Pfaff 1540 User Manual
Page 70

68
37. Adjustment of needle thread tension
Requirement:
Within the adjusting range from 3 to 5, the interlacing of needle thread and bobbin thread (cotton thread
50/2 or synthetic fiber thread 100/35) must take place approximately in the middle of the fabric (fig. 74).
Check:
z
Set needle thread tension to "5".
z
Press the button for the widest zigzag stitch.
z
Set stitch length to "2.0".
z
Place a piece of fabric under the zigzag foot and sew.
z
Press the button for straight stitch.
z
Set stitch length to "2.5".
z
Sew with straight stitch.
Adjustment:
z
First turn knurled nut 125 fully to the left (fig. 76).
z
Press the button for the widest zigzag stitch.
z
Set stitch length to "2.0".
z
Sew with zigzag stitch.
z
At the same time turn the knurled nut gradually in clockwise direction, until the interlacing is in the cen-
ter of the fabric (fig. 75).
Cross-check:
z
Sew with straight stitch and zigzag stitch as described under "Check".