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8. Defective stitches with the synthetic
8-1) Thread breakage due to heat
1-A) The sewing speed is too fast.
Slow down the maximum speed.
thread
1-B) The needle used is too thick.
Use a thin needle or a super needle for the synthetic
thread.
Use silicon.
Use a needle cooler.
8-2) Thread makes burrs.
2-A) Thread path is defective.
Polish the thread path of each component with polishing powder.
2-B) Finish of the needle hole is defective.
Replace the needle.
2-C) Loop of the needle thread falls down.
Move the machine arm thread guide A to the left.
8-3) Thread floating occurs at the
3-A) Penetration registance of the
Use a thinner needle. (Lower the number of needle to be used.)
sewing start.
thread against the cloth is too
small.
Needle thread clamp device ON.
8-4) Stitch skipping due to the heat.
4-A) Sewing speed is too fast.
Change the maximum speed (electrical components.)
4-B) Needle is too thin.
Use a thicker needle. (Raise the number of needle to be used.)
4-C) Loop of the needle thread falls down.
Attach the needle with the long groove orienting slightly
to the right (approximately 20
°
).
8-5) Uneven stitch tightness due
5-A) Sewing speed is too fast.
Reduce the speed by means of the speed variable resistor.
to the stretch of thread.
5-B) Tension of the tension controller
Decrease the tension of tension controller AT.
AT is excessive.
9. Thread chips generated in the
9-1) Long needle thread at the
1-A) The thread trimmer is used
Needle thread clamp device OFF
shuttle
beginning of stitches
for cutting.
Adjust the needle thread length to 32 ~ 36mm
Increase the sewing length to more than 10mm.
Trouble
Cause (1)
Cause (2)
Check and corrective measures