Wednesday, April 20, 2011

Kitesurfing: Leading Edge Blowup Kite Repair

(experimental, ie do not follow)

My Flexifoil Ion3 9m blew up. To add insult to the injury it blew up on the beach, in my hands when I was inverting it to pack and go home. Darn! Looks terrible. I simply think it just got old and tried to quit on me. No such luck, buddy! The quitting I mean, not getting old.

So here is my attempted, DIYig (DIY in garage) revival report. Some things worked, some were messed up. I am yet to try to fly it...


The repair was a two step process: the bladder and the canopy. Since I am lazy by nature I decide not to pull out the bladder completely but just slide it out of the tip. This was possible since the damage was close to the tip.
So here it is, the bladder with a fist-size hole. They say, cut it open and glue a patch from the inside. I say no need to fix a hole by creating another hole.



I removed the air connection from only one strut and rolled the bladder so it does not get in the way.Then I used some sticks to stretch damage area.

I used a bigger-then-palm patch out of an old bladder and put it into the bladder through existing opening (technical term to describe a hole). Just made the patch way oversize so when glued with AquaSeal, the glue would not have a chance to glue the bladder's walls together. Here the black marks the edges of the patch (it's inside the balder). The glue already applied through the hole (I have cut out the original damaged area from the blown-out material).


I have also applied another patch from the outside. I have spread the glue to keep the edges of the outside patch glued to the bladder.

After 12 hours under load, the glue turned yellow. I have not used AquaSeal before so I have not idea if this is OK....It feels flexible and strong.

This is how it looks like cured.

Anyway, the only other problem was that there were small pockets of air left between the patches. But is this a problem really?

This part was relatively easy. The stitching required patience and a lot of ...
Here it is, the top seam opened to make more space for sewing. I had only a fairly thick dacron from my boating days. I have also used the double sided sewing tape 3/4" (the white strips already attached to the edges of the damage. I have decided to put a single band of dacron and sew it in.


In order to help with alignment I first applied a insignia cloth to the outside. This helps keeping the edges together and in good place.

Then I placed the dacron into the double sticky tape. The insignia cloth was a second take idea. I found that the sewing tape is not sticky enough to hold the edges together.


Sewing the seeds of love..ahem...adjusting my flaky walking foot machine is always a challenge, esp when I have not used it for a few years. She's got rusty, so did I.

Four rows of zig-zag from the edge to the edge. I had to rip it out only once when the sail cloth got sewn in. Only once I swear!
Then I got a brilliant idea to strengthen the cloth and put a spinnaker repair tape around the edges. Esthetic's got lost in the process (the tape is white).
But where did the bladder go? I dropped it rolled into the LE shoulder. Kept it nicely out of the way.

Sew him up, doc! I had to get the bladder out. Stretch it and somehow pray I will not sew it in while closing the leading edge.

Here, under (minor) pressure test....It worked!. Just royally miscalculated (read "screw up") one small detail. The edges got quite strong with extra spinnaker tape and with the dacron (see: it is nicely going all the way from edge to edge). But...unfortunately, the dacron I used way thicker then the original cloth and hence I could not fold it. Darn!  This made the repair downright ugly...


the good


This is plausible result. Kite survived nightly pressure test. and looks fine on the outside.




the bad and the ugly

Note the LE deformation. I suspect it could be a result of original damage and/or my sewing. It looks like the circumference is smaller in this area. Perhaps, I should redo the top seam. One day. Perhaps.

Oh, well. I only meant the repair as an experiment....I do not think I'd take it into waves anymore. But on flats or as a learning kite it is still OK.

1 comment:

Joe said...

Thanks for taking the time to write that. Good info to know.
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