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2-5) Height of the needle bar is not correct.
5-A) Height of the needle bar is not adjusted
Re-adjust the height of the needle bar.
to the specified dimension.
2-6) Defective presser foot
6-A) The presser foot fails to rest on the throat plate.
Height of the presser foot is incorrect.
2-7) Improper feed timing (bent needle).
Re-adjust the feed timing.
2-8) Thread take-up spring has been improperly .
8-A) Stroke of the thread take-up spring is
Decrease the tension of the spring.
adjusted
too high.
8-B) The thread take-up spring is too tense.
Decrease the tension of the spring.
2-9) Incorrect needle entry
9-A) The needle comes in contact with the
Adjust the needle entry.
needle hole in the throat plate.
2-10) Improper pressure of the presser foot
10-A) Pressure of the presser foot is too low.
Increase the pressure of the presser foot.
3. Needle Thread Breakage
3-1) Thread path is incorrect.
1-A) Thread path is not smooth on the surface.
Smoothen the thread path.
The needle thread splits
finely or breaks during sewing.
1-B) Thread path has scratches on the surface.
Smoothen the thread path.
1-C) Thread is caught in some part of the thread path.
Smoothen the thread path.
3-2) Improper needle thread tension
2-A) Needle thread tension is too high or too low.
Adjust the needle thread tension.
2-B) The tension controlled by the tension
Adjust the tension controller No. 1 thread tension
controller No. 1 is too low.
to prevent the thread from flapping.
3-3
Defective needle
3-A) Bent needle
Replace the needle with a new one.
3-B) The needle has scratches.
Replace the needle with a new one.
3-C) Tip of the needle is blunt.
Replace the needle with a new one.
3-D) The needle is installed facing the wrong
Re-install the needle in the correct manner.
direction.
3-E) The needle is too thick or too thin for the
Replace the needle with a new one.
thread used.
Trouble
Cause (1)
Cause (2)
Check Procedure and Corrective Measures
Thread
Needle
Stitch
Throat Plate
Thread Breakage
Continued from the previous page
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Cloth