– 193 –
Trouble Cause (1) Cause (2) Check and corrective measures
8. Thread cast-off from the needle at 8-1) Wrong wiper position Adjust the wiper position. (Refer to wiper adjustment.)
the sewing start
8-2) Defective needle thread clamp Position adjustment of the needle thread trimming
unit (Refer to adjustment of the needle thread
trimming unit.)
8-3) Defective bobbin thread clamp Position adjustment of the bobbin thread trimming unit
(Refer to adjustment of thr bobbin thread trimming
unit
9. Stitch skipping at the sewing start 9-1) Deficient bobbin thread 1-A)Bobbin idling Increase the bobbin thread tension.
Put a cloth under the bobbin to prevent it from idling.
1-B)Wrong wiper position Adjust the wiper position. (Refer to wiper adjustment.)
10.Broken material in the garment 10-1)Dull center knife 1-A)Defective center knife Replace the center knife with new one.
body or welting patch (entirely)
1-B)Defective installation of Install the center knife properly,
center knife (Refer to adjustment of the center knife.)
10-2)Too thick needle, or blunt tip Use a thinner needle. Replace the needle with new
of the needle one.
11. Needle thread untrimmed 11-1)Malfunction of the needle 1-A)Defective installation of the Install the needle thread trimmer properly.
thread trimmer needle thread trimmer (Refer to adjustment of the needle thread trimmer unit.)
1-B)Malfunction of the thread Reduce the air pressure of the cylinder to approx.
trimming cylinder 1.8 kg and check the cylinder operation. If the cylin-
der does not operate well, replace the cylinder
with new one.
12. Bobbin thread untrimmed 12-1)Defective bobbin thread 1-A)Deficient pressure of the Increase the spring pressure.
trimmer bobbin thread trimmer spring
1-B)Dull bobbin thread trimmer Replace the trimmer with new one.
12-2)Malfunction of the bobbin Check the drain in the cylinder or replace the cylinder
thread trimming cylinder with new one.
To Next Page
Loading...
Need help?
General
