A tiny "lint glob" in the bobbin case can cause random loops as it will cause the bobbin thread to "stick" (be tighter) every once in a while. If you are positive that your case is clean (Don't forget to run a business card under the bobbin tension clasp to remove any tiny hiding globs), then I suggest that your top tension needs to be tightened just a tad bit.... Try this and see if it helps!!!
loops on bottom of quilt
in Ask The Expert - Thread, Needle, Bobbins
Posted
A tiny "lint glob" in the bobbin case can cause random loops as it will cause the bobbin thread to "stick" (be tighter) every once in a while. If you are positive that your case is clean (Don't forget to run a business card under the bobbin tension clasp to remove any tiny hiding globs), then I suggest that your top tension needs to be tightened just a tad bit.... Try this and see if it helps!!!