Why does my sewing machine keep jamming underneath?
However certain you are that the problem with the machine is most likely due to a huge tangled mess of thread in the bobbin underneath the fabric, the most common reason for the jamming is usually the lack of sufficient tension in the upper thread.
Why does my bobbin thread keep jamming singer?
This can be caused if the top thread tension is too tight, or if the bobbin thread is not in the bobbin case tension. … Make sure the bobbin is correctly seated in the bobbin case (bobbin holder), and check that the upper thread tension is not set too tightly.
Why is my thread bunching up?
What should I do if I experience thread bunching? As “thread bunching” occurs on the underside of the fabric, some people think it is due to the lower thread. They check whether the bobbin is sitting correctly in the bobbin case or even replace the bobbin. … On many models, the upper thread tension is set automatically.