What should I do if the thread tension is too tight on my sewing machine?
If the upper tension is too tight, loops will appear on the surface of the fabric. Reduce the tension by turning the upper tension-control dial to a lower number. If the bobbin thread was incorrectly threaded, the upper thread may appear too tight, so you should also rethread the bobbin thread. (Page 1)
From the official Brother XH2177-001 Computerized Sewing Machine manual, page 1
Have a follow-up question?
Answers from the official manual.
Common questions