JUKI LK-1903A-305 Instruction Manual page 59

Trouble
6. The needle thread 1 The needle thread tenson s not
comes out on the
wrong sde of the 2 The tenson release mechansm
materal.
3 The needle thread after thread
4 Number of sttches s too few.
5 When sewng length s short (End
6 Number of sttches s too few.
7. T h r e a d s b r e a k 1 Th e m ov n g k nfe h a s b e e n
at tme of thread
trmmng.
8. The thread clamp 1 The needle thread at the sewng
s entangled wth
needle thread.
9. Uneven length of 1 The tenson of thread take-up
the needle thread
0. T h e l e n g t h o f 1 The tenson of thread tenson
needle thread does
not become short. 2 The tenson of thread take-up
3 The tenson of thread take-up
. T h e k n o t t  n g 1 Idlng of bobbn s large.
secton of bobbn 2 The bobbn thread tenson s too
thread at 2nd sttch
at the sewng start 3 The needle thread tenson at st
a p p e a r s o n t h e
rght sde.
Cause
hgh enough.
fals to work properly.
trmmng s too long.
of needle thread protrudes on the
wrong sde of sewng product.)
mproperly poston.
start s too long.
sprng s too low.
controller No.  s too low.
sprng s too hgh.
sprng s too low and moton s
unstable.
low.
sttch s too hgh.
－
Correctve measures
™ Increase the needle thread tenson.
™ Check whether or not the tenson dsc
No. 2 s released durng bar-trackng.
™ Increase the tenson of the thread
tenson controller No. .
™ Correct the poston of the movng knfe.
™ Turn OFF the thread clamp.
™ Turn OFF the thread clamp.
™ Use the lower plate, the hole of whch
s larger than the presser.
™ Correct the poston of the movng knfe.
™ Tghten thread tenson controller No. 
and make the length of needle thread
33 to 36 mm.
™ Increase the tenson of the thread take-
up sprng.
™ Increase the tenson of thread tenson
controller No. .
™ Decrease the tenson of thread take-up
sprng.
™ Increase the tenson of thread take-up
sprng and lengthen the stroke as well.
™ Adjust the poston of the movng knfe.
™ Increase the bobbn thread tenson.
™ Decrease the needle thread tenson at
st sttch.
™ Turn OFF the thread clamp.
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