Power Kite Forum

Waterproofing an older Flysurfer speed 3

yeti - 8-8-2014 at 05:57 PM

Album updated with front skin procedure used
http://imgur.com/a/Wv8gI
I didn't have enough Tent Sure and after some careful thinking I decided on a different approach for the front skin.

original post

After speaking with John (from powerzonekitesports) a couple months ago I decided to do a little project with my Speed 3. I thought I would share the progress in case anyone else might want to try this. Should work great for any kite that isn't quite as air/water-tight as it should be.

I bought the kite used almost a year ago and it had already lost the water resistance. The fabric wasn't crispy at all either and it didn't hold air all that well. I only wanted it for snow/land so I figured it would be fine. Well the day has come when I'm willing to use it on water, plus I figured doing this treatment would extend the life a little longer in general.

Anyway, the only materials you would need are as follows:

* Tent-sure (1 bottle seems to cover about 5 or 6 square metres. I needed almost 3 for one skin of the 15m kite)
* Binder clips (almost any size will do; I used approx 3/4" size)
* Some line. Twine, string, rope or whatever.
* a basic table fan
* space and some kind of large fixed objects to support the kite at either end

The line and clip part is probably optional. This is the part that I sort of invented as I went. When I spoke with John, he gave me all the general info about using a fan and doing the kite in small sections. I wanted to do as much as possible in one shot, and avoid using a fan at all if possible. I am not sure if the method I used actually helps the whole project, but it definitely allows me to keep the (recently) cleaned fabric off the ground and dirt-free, ready for the tent sure application.

In the pictures below you'll see I started with the back side of the kite. In theory I wouldn't need clips for the front side, because I could just hang the kite from the bridle lines. I might still use them because the supporting lines are tied in a way that is very easy to adjust (sliding knots). Makes it much easier to position the wing exactly how you want it. Once the rigging is all set up it's not very hard to move the clips around to attach the next part of the kite.

Someone might want to try this some time using an air brush for super quick application. Like I mentioned in the image captions, the small fan is easily able to keep about 75% of the kite inflated (even on low), so if I unrolled and hung the rest of the kite up, I could probably paint the entire side in one pass. For reference, it took about 2-3 hours of painting for just 1/2 of the back side (once the support rigging was set up).

Here's a small album:
http://imgur.com/a/Wv8gI


front skin update

I realized I wasn't going to be able to get enough tent-sure to do the front side. I had about 1.2 bottles left. It took almost 3 bottles to do the back skin. I figured the local stores would have it restocked since I bough it over a week ago, but it's been on back order everywhere. I wasn't going to get it shipped in from across the continent since it would be double the cost for a bottle. They're $10 at the local MEC (similar to REI for you 'muricans). I wanted to avoid having this turn into a multi-week project as well since it uses up a lot of time and space.

I had read about using silicone dissolved in turpentine. Seemed like an OK approach, so I tested some small pieces and it worked pretty good. I didn't actually use turpentine, but it might actually be the best choice. Instead I used a mixture of mineral spirits (similar to turpentine but not as volatile) and naphtha (very volatile and dries fast). I didn't expect the silicone to seal air holes as well, but since the back side should have been the worst, I was hoping the front side wouldn't need something as thick. If you have an air holding problem, you might want to stick with the Tent Sure for both sides. Most of my gripes were with the water-proofing situation.

There are a couple advantages to the silicone treatment over Tent Sure. Some of these I knew up front, others I discovered along the way.

* The silicone solution is very easy to apply. Only takes about 2-3 hours to thoroughly paint an entire skin. Possibly could be sprayed on with an air brush or a spray bottle, whereas Tent Sure would be much harder to do that way and probably wouldn't go on evenly if you did.

* The silicone dries a lot quicker. It also doesn't glue together fabric as aggressively as the Tent Sure. You can do a once-over of the whole kite after about 30 minutes of drying and gently pull apart any fabric pieces that stick to each other. With tent-sure, the fabric will come apart too but it is more difficult to get apart and it leaves some gooey looking residue when two pieces stick together.

* The silicone treatment should be very UV resistant. I am pretty sure that since Tent Sure is urethane based it is much less UV resistant. It is also meant for tent floors so it probably doesn't have any UV additive (it doesn't say anything about UV on the bottle)

* The silicone treatment is probably lighter overall in terms of weight

* It is easy to apply multiple coats of silicone solution if you really want extra durability since it dries so fast. New coats can be added after 30-60 minutes.

The solution I used was about 300 ml naphtha to 150ml mineral spirits and probably 2-4 tablespoons of silicone. (A large blob). I had to shake this vigorously in a small bottle for about 5-10 minutes to get 90% of the silicone to dissolve. Some silicone bits were left on the bottom of the bottle. Eventually it dissolved but if you get to that point, there is plenty of silicone in solution and your kite will end up very waterproof. I imagine you can still thin it out more by using more mineral spirits or naphtha if you really want to save weight. The solvents will evaporate entirely leaving you with only silicone (and some of it probably evaporates when it cures). I used about 35-40% of the tube pictured in the album to do one skin. Total weight added to a 15m kite should therefore be somewhat less than the whole tube weighs.

Oh by the way, the reason for using a combo of solvents is to balance the drying time. With mineral spirits only it seemed like it would take way too long to dry. Once it dries then I assume the silicone starts curing. Mineral spirits seem to take a couple of hours to dry completely. If you use a lighter solvent like naphtha drying is much faster. Too fast, actually, so mix in a heavier solvent like turpentine or mineral spirits to balance it out. Maybe if you were spraying, you could get away with pure naphtha. Make sure whatever solvent you use does not attack nylon! Also make sure you test that it dissolves the silicone you choose and that it does actually end up waterproofing the fabric before you go to the trouble to cover the whole kite.

caution: naphtha vapors are explosive; and any of these solvent vapors are bad to breathe. do this with more ventilation than you think you need. Also get a box of nitrile gloves to protect your hands. Naphtha is not good on your skin. Mineral spirits aren't as bad but you sill dont want that stuff all over you. A small box of disposable gloves is the best way to go.

Anyway... to apply the solution, I just dumped out 50ml at a time into a small HPDE plastic container (bottom cut off a plastic jug) and used a sponge brush to paint it on. It goes on extremely quick compared to Tent Sure because it's much thinner. I think when you're painting instead of spraying you'll have to deal with a little bit less of the vapors.

This concludes my waterproofing project. Since I have Tent Sure on the back and silicone on the front I guess I'll see how they both hold up over the next couple of years. Hope this helps someone eventually.

ssayre - 8-8-2014 at 06:10 PM

What is it's consistency like? What did you use to apply it. Do you think you could use an empty windex bottle for application?

SpecialK - 8-8-2014 at 07:32 PM

This is totally awesome. Thanks for sharing. I recently got a speed 3 (that's actually on it's way back from john tuning it). It also has lost its waterproofing.

How did it affect the kite's performance? I can't wait to hear...

yeti - 9-8-2014 at 04:32 AM

I promise I will make another update in this thread once I completely finish the job and have had a chance to fly it.

Initially, I have part of the kite covered and you can tell the color is obviously different in the photos. But also it does seem like it is holding air better already. The water proofing should definitely be good. It doesn't seem like you need a very thick coat to achieve that. After like 4-5 hours of drying the fabric already feels crispy/crinkly again instead of that mushy, soft, silky feeling that everyone who owns one is probably familiar with.

One note worth mentioning is to make sure you keep the coat thin and work fast. If you leave a thick layer as you're painting and it starts to dry you'll end up with a gummy residue that almost peels off the skin. (Starts to set up in maybe 5 minutes)

If I have some left over I will try the windex spray bottle trick on a test piece and see how that works. It's actually something I never thought of, but I worry that the fluid might be too thick and it will probably clog the sprayer once you stop, so you'd need to flush it with water or solvent after you finish one section.

The other possibility is maybe thinning the stuff with a little water. I actually contacted the manufacturer and they said not to thin it or it might affect how it cures. I have actually used a little bit of clean water (filtered, but distilled would be better) to thin it slightly and it didn't seem to affect anything. It's a water-based urethane so it seems like it would make sense. If you thin it too much it probably just won't have enough of the urethane to actually bond together as a coating, so might want to test it yourself if you need to thin it say for an air-brush or a ghetto-airbrush (spray bottle).

SpecialK asked me about the weight. John could probably answer it better, since from what I have heard, it sounds like he has probably done this a few times, maybe not exactly the same way. If you do the math though, I think I will use about 5-6 bottles. That should add up to just over 2 pounds of fluid total. You do have to remember that as it dries, a lot of water evaporates so maybe it only adds about half that weight. Someone should get a kitchen scale or something and try it with a test piece to measure the wet-dry ratio.

yeti - 9-8-2014 at 04:35 AM

Quote: Originally posted by ssayre  
What is it's consistency like? What did you use to apply it. Do you think you could use an empty windex bottle for application?


Maybe I forgot to mention I just used the provided sponge brush that comes with every bottle. I went through about 1.5 bottles per brush so far, so you actually have extra brushes. Plus those brushes are dirt cheap anyway.

Using water, I was able to rinse the brush every hour or so because the coating would start to sort of dry on the sponge.

powerzone - 9-8-2014 at 10:30 PM

this is a great write up about the process. excellent job. the 'added weight' after it all dries is negligible . far less than the water weight it would take on the second it gets wet.

yeti - 10-8-2014 at 09:43 AM

General update
I have been trying to do the front side but all the local stores have run out of tent-sure. I bought the last 4 bottles when I started the back side, so now I am twiddling my thumbs wondering if I should thin the last 1.2 bottles and try to cover the front, or wait for a new shipment.

Quote: Originally posted by powerzone  
the 'added weight' after it all dries is negligible . far less than the water weight it would take on the second it gets wet.


Definitely less than the weight of wet for sure. It was great being the only one riding in light wind. Except the snow shut me down once. All it took was a light snow and every flake that hit the kite melted and stuck. Eventually it wouldn't even launch in the light wind and I had to pack it up wet and go home.

propylene22 - 10-8-2014 at 10:35 AM

I used a bottle of nickwax techwash direct to re-waterproof a flysurfer psycho 3 and it worked fairly well.

yeti - 11-8-2014 at 05:02 PM

So I posted some updates. Quite a lot of info in there. Post any questions and I'll try to fill in the gaps. New pics are up too.

My project is complete once I let everything finish curing today and I take it for a test flight tomorrow (or soon).

About the nikwax... I have used that stuff on things like jackets and other equipment and it seems like it wears off a little quick. It's also not quite as cheap as the silicone treatment I mixed myself, and I think (not sure) that one of its features is that it is breathable. Silicone applied this way should not be breathable (although it probably won't plug the larger holes like at the seams) and that's what I really wanted.

Most of the consumer-grade waterproofing treatments are probably just fine if you just need a little more water resistance, but for kites that have had a lot of use like mine, I would definitely aim for something a bit more heavy duty. I think I can trust what John says about Tent Sure so far. It seems like the heaviest-dutiest thing for serious reconditioning.

3shot - 11-8-2014 at 05:43 PM

That silicone recipe sounds pretty good!!
Thanks for the write up yeti!!

yeti - 11-8-2014 at 07:58 PM

Quote: Originally posted by 3shot  
That silicone recipe sounds pretty good!!
Thanks for the write up yeti!!


Thanks. I better give credit to the thread that provided some of the info I used: http://www.foilzone.com/phpbb3/viewtopic.php?f=1&t=10648

SpecialK - 11-8-2014 at 08:22 PM

Wow this is amazing info. Thanks for taking the time to post all this. What kind of background do you have to know about naphthalene.. This is nothing I'd likely think of on my own!

yeti - 12-8-2014 at 04:23 AM

[s]naphthalene[/s] naphtha

Had to correct this. It is obviously not naphthalene since that's a solid petroleum derivative, and the picture I included was of coleman camp fuel.

Not sure why I wrote naphthalene, but it was late last night.

yeti - 12-8-2014 at 04:47 AM

Quote: Originally posted by SpecialK  
Wow this is amazing info. Thanks for taking the time to post all this. What kind of background do you have to know about naphthalene.. This is nothing I'd likely think of on my own!


I wouldn't say I have a background in anything special. The choice for using naphtha was (A) I had some, and it's relatively inexpensive in camp fuel form
(B) Google told me it could dissolve silicone (apparently some people use this to paint silicone onto other things)
(C) it's not as harsh of a solvent as some of my other options which were either lacquer thinner (xylene/toluene) or acetone.

Those other solvents can do amazing things like dissolve glue or soften rubber or eat styrofoam, and I wasn't prepared to take the risk of damaging something on the kite. Nylon is pretty tough when it comes to solvents, but there are stitches, probably some glue in there somewhere, maybe even some polyester somewhere, I dunno.

I am googling more now and I see that rubbing alcohol (the isopropyl kind) might also work. It evaporates fast and is also much less toxic compared to naphtha so long as you don't drink it. Someone might want to use it for thinning instead of naphtha. But always test first.

abkayak - 12-8-2014 at 05:05 AM

rustoleum neverwet..........anyone play w/ this stuff yet?

3shot - 12-8-2014 at 09:02 AM

I think Kober posted about it awhile back??

3shot - 12-8-2014 at 03:24 PM

Has anyone looked into the Kiwi line? I'm sure its been discussed before.
I was looking at these:

http://www.kiwicampdry.com/performance-fabric-protector.aspx

http://www.kiwicampdry.com/patio-fabric-protector.aspx

States for nylon, etc.

Kamikuza - 12-8-2014 at 04:44 PM

The Nikwax stuff just sounds easier to do... we barely have the space to lay out the kite on the lawn, and there's no garage here :(

... how much wound you charge to silicon a kite? :D

yeti - 12-8-2014 at 06:36 PM

If I were going to do someone's kite with silicone it would be like a solid two days work for me at this point. So probably at least a few hundred bucks not including shipping. Not gonna get into that anyway. Shipping across borders is totally not worth it, so unless you're in my back yard (I should do it for free, neighbor, come over for a beer), no dice.

That being said, I think if you want to go the silicone route, there's an easier way. If you can go where you normally fly the kite, just get like a 2L coke bottle and make like 1L per 10m^2. Bring a plastic spray bottle with you and go nuts on the kite while it is lying on the grass. Once you're done, fly it dry. Land and do the other side. Repeat fly-dry. I am willing to bet this will work almost flawlessly. If you use the quick curing silicone (I think mine was) and not too heavy of a solvent, that stuff will be tack-free within 30 minutes of static flying. I don't recommend packing it up tightly afterward. Maybe just lay it out, put a sandbag on the corner and have a picnic before you pack it up.

If you wanna Tent-Sure it though, that stuff is a huge pain and there's no way around the waiting time.

Maybe if you only have a 7-10m kite you could do the nikwax fairly quickly. I know mine was a giant pain to wash. I washed it in a plastic kiddie pool that my dog used to use and there's no way I could even get more than half of it into the pool at a time. Then taking it out is a big pain cause it's hard to get all the water to drain out from inside the skins.

Really depends on what you're going for. I wanted to have some air sealing too (besides water proofing) and I think a paint or spray-on product that cures on the surface will do a better job at air-sealing than a wash-in product.

Good luck with whatever you choose. I suppose it could make sense to go for the easier option first. Less time and effort wasted if it doesn't work out. You always have non-water-based options as a fall back.

yeti - 12-8-2014 at 06:55 PM

test flight and performance update

There was like no wind today but I took it for a flight anyway to see whether performance was affected.

http://imgur.com/a/Wv8gI#AiWBFHe

Things are lookin' good. You can land the kite and there's plenty of air left after waiting a few minutes. Probably nothing like when it was brand new, but the sealed fabric must be making a difference. A couple more coats of tent-sure around the seams might make it even better, but I am happy with how it turned out.

In the 3mph breeze today, all I had to do was walk backwards. A couple of quick tugs got it off the ground and inflation was complete after only a couple of passes across the sky. The wingtips definitely stay fuller now. They used to get all floppy in light wind, but I think that problem is improved the most. The kite must not be much heavier. Probably helps to have that extra wing area from full inflation.

Anyway that's like pretty much everything I wanted to do now and it may not be brand new, but it's definitely something I am willing to try in the water now, and the winter will be a whole lot better since the kite should stay a lot more dry in snow.

3shot - 12-8-2014 at 07:06 PM

:cool::thumbup:

yeti - 12-8-2014 at 07:09 PM

Quote: Originally posted by 3shot  
Has anyone looked into the Kiwi line? I'm sure its been discussed before.
I was looking at these:

http://www.kiwicampdry.com/performance-fabric-protector.aspx

http://www.kiwicampdry.com/patio-fabric-protector.aspx

States for nylon, etc.


In addition to what are probably an endless supply of sprays and washes for waterproofing, I read about some kind of aerospace-grade waterproofing from a brand called 303. Forget where I saw it. Sounds possibly good too. Here's a link on amazon
http://www.amazon.com/303-30313-Aerospace-Protectant-fl/dp/B...

SpecialK - 12-8-2014 at 08:16 PM

Totally awesome thread. Keeps getting better.

Since there's so many smart minds here, let me pose this to the group.

I posted pics of my kite a while back:


As you can see it's fairly yellow. The previous owner flew it a lot in northern fresh water, resulting in the yellowing of what should be white.

Any suggestions on what might restore it to its former glory? Or is it too much hassle to bother?

I'm pretty sure I'm gonna be doing some kind of waterproofing. Not sure which method yet, but yeti has inspired me!

yeti - 13-8-2014 at 05:00 AM

If you think the yellow is from dirt, it might be good to try to wash it first. Who knows? It might reduce the weight.

My front skin was mostly white, but my back skin was yellow and no amount of cleaning would solve that. I am pretty UV has damaged the actual fabric over time. Just like what happens with most plastics. You see it in white colors easiest, but you can bet the other panels have about the same amount of UV damage.

If you don't have a serious air-holding problem then maybe all you want is a simple water proofing of some kind and maybe throw in some UV treatment if the water proofing you choose doesn't include it.

I think sealing up the fabric with something will still improve the flying performance more than you might expect, unless it does actually hold air really well. Maybe John has already fixed it for you by tuning it?

SpecialK - 13-8-2014 at 05:52 AM

We will see! It gets delivered today :)

So if you were to start again, would you do the whole thing with tent-sure or your awesome silicone invention?

ssayre - 13-8-2014 at 06:18 AM

Yeti, is the silicone you used actually 100% silicone or are you using silicone as a general term. From your picture, it said it was a thermoplastic roof patch.

yeti - 13-8-2014 at 08:19 PM

Quote: Originally posted by SpecialK  
So if you were to start again, would you do the whole thing with tent-sure or your awesome silicone invention?


I think I'd make sure I had enough tent-sure to finish the job first. I think it was better to use that on the worst skin (back side), but I don't really have a good way to measure the result. I also have some trust for what John says about it being the best thing to do. Since I had everything set up to do the back side, doing the front was only gonna cost me a few extra hours total, but I just ran out of bottles. I think the silicone thing has the potential to be much faster though, whereas tent sure does not.

With the silicone solution you don't really need to do as much setup because it doesn't have the problem of sticking to itself as much. As long as you pull it apart in the first 30-60 minutes it never seems to stick back together. And only about 2-3 hours to paint an entire side. Probably faster if you spray with a bottle or something.

What you choose probably just depends on what trade offs you're willing to live with. Like most things, in this case the more effort you put in the better it will turn out. But twice as much effort won't make it twice as good, unfortunately.

yeti - 13-8-2014 at 08:43 PM

Quote: Originally posted by ssayre  
Yeti, is the silicone you used actually 100% silicone or are you using silicone as a general term. From your picture, it said it was a thermoplastic roof patch.


At first I thought it would be a urethane based product because it said that. I am pretty sure it's just a quick setting silicone though. Any silicone would do and you can get a sense of the curing time on the side of the tube. Note that since you're thinning it and applying a very thin layer, it actually cures a lot quicker than it would if you were caulking your bathtub. Once any solvent evaporates the vapors that come out of the silicone that cause it to cure have a very easy time escaping since it's applied so thinly.

Not sure why the call it a "thermoplastic". That implies a whole bunch of special properties, very few of which this stuff actually has.

I don't think it actually says exactly what it is, but I chose it because it was clear, flexible, could be painted on something wet, sets fast and also could be painted over after curing.

I wish I could get more info on this somehow, but I'd just go with whatever silicone is clear and promises to stay flexible. I think a patch silicone for roofing is probably just better formulated for that type of thing. In your bathroom it probably doesn't need to maintain as much flexibility after curing, or resist environmental factors as much (other than water which they all do).

yeti - 30-9-2014 at 06:43 AM

One final update for this thread. I felt like I may have kept some people waiting on the results. I didn't even have a chance to use the kite in August but now that Sept is over, I've had it out in the water a few times during 8-12 knot days. It'll definitely pull me on a light wind board in 8 knots. Lots of fun at 12 knots on a regular board.

I've crashed it few times and the only time it didn't relaunch was when it crashed due to the wind dying. Even that time I was able to drag it back to the beach and stand it up on the sand and relaunch it right away. So based on this I'm gonna have to declare the project a success.

Last weekend I was able to take some pictures of a local instructor trying my Speed 3, so here's an album that includes some shots of the kite. http://imgur.com/a/dQDc1

SpecialK - 1-10-2014 at 01:38 PM

Thanks for the follow up. I've kept this link handy for the future, but I've been too busy to actually do any kiting recently. Seeing those pictures makes me really wish I could get out on water (never done it yet, only land).

PistolPete - 16-2-2017 at 01:01 PM

This topic got me thinking a few years back about re-coating kites so I thought I'd share on PKF another coating idea and my findings .

ssayre - 17-2-2017 at 04:37 AM

Quote: Originally posted by PistolPete  
This topic got me thinking a few years back about re-coating kites so I thought I'd share on PKF another coating idea and my findings .


In the commercial roofing industry, we primarily use poly ether and poly urethane sealants. Both are moisture curing. we use silicone to a much lesser extent.

I didn't recognize the marine goop you used. Is that more of a butyl?

PistolPete - 17-2-2017 at 08:50 AM

Quote: Originally posted by ssayre  
Quote: Originally posted by PistolPete AKA Puget Sound Kiter  
This topic got me thinking a few years back about re-coating kites so I thought I'd share on PKF another coating idea and my findings .


In the commercial roofing industry, we primarily use poly ether and poly urethane sealants. Both are moisture curing. we use silicone to a much lesser extent.

I didn't recognize the marine goop you used. Is that more of a butyl?


Coating ends up being styrene butadiene rubber when cured.

ssayre - 17-2-2017 at 10:59 AM

Quote: Originally posted by PistolPete  
Quote: Originally posted by ssayre  
Quote: Originally posted by PistolPete AKA Puget Sound Kiter  
This topic got me thinking a few years back about re-coating kites so I thought I'd share on PKF another coating idea and my findings .


In the commercial roofing industry, we primarily use poly ether and poly urethane sealants. Both are moisture curing. we use silicone to a much lesser extent.

I didn't recognize the marine goop you used. Is that more of a butyl?


Coating ends up being styrene butadiene rubber when cured.


Styrene butadiene is added to specialty asphalt based roofing products for impact resistance. I think I have seen it in caulk tube form but haven't used it. I'll have to play around with that.