Mistakes & fixes

Loose loops hanging off a serged edge, or an edge that curls and puckers, points to the tension dials being out of balance for the thread and fabric. Adjust one dial at a time on a scrap.

The bobbin thread breaking mid-seam, leaving only top stitches, often means the bobbin was wound unevenly, inserted backward, or lint has jammed the case. Rewind the bobbin evenly, reinsert correctly, and clean the case.