SunStar SC-7007S, Руководство пользователя

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Cause of troubles and troubleshooting
1) Sewing machine troubleshooting
No Symptom Checkpoints Root cause Corrective action
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2
Needle breaks
Direction and height of needle
Needle
Ascending level of needle bar
Height of needle
Gap between the needle and the looper
Threading method
Needle
Direction and height of needle
Upper thread tension
Working capacity of take-up lever spring
Direction and height of needle
Needle
Threading
Ascending level of needle bar
Height of needle bar
Gap between the needle and the looper
Needle is inserted into wrong position.
Needle is bent.
Bad timing of feed dog.
The timing of the needle and the looper is bad.
The timing of the needle and the looper is bad.
The timing of the needle and the looper is bad.
Wrong threading.
Bent needle or broken needle tip.
Needle inserted in the wrong position.
Too tight upper thread tension.
Loose upper thread.
Needle inserted in the wrong position.
Bent needle or broken needle tip.
Thread passing at wrong position.
The timing of the needle and the looper is bad.
The timing of the needle and the looper is bad.
The timing of the needle and the looper is bad.
Remaining length of upper thread is short .
Reinsert the needle correctly.
Change the needle.
Adjust the timing of feed dog.
Adjust the timing between the needle and the looper.
Adjust the timing between the needle and the looper.
Adjust the timing between the needle and the looper.
Thread the needle correctly.
Change the needle.
Insert the needle correctlyz.
Reduce tension of upper thread.
Adjust take-up lever spring.
Reinsert the needle in the right direction.
Change the needle.
Change the needle.
Adjust the timing between the needle and the looper.
Adjust the timing between the needle and the looper.
Adjust the timing between the needle and the looper.
Adjust the thread adjusting device.
Thread breaks
3 Stitch skips
Too strong upper thread tension.
Too thick a needle for thread.
Take-up lever pulls out the upper
thread because the needle up and
down position is too high.
Check the Up-stop
position of needle
Adjust tension of upper thread.
Check thickness of needle.
Adjust the up-stop position of
needle.
5
Upper thread
is pulled out
when sewing
commences.
Too tight upper thread tension.
Too loose lower thread tension.
Reduce tension of upper thread.
Increase tension of lower thread.
Upper thread
does not sink.
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