sharp edge of the fabric is cut and folded to form a hem before being fed by an operator or by other means to machine 1 the machine 1 stitches the hem of the fabric 2 with needles 3 to form the 605 type coverstitch in a well known manner although two needles 3 and a single thread 16 for each is shown for clarity those skilled in the art are aware that multiple threads from multiple spools are conventionally used and each needle there may be more than two industrial machines is supplied with thread from its respective spool a puller roller 4 is driven by drive unit 5 which may for example be a standard electric motor variable speed drive unit referring briefly to fig2 a typical coverstitched hem is shown the fabric part 2 has been hemmed as shown by the double layer and folded over to illustrate the visible top portion 11 of the coverstitch and the 34 blind 34 or bottom portion 11 39 of the coverstitch in one illustration of the practice of the invention the roller 4 is in frictional engagement with fabric 2 and works in conjunction with conventional feed dogs 8 of the sewing machine 1 to advance the fabric to the left as shown by the arrow in fig1 an edge sensor 6 which may be optical i e infra red visible light laser or other detects the presence or absence of fabric leaving the needles 3 in the interval between successive fabric parts the.