Couple of other points;
A twist in the bladder, which often occurs near the wing tip, is the classic cause of this (same issue if the bladder is stuffed-in and traps itself and not allowed to fill the LE correctly).
Make sure the bladder is inserted with no twists and secured to the wing tip - usually by the fold to anchor the Velcro. - Some kites have a zip and an anchor loop inside.
This will stop the bladder creeping away from the wing tip in general use - as per dejavu's point.
I mark what I think should be the 'inside' of the bladder with a sharpie and check this is the right way after pulling bladder through - This helps, but not if you've put a 360 deg twist in it! which would be very careless!
The first inflate after install is really important and should be done very carefully, with regular stopping and shaking/gentle manipulation of the LE to ensure the bladder is sitting correctly.
If you feel any kind of void in LE during this first pump, consider stopping as the bladder may over-stretch to fill it. You may need to remove bladder and try again.
Good luck with your repair.
I find doing them when I have plenty of time and someone to feed the bladder in as I pull really helps.
CaptainArgh wrote: ↑
Wed Nov 08, 2017 10:38 pm
When you reinsert the LE bladder, you should have a good amount of extra bladder material at the tips. Don't roll it. When I've had to get in there for a repair, I fold up the bladder tips like an accordion so it can expand as needed.
If you have to remove the entire bladder for some reason, it'll stretch around the inside wingtip corners (if you have them). And when you inflate the bladder for the first time it'll pull back from the tips of the kite as it fills the void in the corners. Years ago I got a few blow-outs in my Fuel wing tips because I was rolling the end of the bladder instead of an accordion fold (which you loosely stuff back into the wing tips). So, if you have a corner anywhere in your LE, you may want to reach in there and pull it back into the void to make sure there is slack there as well.
But yeah, what's happening is the wing tips have pulled back for some reason. They are expanding to fill the space with a bubble which blows out. Bubble may have been happily filling the void for many years until the thinned material failed on you.