Thread Tensions; Upper Thread Tension; Lower Thread Tension - Brother 681B-UG User Manual

THREAD TENSIONS

It is important that tension of upper and lower threads be equal to prevent puckering of
material or other problems.
It is recommended that a test sample be made before starting to sew.

UPPER THREAD TENSION

LOWER THREAD TENSION

To regulate upper thread tension, merely
turn thread tension dial with your thumb
after lowering the presser foot.
THE HIGHER THE NUMBER, THE
TIGHTER THE TENSION.
To increase tension: Turn dial to right to
To decrease tension: Turn dial to left to
NOTE: The zigzag stitch requires less upper
tension than the straight stitch.
Although lower thread tension has already
been adjusted at the factory, when sewing
very thin or heavy materials it may have to
be readjusted.
To regulate the lower thread tension, turn
small screw on the tension, spring of the
bobbin case with the small screw driver.
To increase tension: Turn the small screw
To decrease tension: Turn
-15-
larger number.
smaller number.
clockwise very
slightly.
the screw
counterclockwise
very slightly.