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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 to 36mm
Increase the sewing length to more than 10mm.
Trouble
Cause (1)
Cause (2)
Check and corrective measures