JUKI МН-481 - Page 38

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Troubles Causes Corrective measures
5
Set position of the frame thread eyelet
is not suitable.
™
Try to lower the position.
Refer to “25. POSITION OF THE FRAME
THREAD EYELET”.
6
Position of the thread take-up lever is
not suitable.
™
Try to push it up.
Refer to “24. POSITION OF THE THREAD
TAKE-UP LEVER”.
7
Throat plate does not fi t.
™
Replace it with other throat plate which has
larger needle hole.
4. Needle breakage
1
Needle is bent.
™
Replace it with a straight needle.
Refer to “6. ATTACHING THE NEEDLE”.
2
The timing of the needle motion with
that of needle is not correct.
™
Adjust the timing.
Refer to “17. ADJUSTING THE FEED TIM-
ING”.
3
Position of the presser foot is wrong.
™
See if the hole of presser foot, hole of throat
plate and loop guide plate are placed in the
center of needle.
4
Motion of the needle guard is not ad-
equate.
™
Check the position and timing of the motion of
the needle guard.
Refer to “22. MATCHING THE MOTION OF
THE NEEDLE GUARDS WITH THE LOOP
GUIDE”.
5
The tension of needle thread is too
high.
™
Loosen the tension.
Refer to “9. THREAD TENSION”.
6
Thickness of the needle is not suitable.
™
Replace it with a suitable needle in accordance
with the quality and weight of the sewing ma-
terial.
Refer to “6. ATTACHING THE NEEDLE”.
5. Puckering
1
Thread tension is too high.
™
Reduce the thread tension, especially the
looper thread.
Refer to “9. THREAD TENSION”.
2
Timing of the looper thread take-up is
wrong.
™
Set the timing to a little earlier.
Refer to “23. POSITIONING THE LOOPER
THREAD TAKE-UP”.
3
Thread paths are not smooth.
™
Polish the thread path with lapping agent on
thick thread #8.
4
Pressing force of the presser foot is too
much
™
Tighten the adjusting screw.
Refer to “12. ADJUSTING THE PRESSER
FOOT”.
5
Needle
™
Use a fi ner needle.
6
Throat plate.
™
Use a throat plate designed for fi ne materials.
™
Ratio of differential feed; Apply 1:0.7 ratio for
gathering.
6. Puckering
1
Presser foot
™
Use a sliding type presser foot.
Refer to “12. ADJUSTING THE PRESSER
FOOT”.
2
Pressure of presser foot
™
Reduce the pressure.
Refer to “12. ADJUSTING THE PRESSER
FOOT”.