You should see a small screw on the flat/closed side of the bobbin case. Turning the screw a tiny bit counterclockwise will loosen the bobbin tension; turning it clockwise will tighten the tension.
Probable Causes: – Top or bobbin thread is not set correctly. – Check the bobbin was inserted properly. …
If your thread is pulled tight on the underside and not forming an even stitch then (counter-intuitively) it’s usually the top thread tension that’s wrong. Sometimes very lightweight fabrics such as sheers can get dragged down into the machine so it’s a good idea to use a straight stitch plate.
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.
What tightens or loosens the flow of the thread?
You’ve probably noticed the tension regulator on your sewing machine. It’s usually a dial with the numbers 3, 4, and 5 highlighted or circled. This regulator tightens, or loosens, the tension discs that the thread passes down through before it goes up and through the looper.
How do I stop loose threads?
Tie off the loose threads to prevent unraveling. You will need to tie the threads off to prevent further unraveling. At each end of the opening, you should have two threads, four in all. At one end of the ripped seam, tie these two threads together snugly against the edge of the seam.