Testing the stitch width: 1. Cut two pieces of fabric measuring 3X12 inches (7.5x30cm). Divide one piece of fabric into thirds, and place it on top of the other. Number each third to correspond with the numbers on the cutting dial. Set your machine for a 2.5mm stitch length, 1.5-2mm stitch width, and a balanced 4-thread stitch. 2. Adjust the cutting width to 1mm, and stitch through both layers of fabric until you reach the first line. Turn the cutting width dial to 2mm, and stitch to the next line. Turn the dial to 3mm, and stitch to the next line. Turn the dial to 3mm and serge off the fabric. 3. Look for the best section of stitching on the fabric. If the stitch needs more or less fabric to create a good seam, then fine-tune both looper tensions so that you end up with a well-balanced seam. Testing the stitch length: 1. Cut two pices of fabric measuring 3X12 inches (7.5X30cm). Divide one piece of fabric into quarters, and place it on top of the other. Number each section. Set your machine for a 1mm stitch length, 1.5 to 2mm cutting width, and a balanced 4-thread stitch. 2. Serge to the first line. Change to a 2mm stitch length and stitch to the next line. Continue until you have serged off the fabric. 3. Examine your sample, and review the fabric and stitch adjustments required for your project. If the cutting width is adequate, then you need to fine-tune the looper tensions.Griffin, Mary is the author of 'Serger Secrets' with ISBN 9781579544645 and ISBN 1579544649.