The only time I have any raveling at all is if I have a quilt top hanging around a long time before I quilt it and handle it a lot (show and tell, trying to decide quilting pattern etc.). But normally I have almost no raveling. Do you handle your blocks a lot, for instance sew in the dining room and put everything away every day? All I can think of is get a container that will hold your finished blocks. As you make the blocks put them in the container and don't touch them until you are ready to join them. I am careful to cut on the straight of grain, which will reduce fraying. Most of my fabrics are from quilt shops, but I also use some from JoAnns and WM. I'm curious to see what others say. I hate piecing with pinked fabrics, as I can never figure out my seam allowance.