Innov-is BP3500D
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FAQs & Troubleshooting |
Upper thread tightened up
Symptom
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(1) Lower side of fabric (2) Lower thread visible from upper side of fabric (3) Upper thread (4) Upper side of fabric (5) Lower thread |
Cause
If the lower thread is incorrectly threaded, instead of the appropriate tension being applied to the lower thread, it is pulled through the fabric when the upper thread is pulled up. For this reason, the thread is visible from the upper side of the fabric.
Remedy/check details
Correctly install the lower thread according to the following procedure.
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(1) Bobbin cover
(2) Latch |
Remove the bobbin from the bobbin case.
If the bobbin is inserted with the thread unwinding in the wrong direction, sewing will be done with an incorrect thread tension.
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(1) Tab |
Be sure to hold down the bobbin with your finger and unwind the bobbin thread correctly, otherwise the thread may break or the thread tension will be incorrect.
If the thread is not correctly inserted through the tension-adjusting spring of the bobbin case, it may cause incorrect thread tension.
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(1) Tension-adjusting spring |