21
Thread tension adjustment
1. Correct tension
2. Unbalanced lower looper thread wraps
around the back.
Tighten the thread tension of the lower
looper (Dial 4) or loosen the needle thread
tension (Dial 2).
3. Needle thread unbalanced and too loose.
Tighten the needle thread tension (Dial 2)
or loosen the tension of lower looper thread
(Dial 4).
Top side
Top side
Top side
Underside
Underside
Underside