Pfaff 1571 Instruction Manual page 116

Comments
Comments
Various improvements have been made to the machines of the series 570 / 590; 1570 / 1590
with thread trimmer –900/81:
1. For a better sewing start after the thread has been trimmed, following parts were
2. Adjustment modification due to the new parts
3 . For a better error analysis a check list was developed for a simple correction of the
2
modified or added as new parts:
a thinner thread lubricating felt (6 mm thick) to reduce the primary thread tension,
Part-No. 91-165 384-05,
a weaker spring for the primary thread tension to reduce the primary tension,
Part-No. 91-263 391-05
a new bobbin case with reversing cam, Part No. 91-263 378-91
a new needle holder for 2-needle machines,
Part No. 91-164 726-93/001 (diagonal needle gauge 2.4 mm)
Part No. 91-164 726-93/002 (diagonal needle gauge 2.8 mm)
Part No. 91-164 726-93/003 (diagonal needle gauge 3.2 mm)
(see Chapter "Adjustment")
problems (see Chapter "Check List")