Is it the upper thread that is looping under the fabric? If so, that's what is called thread nesting or bird nesting. It is usually caused by it not being threaded correctly or the tension is off. Most likely, it is because the thread is either not in all the guides, the thread path is incorrect (it may have jumped out of the take-up lever), OR (most frequently) the thread is not completely seated in the tension disk.
#1--install a brand new needle that is compatible with the thread & fabric you are sewing. All About Needles
#2--remove the upper thread. Always raise the presser foot and rethread from the beginning making sure to follow all the guides and the thread pathway.
Set the upper tension to the midway point between high & low number and test. Re-adjust tension as needed. If the upper thread is showing too much on the underside of the fabric, the upper tension is too loose. If bobbin thread is showing on the top, then upper tension is too tight. Correct tension is when both upper & bobbin threads meet in the middle.
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Is it the upper thread that is looping under the fabric? If so, that's what is called thread nesting or bird nesting. It is usually caused by it not being threaded correctly or the tension is off. Most likely, it is because the thread is either not in all the guides, the thread path is incorrect (it may have jumped out of the take-up lever), OR (most frequently) the thread is not completely seated in the tension disk.
#1--install a brand new needle that is compatible with the thread & fabric you are sewing. All About Needles
#2--remove the upper thread. Always raise the presser foot and rethread from the beginning making sure to follow all the guides and the thread pathway.
Set the upper tension to the midway point between high & low number and test. Re-adjust tension as needed. If the upper thread is showing too much on the underside of the fabric, the upper tension is too loose. If bobbin thread is showing on the top, then upper tension is too tight. Correct tension is when both upper & bobbin threads meet in the middle.
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