Owner's Manual

T-8420B, 8450B, 8720B, 8750B

7. THREAD TENSION

7- 1. Adjusting the thread tension

Good even stitches

Upper thread

Lower thread

Upper thread tension too weak or

lower thread tension too strong

Increase the upper thread tension.

Decrease the lower thread tension.

Upper thread tension too strong

or lower thread tension too weak

Decrease the upper thread tension.

Increase the lower thread tension.

CAUTION

Turn off the power switch before adjusting the

lower thread tension. The motor will keep turning

even after the power is switched off as a result of

the motor’s inertia. Wait until the motor stops fully

before starting work.

The machine may operate if the treadle is

depressed by mistake, which could result in injury.

Turn the adjusting screw (1) to adjust.

After the lower thread tension has been adjusted, adjust the

upper thread tension so that a good, even stitch is obtained.

1. Lower the presser foot.

2. Adjust by turning the tension nut (2).

0572M

0573M

0574M

2990M

2923M

Becomes stronger

Becomes weaker

Becomes stronger

Becomes weaker

2924M

Becomes weaker

Becomes stronger