DURKOPP ADLER 559 Operating, Installation And Servicing Instructions page 67

Description of fault
Skipped stitches
Thread breakage
Possible cause
The material is not spread or
spread too little.
The matching needle size has
to be chosen according to the
material, the material thickness
and the thread used.
Throat plate, hooks or
spreaders have possibly been
damaged by the needle.
Possibly parts have been
inserted which do not match the
sewing equipment, as e.g.
throat plate, hook, spreader,
clamping plates, upper/lower
fabric clamps.
When converting the seam
width the looping stroke has not
been readjusted.
Hook or spreader are adjusted
wrongly.
Even if no wrong adjustment is
to be seen and the
above-mentioned measures did
not lead to an improvement,
check the opposite points once
again.
Needle and hook thread are
threaded incorrectly.
The needle is bent,
sharp-edged or incorrectly
inserted in the needle bar.
The thread used is knotty, hard
or too thick and thus unsuitable.
The thread tensions are too
tight for the thread used.
Error elimination
Check the spreading
(see chapter "Spreading").
Change the needle size.
(See Operating Instructions)
Attention!
After changing the needle size the
distance needle-hook has to be
checked.
Have the parts reworked by the
service personnel.
Check the sewing equipment parts
according to the equipment sheet.
Adjust the looping stroke
(see chapter "Looping stroke").
Check the adjustments described
in the following chapters of the
Service Instructions:
"Adjusting the locking positions"
"Adjusting the looping stroke"
"Needle bar height"
"Distance between hook and
needle"
"Needle protection"
"Spreader"
"Spreader plate"
"Throat plate"
"Rotary thread take-up disc"
Check threading of needle and hook
thread (see Operating Instructions
"Thread the needle thread"/ "Thread
the hook thread").
Insert a new needle. Insert the
needle in the needle bar correctly.
Use recommended threads only
(see Operating Instructions:
Needles, threads and gimps).
Check the thread tensions
(see Operating Instructions "Thread
tensions")
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