
Originally Posted by
eZentai
If it's nylon lycra you must use polyester thread. Cotton or silk threads don't have the strength to match nylon material, and they sometimes loosen or even break if there's significant stretching of the material. If it's cotton lycra you can use cotton thread or polyester, but I've still found that polyester is better even for cotton lycra. Silk thread won't work for cotton lycra.
If you're darning a small circular hole, just do it the same way you would a hole in anything else. If you're repairing a seam or sewing up a cut in the material, remember to set you machine to use a stretch stitch, not the standard linear stitch.
The best thread, if you can get it and have a machine that can handle it is the new stretch thread, but it's hard to find a store that carries it. It can be ordered on the internet, though, do a google search for terms like order stretch thread.