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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
14-D) Top covering thread
take-up
D-1) Drawing-in amount of top covering
thread is too much or too little.
Refer to the standard adjustment figures.
14-E) Needle thread tension
E-1) Needle thread tension is too weak.
Increase tension.
14-F) Threading
F-1) Incorrect threading
Refer to threading diagram.
14-G) Top covering thread ten-
sion
G-1) 1st thread tension is too weak.
Increase tension.
14-H) Stitch tongue of presser
foot
H-1) Thread threading is not smooth due to
incorrect shape of stitch tongue.
Replace when its shape is modified or
changed too much.
14-I) Needle
I-1) Worn out needle point, needle bend,
wrong needle
Replace needle with new one.
Use UY128GAS.
14-J) Feed dog
J-1) Flaw, surface in feed dog
Modify or replace
6. Stitch of ravel-
ing prevention
is not possible.
6-1) Adjustment of thread
hook and needle
1-A) Thread hook does not
hook needle thread
because of incorrect ad-
justment of thread hook
and needle.
Refer to "12.-(10) Adjusting the thread
hook".
6-2) Parameter settings
2-A) Incorrect settings
Refer to "12.-(9) Setting the raveling
prevention parameter".
