DURKOPP ADLER 969 Classic, Service Instructions Manual

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Troubleshooting
Service Instructions 969 - 06.0 - 03/2019 113
19.3 Errors in sewing process
Error Possible causes Remedial action
Unthreading at seam
beginning Needle thread tension is too
firm Check needle thread tension
Thread breaking Needle thread and hook
thread have not been
threaded correctly Check threading path
Needle is bent or sharp-edged Replace needle
Needle is not inserted
correctly into the needle bar Insert the needle correctly into the
needle bar
The thread used is unsuitable Use recommended thread
Thread tensions are too tight
for the thread used Check thread tensions
Thread-guiding parts, such as
thread tube, thread guide or
thread take-up disk, are
sharp-edged Check threading path
Throat plate, hook or spread
have been damaged by the
needle Have parts reworked by qualified
specialists
Missing stitches Needle thread and hook
thread have not been
threaded correctly Check threading path
Needle is blunt or bent Replace needle
Needle is not inserted
correctly into the needle bar Insert the needle correctly into the
needle bar
The needle thickness used is
unsuitable Use recommended needle
thickness
The reel stand is assembled
incorrectly Check the assembly of the reel
stand
Thread tensions are too tight Check thread tensions
Throat plate, hook or spread
have been damaged by the
needle Have parts reworked by qualified
specialists