Operation Manual

Malfunction Remedy
5. Unequal stitch lengths or
stitch positions.
a) V-belt is too loose.
b) Gimp is too taut, jams or does
not pass easily through the
gimp hole of the needle plate .
Tension V-belt as per Installation Instructions for
the 558.
Use thinner gimp or insert a needle plate with
larger gimp hole.
For stiff and inflexible gimps use gimp roller holder
on the table (Order no. 557 1103).
6. Missing stitches
a) Needle is blunt, bent or not
correctly inserted.
b) Upper or underthread is
not correctly threaded.
c) Thread tension is set
too taut.
d) Thread unwinds badly from
the thread rolls.
e) Hook or spreader have
become misadjusted.
f) Material is not held or spread
correctly.
Insert a new, flawless needle (see Chapter 2.4).
Check the threading path of the upper or
underthread (see Chapter 2.5 and 2.7).
Reset thread tension (see Chapter 2.8).
See Chapter 2.7.
Readjustment only through a specialist !
Check the spreading of the material (see Chapter
2.17) and pressure of the upper cloth clamps.
7. Loose stitches.
a) Thread tensions are not set
correctly.
b) Upper or underthread is not
threaded correctly.
Reset thread tensions (see Chapter 2.8).
Check the threading path of the upper or
underthread (see Chapter 2.5 and 2.7).
8. Thread breakage.
a) Upper or underthread is not
threaded correctly.
b) Needle is incorrectly inserted,
bent or sharp-edged.
c) Thread used is unsuitable
(knotted, hard or too thick).
d) Thread tensions are set too
taut.
e) Needle plate, hook or
spreader are damaged.
Check the threading path of the upper or
underthread (see Chapter 2.5 and 2.7).
Insert a new, flawless needle (see Chapter 2.4).
Use a different thread. See recommendations in
Chapter 2.6.
Reset thread tensions. (see Chapter 2.8)
Replace damaged parts through new ones or
have reworked by a specialist.
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