I have had regular cotton quilting fabric fray very badly. Later, I realized that the weave was way too loose. I tamed the problem by sewing 2 seams each time. One was the regular 1/4" seam and the next was a 1/8" from the outside. I, also, shortened up the stitch length and I always use a 50 wt thread. I made sure the block was going to be the right size before I sewed the second 1/8" stitch. I did not make sure I stayed a true 1/8" because I wanted it to vary so I didn't loose any more threads from the fabric. My machine has an over edge stitch similar to a serger, but the fraying stopped with the second seam.