Duerkopp Adler 558 Operating Instructions Manual page 76

Malfunction
9. Needle breakage.
a) Needle thickness is unsuitable
for the material or the thread.
b) Needle is hitting the cloth
clamps.
10. No clean seam beginning or
unthreading of the upper
thread.
a) Rest tension for the upper
thread is set too taut. Start
thread for the next sewing
beginning is thus too short.
b) Thread gripper on the upper
thread tension does not
clamp the upper thread in
the machine end position.
78
Remedy
Use a needle thickness as per Chapter 2.6 or as
per sewing device (E no.).
The max. buttonhole width listed in the table on
page 8 for each sewing device (E no.) may not be
exceeded. Resetting by service personnel as per
Service Instructions for the 558.
Reset the rest tension for the upper thread (see
Chapter 2.8).
Reset the thread gripper as per Service
Instructions for the 558.