Yes they are, pretty neat technique to inflate your clothes for extra buoyancy
Think it's better to get a porosity test done by a paraglider certification center or someone who has such device. Best thing that comes close is to try and roll up the kite with the vents closed or try to breathe through the dry cloth. Easier if you have a brand new kite for comparison.
I don't think you can test the porosity of a kite when it is wet, I bet you will find the same leaky seams on a fresh kite.
A friend of mine found this product : https://www.sail-and-kite.com/english/s ... e-coating/
Data sheet says it is activated polysiloxane in water , 2k+water
It could be a "new" chemical cross linking between this kind of silicon to the cloth.
Don't know if he allready purchased this stuff. I will report how it turned out.
What do you guys think about that coating method?
These users thanked the author Breze for the post:
I just watched the porosity test for paragliders what they do is make a vacuum and measure it. I think it's possible to do the exact same test with a simple hand pump and air gauge. I'll give it a try later should be instructive
Used the GE Supreme Silicone on a test area on my 12m Soul and after curing 24 hours I did the "breath test". The seams were totally air tight in the area where I applied the silicone, much better than before. So I am proceeding with treating the rest of the kite. By the way, when I applied the silicone I gently pulled the seams to expose the thread holes and pushed the silicone into them with my finger. I'm just doing a modest section of the kite when I have time, so it may be a week or so when I am done. I'll post the results when I am done.
Regarding the activated polysiloxane in water, I don't see it doing much for seams, but possibly for the porosity of the fabric.
These users thanked the author JakeFarley for the post:
I just put my t-shirt in the water and blew it up, pretty cool. It still leaks but so much less when it's wet.
Wait. Isn’t this the solution that you were looking for? Crash your kite periodically, to keep it wet. Then no problem, it will be like new.
Another way to test: inflate your kite with a leaf blower, maybe fold in two, then put a weight on it (some cardboard? etc.), and time how long it takes for the air to get out (kite becomes flat). You’d need a new kite to compare. I’d suspect part of the cloth is to blame.
I finally finished sealing the seams (leading edge, almost all the upper surface except near the trailing edge) on my 12m Soul. Took one 10 oz. tube. I got some decent wind to test it in (12-15 knots) yesterday. It seemed to make a significant difference in my jumps (more floaty) as well as the low end power (I guess because the kite holds it shape better not leaking air in lighter winds?). Also, it did not deflate on the beach quickly like it did before. I'm pretty much satisfied that it was worth it. I'm not sure if I should take the time to seal the seams near the trailing edge.
If you do not want or have time to treat all seams, i would bet that the area to treat in priority regarding the pressure losses , thus the pressure inside kite, are:
The extrado before intrado
As seams closed to the air entry.
This is were the pressure differential is the highest, from "physics and logical". Rapid approach
I went back and sealed all the seams front and back. It takes forever but it's worth it. I also have a pressure tester now, but probably won't bother to use it to test my kites because all my kites are working pretty good.
