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WARNING :
Turn OFF the power before starting the work so as to prevent accidents caused by abrupt start of the sewing machine
Trouble (1)
Trouble (2)
Cause (1)
Cause (2)
Check and corrective measures
5. Stitch skipping
5-1) Looper does not scoop
the right needle thread.
1-A) Looper
A-1) Incorrect shape of pointed end of loop-
er disables scooping a loop.
Replace it with the genuine part.
Without thread
trimming
1-B) Needle
B-1) Needle bend, incorrect needle mount-
ing direction, wrong needle
Replace the needle with new one. Cor-
rect the mounting direction.
Use UY128GAS.
1-C) Auxiliary thread tension
C-1) Not used.
Use nipper.
1-D) Needle thread guide rod
D-1) Height is too high.
Correct the height to appropriate height.
1-E) Needle height
E-1) Needle bar position is too high.
Refer to the standard adjustment figures.
1-F) Threading
F-1) Incorrect threading
Refer to threading diagram.
1-G) Needle thread guard
G-1) Not used.
Use needle guard.
1-H) Spreader
H-1) Spreader thread tension is too strong.
Reduce the tension.
1-I)
Needle heat
I-1) Stitch skip occurs before thread break-
age produced by needle heat.
Same described in page " Thread break-
age by needle heat"
1-J) Looper adjustment
J-1) Incorrect clearance adjustment, incor-
rect returning amount adjustment
Refer to standard adjustment.
1-K) Needle guard, front and
rear
K-1) Incorrect contact amount, incorrect
height
Refer to the standard adjustment figures.
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