This wasn't a problem for a while; my jeans were getting generally worn and faded out of "good clothes" usefulness faster than the knees were ripping through once I started wearing them for "old clothes" uses. But then I started exercising on climbing walls, and that changed very quickly -- I have at least a half-dozen jeans that would be great for climbing except that they've got a big rip across the knee, and a couple of pairs of good jeans that I don't want to subject to abrasive stuccoed walls.
I tried simply sewing up the rips, pinching them together and stitching across the gap. This works for a week or three, but then pretty quickly pulls the crosswise threads out and there's a hole again.
So, those of you with experience in the ways of fabric: What's the right way to repair a large rip in the knee of a pair of jeans? I don't really care about aesthetics, but I do want something that I can use actively and which won't rip out.
Crossposted from Dreamwidth (original here), with