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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
5-8) Single chain thread cast-
off (Right, Middle, Left)
8-A) Needle
A-1) Needle bend, improper needle attach-
ing and wrong needle
Replace the needle with the new one,
Use UY128GAS.
8-B) Needle height
B-1) Needle bar position is too high.
Refer to the standard adjustment figures.
8-C) Threading
C-1) Incorrect threading
Refer to threading diagram.
8-D) Throat plate
D-1) R of stitch tongue in throat plate is too
small.
Incorrect polishing
Increase R.
Polish correctly.
8-E) Looper
E-1) R of looper’s ventral section is too
large and ridge line is not tense, for
which needle thread is likely to slip
from looper.
Replace it with the genuine part.
8-F) Looper adjustment
F-1) Too little contact amount between loop-
er’s back and needle
Refer to the standard adjustment figures.
8-G) Thread tension
G-1) Thread tension is too weak.
Increase tension.
8-H) Needle thread guide rod
H-1) Low position of thread guard results in
too large needle thread loop.
Lift thread guide position.
8-I)
Thread guard position
I-1) Thread guard position is too high.
Refer to the standard adjustment figures.
8-J) Auxiliary thread tension
J-1) Use of nipper could easily generate
this trouble.
Do not use nipper.
8-K) Looper thread cam
thread guide position
K-1) Drawing-in amount of looper thread is
too much.
Decrease drawing-in amount of thread.
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