bobbin issues
 

I do longarm quilting and the other day my tension screw fell out on my bobbin winder so I put it back on I just got the tension way too tight and thought it was okay but when sewing the thread kept breaking and I was really frustrating but got the quilt done. My husband checked out the bobbin winder and loosened up the tension it worked great hope that will take care of the problem. I changed needles, loosened up top tension nothing seemed to help so got out older bobbin that was already wound and it worked wonderful.

How a bobbin is wound does affect the stitching a lot. With the tension too tight, my bet is that the thread stretched as it was loading onto the bobbin. When you went to sew with it, the thread was already stretched so much it had no "give" left for the stitching action.

Sloppily-wound bobbins typically have a different problem -- you get bird's nests underneath! You might want to try out the new bobbin on a test piece to make sure the tension on the bobbin winder is correct now.