Singer S900 INSPIRATION Instruction Manual 2 - Page 10

ADJUSTING THE TENSIONS Always adjust the upper tension with the presser foot down, as the tension is released when it is raised. To increase the tension on the upper thread, turn dial (Fig. 13) to the right. To decrease, turn to the left. Before adjusting lower tension be sure that the machine is threaded properly. When it is necessary to change the bobbin tension, turn the small screw (Fig.15) on side of the bobbin case clockwise to tighten, counter clockwise to loosen. Fig. 13 Fig. 14-A Fig. 14-B When the upper tensions are properly balanced, a perfect stitch will be formed with both threads inter locking in fabric (Fig. 14-A). When the upper tension is too tight, the lower thread is pulled up over the upper thread which is lying flat on the fabric (Fig. 14-B). When the upper tension is too loose, the upper thread forms loops over the lower thread lying flat on the fabric (Fig. 14-C). Fig. 14-C Fig. 15