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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
From the previous page
5-9) Double bonding stitch
(Middle, Left)
9-A) Throat plate
A-1) R of stitch tongue in throat plate is too
large. Stitch tongue is too short.
Replace it with the genuine part.
9-B) Needle
B-1) Worn out needle point, needle bend,
wrong needle
Replace needle with new one.
Use UY128GAS.
9-C) Looper
C-1) Flaw in looper’s ventral section, incor-
rect polishing
Replace the looper when modified or its
shape is changed too much.
9-D) Needle height
D-1) Needle bar position is too low.
Refer to the standard adjustment figures.
9-E) Threading
E-1) Incorrect threading
Refer to threading diagram.
9-F) Needle thread tension
F-1) Tension is too weak.
Increase tension.
9-G) Needle thread guide rod
G-1) Substandard lower positioning of
thread guide
Adjust the thread guide position upward.
9-H) Auxiliary thread tension
H-1) Use nipper is likely to generate this
trouble.
Do not use nipper.
5-10) Irregular stitches
(Left, Middle, Right)
10-A) Throat plate
A-1) Incorrect polishing
Polish correctly.
10-B) Spreader adjustment
B-1) Stroke of spreader is too large.
Refer to the standard adjustment figures.
10-C) Looper
C-1) Worn out looper’s pointed end and
incorrect polishing
Replace the looper when modified or its
is shape changed too much.
10-D) Top covering thread
take-up
D-1) Drawing-in amount of top covering
thread is too much.
Refer to the standard adjustment figures.
10-E) Needle thread tension
E-1) Needle thread tension is too weak.
Increase tension.
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