Postby foilholio » Sat Sep 01, 2018 1:10 am
Similar weight fabric say 32-40grams m2. Best to use precoated kite fabric, you can find it on ebay. Nylon is fine. White is best.
Use 1/2 inch very thin double sided tape. Craft store have it. 2 side by side strips of tape on the fabric near edge, long enough to cover hole with 1/2inch+ overlap at the end. Cut out the fabric tape you now made.
Apply to inside of cut with rip in the middle. Apply one side ( peel one side) of the fabric tape at a time so you can carefully match the other side. If the cut is crooked , just use multiple pieces of the fabric tape and overlap. Good to make some excess for that. Make sure you don't have creases or bubbles when you apply the tape. If you do, redo that bit, best spot it when you first do it as it can throw out aligning later. Use the ripstop lines and frayed fabric to help align the rip. Some rips can be missing a little fabric in the middle. Look at the fray ends to help.
Sew a 3 step zig zag once around the edge of rip, not going into the rip. You want to stay withing the edge of the tape, or more stay in the middle between tape outside and rip. Then the same zig zag along rip twice, with alternating pattern so the zigzags don't match. You want this to hold the rip edge onto the tape, hence zigzags alternate and cross the rip edges more.
If you have trouble getting access thru the kite to the rip to sew or put it together, open(pick stitching) the cell - outer skin(with rip) seam near the rip where there is no internal structures. You want this to be a plain seam (no internal structures) so you can sewn it back together easy. Avoid opening the TE as the seam there is complicated. You should be able to sewn the seam, and gain general access thru the vents LE and TE and holes in the cell walls.
Repairing foils is not easy.
For a quick temporary repair that actually lasts a while, you can just apply sail tape inside and out. Some people use sail tape and stitch it, but the weights of it are wrong and it has no coating so porous.