuators in the dark gray strip next to the swim platform mount and by looking at this with the platform back on I really do not need to raise the platform if I trim about 2" of the outer lip off of the platform next to the mounting bracket.

[trayson]

Due to the sixty degree weather in IL this weekend I did not work on the boat that much.
Here are some pics and what I am thinking.
I connected actuator with the tabs and electrical switch system a screwed the tab to a post and here what I came up with I actual only have about 30 degrees of movement I was hoping for more around 50 degrees of movement. Here are some pics of the tabs mounted to the post 1st two with the tab all the way up and second two with the tab all the way down.

21341213422134321344

Easy. Mount the actuator more towards the middle of the tab vs all the way at the far back end. That's what Moomba is doing with the autoflow.

Look at this pic of the autoflow. Moomba is getting their desired range of motion out of only 1 inch of throw on the shorter throw actuators...
https://lh5.googleusercontent.com/-QAF3MLFwPnQ/VLAVjRtzdTI/AAAAAAAAXSU/D3J3B-HEeEQ/s800/20150108_182909.jpg

[trayson]

Oh, now I see the problem. You'd have to mount the actuators HIGHER to take advantage of the increased range of motion. So maybe that's not an option??

On my XLV with my custom platform mounting the actuators outboard of the platform is what I'd be planning on if/when I do a mod like this.

https://lh6.googleusercontent.com/-eQA4gdfebvw/VE8KH-BnaQI/AAAAAAAAUvc/j9vbf8ybNac/s640/20141027_201307.jpg

[trayson]

Also here is a picture of the switch. this system seam like it will work nice. It has a key/throttle power option. (there is an extra wire and when it loses power it automatically puts the tabs in the up position.) I plan on putting this on a rocker switch and labeling it surf tabs only, it needs to be on when using the tabs. It would be nice if it remembered where it was when power back up so you would not have to reset everything but there is also 10 leds showing the location of either tab.

Also I am wanting to mount the actuators in the dark gray strip next to the swim platform mount and by looking at this with the platform back on I really do not need to raise the platform if I trim about 2" of the outer lip off of the platform next to the mounting bracket.

I like your idea of a rocker switch that's required to power "on" the surf tabs. My biggest concern/fear would be that I would try to pull onto the trailer with the tabs down! The key off wouldn't help in this scenario because I still have the boat running when I'm loading onto the trailer and hitching up the bow strap. And there's just enough overlap between the back of the hull and how far the outboard bunks stick out in the rear that I'd worry about banging the tabs on the bunks...

You can see on this pic how my bunks stick out just a little farther than my hull on the outer bunks.
https://lh5.googleusercontent.com/-2jTCBMQ_o80/VNJzeINSjBI/AAAAAAAAXoI/9aejEl455v0/s800/20150203_134551.jpg

This pic shows it really well.
https://lh5.googleusercontent.com/-7ZrwKXOLzfQ/VNJzqVyhnjI/AAAAAAAAXoY/IxXAwV08ABA/s800/20150203_134616.jpg

Certainly it'd be possible to trim down the bunks to ensure that couldn't happen. But that's a bridge I'd cross when I did tabs.

Well done! Keep blazing the trail. Looking forward to more updates.

[jasonwm]

I think you'll find that's WAY too much deployment. In all of our testing, anything over 11-12 degrees off the running surface has a negative impact on the wake. This will certainly depend somewhat on the design of the tab, but the amount of deployment you've got right now is A LOT.

Trayson, you'll definitely want to cut those bunks down once you get ready to tackle this.

[wolff supra21v]

I hope that is two much deployment, I would just hate to need just a little more that I did not have.
I do not remember how far down the mastercrafts tabs deploy but I was thinking I seen the surpa's tabs deployed down around 80 degrees.

Trayson, my bunks are the same way and that is the plan also to cut about 3 to 4" off them.

[jasonwm]

You can always put a block between the upper mount and the transom to act as space if you need more angle, but I don't think that will be an issue.

[Boonejeepin]

Jason - Is there an ineffective middle ground on angle? Seems like the Swell, Autoflow, and Centurion quick surf all go way beyond 12 degrees.

[trayson]

Jason - Is there an ineffective middle ground on angle? Seems like the Swell, Autoflow, and Centurion quick surf all go way beyond 12 degrees.

Centurion for comparison:
https://lh5.googleusercontent.com/-mpzzULiYe1k/VLAVsziB-8I/AAAAAAAAXTM/jV3bwgi23OA/s800/20150108_203616.jpg

I don't have a good pic of the autoflow deployed, but a pic where you can get kind of an idea relative to the wakeplate:
https://lh5.googleusercontent.com/-QAF3MLFwPnQ/VLAVjRtzdTI/AAAAAAAAXSU/D3J3B-HEeEQ/s800/20150108_182909.jpg

[Boonejeepin]

After seeing those pics I think I had an incorrect concept of how far the Autoflow and Centurion quick surf extends downward.

[trayson]

After seeing those pics I think I had an incorrect concept of how far the Autoflow and Centurion quick surf extends downward.

Supra Swell. this gives a better idea of angle since the mount has a "flat" part for reference.
http://www.wakemakers.com/wp/wp-content/uploads/2013/11/supra-swell-blade.jpeg

[Boonejeepin]

I thought it went further down.

[wolfeman131]

I thought it went further down.

you are correct

watch the video at :38 and 1:33

http://vimeo.com/79996153

[Boonejeepin]

Interesting new product from Wake Worx. Their tabs are well beyond 12 degrees as well. Still interested in Jason's input on angles. http://tapatalk.imageshack.com/v2/15/02/11/8333c34f081987638bab9df1d2c294ab.jpghttp://tapatalk.imageshack.com/v2/15/02/11/f042c01f04661535a8e0b3f01e5cbdd1.jpg

[jstenger]

Interesting new product from Wake Worx. Their tabs are well beyond 12 degrees as well. Still interested in Jason's input on angles. http://tapatalk.imageshack.com/v2/15/02/11/8333c34f081987638bab9df1d2c294ab.jpghttp://tapatalk.imageshack.com/v2/15/02/11/f042c01f04661535a8e0b3f01e5cbdd1.jpg
Looked on there website, but couldn't find any info on these tabs yet.

[Boonejeepin]

Looked on there website, but couldn't find any info on these tabs yet.

The only info I have seen is on FB.

[trayson]

you are correct

watch the video at :38 and 1:33

http://vimeo.com/79996153

Damn you're right. that looks damn near 90 degrees.

That is what I remember hearing about the swell. That certainly makes sense with all the Swell's robust bracing.

https://lh5.googleusercontent.com/-3-riImgwvzU/VNubSjGjE8I/AAAAAAAAX4c/jWJSneNrOMs/s800/Swell.jpg

[bergermaister]

Is that the control switch centered on the transom on the Wake Worx setup???

[trayson]

Is that the control switch centered on the transom on the Wake Worx setup???

That's a fake transom, and the switch is obviously there just for display. Kind of like how the Moomba with autoflow at the pdx boat show had a switch hanging off the back of the transom.

Obviously that switch would be mounted near the driver.

[mmandley]

Damn you're right. that looks damn near 90 degrees.

That is what I remember hearing about the swell. That certainly makes sense with all the Swell's robust bracing.

https://lh5.googleusercontent.com/-3-riImgwvzU/VNubSjGjE8I/AAAAAAAAX4c/jWJSneNrOMs/s800/Swell.jpg

This is exactly what I was referring to back when I mentioned how disappointed I was that the Auto Flow doesn't go down as fare as the Swell. I was really hopping for a Swell system basically. I still don't get how the Auto Flow, and all these new systems out are really changing the wave. I don't see any of them as changing the convergence of water coming from under the boat.

I see them as a plate that is pressing into the water exiting the hull and helping to Delay the time at which it forms the wave. This to me is not really changing the wave. It also seem the tab systems are only going to roll the boat over more as they are deployed.

This whole thing is whats keeping me from pulling the trigger on an upgrade. I really need to see, surf these systems to see if they are worth the money the suppliers are asking for them.

[trayson]

Makes sense Mike. I guess we'll let Wolf and Boonejeepin blaze the trail and find out what works and what doesn't...

I blazed the trail on my Supra when I did an NSS style system. I'm holding off for a little bit on the XLV...

[jstenger]

I was hoping that they would just add actuators to the current Flow which would look similar to the pic below.

http://i1217.photobucket.com/albums/dd382/Joestenger/tapatalk_1399471940703_1.jpeg (http://s1217.photobucket.com/user/Joestenger/media/tapatalk_1399471940703_1.jpeg.html)

I don't think it would be that hard to do.

[trayson]

I was hoping that they would just add actuators to the current Flow which would look similar to the pic below.

http://i1217.photobucket.com/albums/dd382/Joestenger/tapatalk_1399471940703_1.jpeg (http://s1217.photobucket.com/user/Joestenger/media/tapatalk_1399471940703_1.jpeg.html)

I don't think it would be that hard to do.

But would it really be worth $500+ in actuators plus the switches and wiring just so you don't have to stick your hand in the water to switch sides?



It's not like any of these systems using the long throw 102 actuators are going to be fast enough to do transfer tricks. I've ridden a surfgated boat with the 102 actuators and the gates don't switch fast enough. That's why malibu had lenco make them special actuators that are the 102 "fast". And you can't get them unless yourre a malibu dealer with an RMA on a bad fast actuator. *maybe* you could get the Supra version of the heavy duty fast actuator, but who knows.

It's possible the autoflow would have a fast enough throw for transfer tricks because they use the short throw actuators and only have 1" of travel on the actuator to fully deployed...

[viking]

If your going to build a system do it right and do an NSS type like this guy:
http://www.wakeworld.com/forum/showthread.php?t=800079&highlight=surf+system

Best DIY System I've seen to date!!

[bergermaister]

Right.... Look how nice and square his back corners are transitioning from bottom to transom. No step.

Badazz work though.

[jasonwm]

I can't comment on the design specs of other systems, except to say there are two schools of thought here; either create lift to list the boat, or create drag to force the boat to crab. SurfGate falls in the former category, NSS and other systems, like Swell, land in the latter.

Testing on our product (which is decidedly different from anything else that has been posted thus far) has shown that unless you're going with the drag model, deploying the tab any further than 10-12 degrees just makes it act like a brake, and eliminates the lift that is needed to list the boat at speed.

Obviously this is all dependent upon the design specs and engineering for the system and what it is trying to do. But for anyone thinking they'll just bolt some trim tabs onto the transom of their boat, I think it would be a mistake to have them deploy very far. Obviously this needs to be modeled and tested in detail, and I could absolutely be wrong, but I feel pretty confident in the results.

[trayson]

I can't comment on the design specs of other systems, except to say there are two schools of thought here; either create lift to list the boat, or create drag to force the boat to crab. SurfGate falls in the former category, NSS and other systems, like Swell, land in the latter.

Testing on our product (which is decidedly different from anything else that has been posted thus far) has shown that unless you're going with the drag model, deploying the tab any further than 10-12 degrees just makes it act like a brake, and eliminates the lift that is needed to list the boat at speed.

Obviously this is all dependent upon the design specs and engineering for the system and what it is trying to do. But for anyone thinking they'll just bolt some trim tabs onto the transom of their boat, I think it would be a mistake to have them deploy very far. Obviously this needs to be modeled and tested in detail, and I could absolutely be wrong, but I feel pretty confident in the results.

While I appreciate your explanation, I can't say that I agree completely with it. You're saying that the goals of a surf system are to list or crab. I don't really agree. The goal of a surf system is to delay the convergence of the wakes.

There are members here that have made "ghetto gates" that don't have an angle at all and essentially extend the running surface of that side of the hull, but in a straight line, not in the Malibu 22 degrees. I guess it could be argued that even with a straight ghetto gate that it's effectively making the boat crab because you're kind of placing a straight rudder on the non-surfside corner. But then we're talking semantics.



I guess the only thing that I really disagree with you on is that NSS is in a fundamentally different school of thought from the surfgate. they're not. And that's why Nautique LOST the lawsuit and is paying millions to Malibu.

I retrofitted my own manual version of an NSS onto my supra. Mine was modeled after the Nautique's in that it extended 3" OUT from the hull and only .75 to 1" DOWN. My boat sat level, just like the G23's do when they're deploying their NSS. (I've ridden a G23 and a G25 with NSS.) Likewise, my NSS most certainly affected the turning of my boat. we got used to only turning away from the surf side when it was time to come back and pick up our rider. :-)

The NSS is most certainly affecting the side of the hull, just like the Surfgate. however, there's an inverse relationship between length of the delayed convergence device and the length necessary for it to be effective. My NSS stuck up 90 degrees from the hull. At full deployment it only needed to be 3". The surfgate is 17.5" and is at a 22 degree angle. The members that have made 0 degree ghetto gates have found that they needed to be even longer than a surfgate because they had no angle of deployment.

I would imagine that my principle holds true on downward deployed devices, that the length and surface area are inversely related to the angle of deployment...

This seems to hold true in the marketplace.
Surfgate = BIG with a moderate angle
Moomba Flow = smaller with a 90 degree angle
Centurion quicksurf = big surface area with a more moderate angle
NSS = small with a 90 degree angle
Mastercraft Gen 2 = more moderate angles with big surface area
MB Sports Gen 2 = 90 degree angle with a smaller surface area beyond the hull (basically an NSS with a different method of deployment)

The Supra Swell seems to be the one that I can't quite nail down as far as the angle vs. surface area. Because it's certainly a reasonable amount of surface area, but they crank that thing all the way down as well. Yeah, it's likely acting like a brake in addition to delaying the convergence? And maybe that's having it function like a surf system and a "wedge" type device at the same time?? Not sure. Sadly it's one of the systems I didn't get to ride last year. I will try to get on one in May.

I'm by no means an expert. But I do have first hand experience with a handful of surf systems...

[cornrickey]

Agree, maybe we're getting hung up on terms but my gates are held out by a surprisingly small hinge pin. There is no way it is causing the boat to yaw (crab). Even @ speed.

[wolff supra21v]

Tomorrow I am picking up some aluminum blocks to make a level spot on the back of the boat. to mount the tabs to.

I think the biggest thing I am trying to get away from by adding the tabs is with my 21v I have 750lb sacs in the back compartments and I have to put a 400lb sack on the back deck. also if I have less than 4 people in the boat we put a 400lb sack on the back seat. I am having my seats re-vinyl right now and I hate putting sacs on top of the vinyl I put towels down but just do not want the extra ware and tare on the seats.

[jstenger]

Tomorrow I am picking up some aluminum blocks to make a level spot on the back of the boat. to mount the tabs to.

I think the biggest thing I am trying to get away from by adding the tabs is with my 21v I have 750lb sacs in the back compartments and I have to put a 400lb sack on the back deck. also if I have less than 4 people in the boat we put a 400lb sack on the back seat. I am having my seats re-vinyl right now and I hate putting sacs on top of the vinyl I put towels down but just do not want the extra ware and tare on the seats.
Just have the guys put some heavy steel plates in the seats before the new vinyl goes on. It could be your secret ballast. :D

[wolff supra21v]

I am already running steel tractor weights in the boat. Boat and trailer weight 5800lb on 6000lb trailer I do not think I can add any more.

[Boonejeepin]

I am already running steel tractor weights in the boat. Boat and trailer weight 5800lb on 6000lb trailer I do not think I can add any more.

Glad to see that I am not the only crazy one.😄

[wolff supra21v]

So I got at little time to work on the boat.

I got the aluminum blocks made and ready to be installed on the boat.

I also drilled the dash and mocked up the control switch.

Next time I work on the boat I get to do the fun part start drilling and putting screws into the hull of the boat. the first hole always a little nerve racking but it all down hill after that.
The electrical is all figured out should take me about a hour to install and finalize.

here is a few pics.

Also on a positive note the interior is suppose to be done next week.

21447214482144921450

[wolff supra21v]

few more pics

[Rakkasan187]

Awesome work! Have any of you guys taken a look at the Gosurfassist system. I am going to have them install there kit on my 2006 21v here in the next month or two. There system is pretty cool and allows you to do wake to wake transfers. seems like they have done a lot of R&D on there tabs.

[wolff supra21v]

I have look at them a little but I already had all my parts bought before I found out about them. One thing I was looking at is putting some fins on the bottom of my tabs to help direct water like what they have.

We are going to the St. Louis Mo boat show tonight I plan on looking at all the different tabs I can to see if the is something I need to incorporate into mine.

I have the tabs mounted on the boat but have not mounted the actuator yet. We were waiting till after tonight. Want to look other setup over to see if I am missing anything.

[Rakkasan187]

Ill be looking forward to see how yours do. The biggest pro I see to running these surf tabs is being able to run the boat weight evenly. I hate having to tell people to all sit on one side and don't breath..LOL. I hoping that with the addition of the GoSurfAssist and a new Supra swim deck it will clean up the wave. We will see.

[wolff supra21v]

I got the tabs all installed now only thing left is to pull it back off and caulk/glue everything and reinstall everything.
All the wiring is ran and the controller has a home. but I need to install the interior before I mount it in its final resting place.

I currently have aluminum plates add to the trim tabs that will be replace with stainless but we first want to water test. I would like to put some fins on the bottom of the stainless plates but want to test everything with aluminum (I have a bunch of pieces of aluminum to play with but no stainless on hand)

I had a crack in my wakeboard tower and figure since the interior was out of the boat best time to weld. We welded it last night.

My plan now is to detail the boat this weekend (brother-in-law has his old buffer plus a new one he want to try out)
than we install the interior vinyl.
My goal is to do the water test on the weekend of 4/4 but as the Illinois weather goes it could be 30 degrees or 80 degrees we will have to wait and see.

[wolff supra21v]

Here are a few more pics

2155321554

[2500HD]

If i could make a suggestion it would be to move the plate that you have added to the tab to the top. If water gets between the two it could possibly bend it.

[trayson]

I can see that you added increased length to your tabs. I'd suggest playing with different shapes that utilize more width. Try some shapes that have been used by other manufacturers, like the shape of the autoflow or the shape of the Centurion Quicksurf.

[wolff supra21v]

Well got the boat out this weekend finally. the bad did not get any pics. my wife and kids went with me and I forgot the gopro.
to get the best wave I ended up with my front full 1200lb bag with about 500lb of Steel. and the port side 750 full and the starboard side with about 100 to 200 lb and the starboard tab all the way down.

This wake just as good as last year wake with and extra 800lbs usually I would put a 400lb sac on the front set and a 400lb sac on the back deck.

Now I know it works I am going to sample two other tab shapes one I am going to use plastic to mimic the Moomba auto flow tabs.
and the second I am going to bend the edges of extender tab down to create fins something like the surf assist.

[trayson]

Very cool. keep us updated.

[kirkman]

Awaiting to see this in action, Im needing a better surf wake also...

[wolff supra21v]

Not real happy this week had a good wave with plenty of push but wanted a little more length. I tried to length the wave by adding additional 400lbs to the nose of the boat and the wave looked real good but lost all its push. I am going to try and change the plates this week. Going to work on two types one to match the Moomba flow and one with a fins on the bottom to hopefully delay the water a little. Hoping to do some testing next weekend.

[icemanftr]

Not real happy this week had a good wave with plenty of push but wanted a little more length. I tried to length the wave by adding additional 400lbs to the nose of the boat and the wave looked real good but lost all its push. I am going to try and change the plates this week. Going to work on two types one to match the Moomba flow and one with a fins on the bottom to hopefully delay the water a little. Hoping to do some testing next weekend.

Any updates since May? Been pondering this Idea myself on my LSV.

[GT Canada]

Well shoot! I read through this whole thread in anticipation of some great results only to see it ends abruptly.

Does anyone have any further info on this? My guess is with the addition of some fins on the bottom of the plate it would have worked great!

[Leebo]

GT - I feel your pain, it’s like reading a great book only to find someone tore out the last 10 pages!

There’s probably more info on WakeGarage.com about retrofitting tabs/gates. Someone pls correct me if I’m wrong but gates are easier to dial in but are harder to install on an LSV hull. Tabs are easier to install, but need lots more ballast and then there’s the question of tab shape/dimensions.

A couple people there have built GSA-like tabs with success but are afraid to share the dimensions bc it’s patented…which is odd bc patents are in the public domain and the violation occurs when you reproduce for commercial gain.

It’s on my list to try to get these done this summer and my plan is to use the patent to get the dimensions- the big assumption is that they are drawn to scale. *some* of the angles are given and one of the dimensions. The text of the patent describes the optimal deployment at 10* but I believe most had better results at 5*

Here’s (https://patents.google.com/patent/US9545977B1/en) a link to the patent 9,545,977. If you build it first, pls let me know!!!

[sandm]

leebo,
I don't blame them for not putting stuff out there as so far every boat manuf. AND gsa have caved to lawsuits by 'bu and are paying patent royalties for every set used except skiers choice(afaik theirs is still pending and they haven't given in yet GO SKIERS!!!!) so not sure I'd want to be the little guy on the interwebs tossing out info on this.
I've read that patent before and can't say I remember it giving dimensions, only guides.

[Leebo]

sandm –

I hear ya, but we are talking about the opposite ends of the patent system. You’re referring to the commercial implementation of a patent and I totally agree – that is protected by a patent.

What I am referring to is the sharing of ideas surrounding a patent – ideas are in the public domain. Said differently, talking about the specifics of a patent is not protected, and for good reason. In order to be awarded a patent, the applicant needs to demonstrate their idea is non-obvious and contains no prior art. Sharing of ideas is the whole point of a forum – and talking about those ideas will help clarify whether something is non-obvious and/or help prove there may have been prior art. And as a side benefit to us, we *might* just advance the ball on these ideas and make a better system that isn’t protected by a patent (not holding my breath :cool: )

Now, whether you choose to take these ideas and implement them for personal use…that may or may not be protected. So the guys that said “Hey, I built my own GSA tabs” may not have avoided legal problems by saying “ but I can’t share the dimensions.”

As far as dimensions vs. guides, agree that what they give is pretty general, but I understand that’s there to protect someone from changing angles by a degree or two (or dimensions by a few mm) and calling it different (and circumventing the patent protection.)

For specific dimensions, this is what I read/interpreted and would love your feedback:


They list the end of the tab that mounts to the piano hinge as 17 ¾” with the inner angle as 81˚ and the outer angle as 99˚ (in the patent, column 7, rows 16-18 ).

Also, the critical part of the GSA tab – the fins at the end (referred to as a “hydro-thruster assembly” or “hydro-thruster diversion fins”) - are all 17˚ from the centerline of the boat and the tab deploys 12˚ from the centerline (column 12, rows 47-54).



Yup, I had to read 1400 lines of the patent to get the info contained in 11 lines… The rest of the dimensions/angles would need to be inferred from the drawings and you have to assume it was drawn to scale.

My guess is that the exact size of the tab is probably not as important as the angle the tab deploys and the angle of the hydro-thrusters (and the venturi effect of the volume change.) The amount the tab deploys is important but I would think you dial that in after adding ballast, and adjusting boat pitch/roll/speed.

THX!

[SONIC]

sandm –

I hear ya, but we are talking about the opposite ends of the patent system. You’re referring to the commercial implementation of a patent and I totally agree – that is protected by a patent.

What I am referring to is the sharing of ideas surrounding a patent – ideas are in the public domain. Said differently, talking about the specifics of a patent is not protected, and for good reason. In order to be awarded a patent, the applicant needs to demonstrate their idea is non-obvious and contains no prior art. Sharing of ideas is the whole point of a forum – and talking about those ideas will help clarify whether something is non-obvious and/or help prove there may have been prior art. And as a side benefit to us, we *might* just advance the ball on these ideas and make a better system that isn’t protected by a patent (not holding my breath :cool: )

Now, whether you choose to take these ideas and implement them for personal use…that may or may not be protected. So the guys that said “Hey, I built my own GSA tabs” may not have avoided legal problems by saying “ but I can’t share the dimensions.”

As far as dimensions vs. guides, agree that what they give is pretty general, but I understand that’s there to protect someone from changing angles by a degree or two (or dimensions by a few mm) and calling it different (and circumventing the patent protection.)

For specific dimensions, this is what I read/interpreted and would love your feedback:


They list the end of the tab that mounts to the piano hinge as 17 ¾” with the inner angle as 81˚ and the outer angle as 99˚ (in the patent, column 7, rows 16-18 ).

Also, the critical part of the GSA tab – the fins at the end (referred to as a “hydro-thruster assembly” or “hydro-thruster diversion fins”) - are all 17˚ from the centerline of the boat and the tab deploys 12˚ from the centerline (column 12, rows 47-54).



Yup, I had to read 1400 lines of the patent to get the info contained in 11 lines… The rest of the dimensions/angles would need to be inferred from the drawings and you have to assume it was drawn to scale.

My guess is that the exact size of the tab is probably not as important as the angle the tab deploys and the angle of the hydro-thrusters (and the venturi effect of the volume change.) The amount the tab deploys is important but I would think you dial that in after adding ballast, and adjusting boat pitch/roll/speed.

THX!

As one of "those guys"...
IMO if you have the skills to build them you can certainly drive over to a dealer with a tape measure and get some dimensions.
I'm not willing to risk having someone at sue-happy malibu or GSA throw a lawsuit at me, baseless or not.

To me "I built my own tabs" is one lost customer for them (potentially)
"hey entirety of the internet here are the dimensions and the step by step processes to make your own GSA tabs" is a potential loss of a lot of sales and a much bigger deal than "I built my own tabs"

If you're familiar with any type of patent law (or just law in general really) then you know that at the end of the day it has a lot more to do with who has more money and who is going to give up in order to quit hemorrhaging money first vs who is in the right.

If one of them did decide to file a lawsuit you're already out minimum 10k just to have a good lawyer write a response, none of which you're getting back unless you go to court spend 500K+ and win and then get your court costs covered. God forbid you lose, or run out of money somewhere along the line then you're just screwed while 'bu sits back and counts their pandemic profits lol.

To answer some of your questions:

The size is really not that important, people have had success with different sizes, GSA is a one size fits all job which is almost never the right fit for every application.

The correct size depends on your hull and your weight. You want to create just enough lift to cause the correct list angle without lifting so much you negate your ballast.

The deflector wings do create a nice wave but they are not the only way. Tige has moved away from the GSA tabs (likely didn't want to pay royalties to malibu and gsa at the same time after gsa lost their suit to bu) and their new tabs arguably make a better wave then the gsa they replaced, lots of people think so.

Supra swell waves are widely regarded as some of the best and they are using a very simple trim tab with a bend in it that would take 5 minutes to make.
Obviously the hull makes some difference as well but my point of there's a lot of ways to skin a cat and you likely won't go wrong if you wing it and build something that's based on any of the major systems.




|

[Leebo]

SONIC -

Thank you for the information. I did not see myself finding a boat w GSA retrofitted and out of the water for me to measure (at least nowhere close to me.)

Agree the fabrication is not the hard part, but to your point “the correct size depends on your hull and your weight.” I was pursuing the GSA size/style bc of the broad range of boats that have been successful with it.

If I understand it correctly, Tige used GSA in 2020 only. Is that right? There’s a dealer a little more than an hour from me. I’m guessing the GSA-style tabs will be obvious vs the newer tabs. THX!

[SONIC]

No problem,
Yes tige used gsa in 19 and 20 then switched to their new tabs in 21.
Their new ones are basically slightly longer gsa tabs without the diverter fins. I haven't ridden one yet but a lot of people are agreeing that they are better than the gsa version on the same boat.
30003

[sandm]

No problem,
Yes tige used gsa in 19 and 20 then switched to their new tabs in 21.
Their new ones are basically slightly longer gsa tabs without the diverter fins. I haven't ridden one yet but a lot of people are agreeing that they are better than the gsa version on the same boat.
30003

my cousin's 2021 23zx uses gsa tabs and all the '21's I have seen have gsa. tige forums listed earlier this year that tige switched to their own tabs on the reintroduced z3 hull but as of spring were still using gsa on everything else. looks like they switched mid year '21 and you're right, tabs look similar to the old taps3 tabs only have sides on them like gsa but missing the vertical fins at the end.
sure the TO forum will light up with comments once people have time on them. there will be gsa tabs for sale from people thinking the new tabs are better than gsa but my guess is as you commented, ditching gsa and moving in-house are financial in nature, not because their new tabs are "game changing".