My first speed loom patch, on a pair of merino wool leggings with a HUGE hole in the knee and run down the leg. I figured this item was destined to become rags, with a hole probably too big to patch, which is why I chose it for my first experiment. Not bad actually! The run is still there but I could probably get another year of wear out of this thing. The 50% wool/50% acrylic floss/yarn I chose is very fray-y and shed-y, and comes unwound easily. I can see it shedding and frizzing off, but if it felts that's good, will make a stronger patch. If I were serious about patching I'd use black to match the fabric, but I wanted to see my work. Next time I'll stick with a square shape like you're supposed to.