Examine the ravelling edge and check the threads where the seam is. Are the threads nice and close like the fabric that is further in? If not you may want to take them off and neaten the edge with your rotary cutter. I like to cut about 1/2 inch off after ripping border pieces. Ripping to me seems to open up the weave on the edge and I don't like it. It is up to you if you think it may not hold, then perhaps you better fix it.