Operation Manual

Operating Instructions 650-10 - 02.0 - 10/2015144
Missing
stitches
• The needle and hook
threads are not threaded
correctly
• Check threading path
(
Operating Instruc-
tions, Operation)
• Needle is blunt or bent
• Needle is not inserted
correctly into the needle
bar
• Replace the needle
• Insert the needle into the
needle bar
• The needle thickness
used is unsuitable
• Use recommended nee-
dle thickness ( S. 147)
• The thread reel holder is
installed incorrectly
• Check thread reel holder
(
Operating Instruc-
tions, Operation)
• Thread tensions are too
tight
• Check thread tensions
(
Operating Instruc-
tions, Operation)
• Sewing material is not
held correctly
• Check clamping pressure
( Service Instructions)
• The loop stroke was not
corrected when changing
the zigzag stitch width
• Adjust the loop stroke
(
Service Instructions)
• Incorrect parts used for
the desired sewing
equipment
• Check the parts based
on the equipment sheet
• Throat plate, hook or
spread have been dam
-
aged by the needle
• Have parts reworked by
qualified specialists
Meaning Possible causes Remedial action