SINGER 1120 - Manual (Page 18)

Upper thread tension
Please note:
Basic thread tension setting: "4"
To increase the tension, turn the dial to the next number up. To
reduce the tension, turn the dial to the next number down.
A. Normal thread tension for straight stitch sewing.
B. Thread tension too loose for straight stitch sewing. Turn dial
to higher number.
C. Thread tension too tight for straight stitch sewing. Turn dial
to lower number.
D. Normal thread tension for zig zag and decorative sewing.
- Proper setting of tension is important to good sewing.
- There is no single tension setting appropriate for all stitch
functions, thread on fabric.
- A balanced tension (identical stitches both top and bottom) is
usually only desirable for straight stitch construction sewing.
- 90% of all sewing will be between "3" and "5" ("4" is basic
setting).
- For zig zag and decorative sewing stitch functions, thread
tension should generally be less than for straight stitch
sewing.
- For all decorative sewing you will always obtain a nicer stitch
and less fabric puckering when the upper thread appears on
the bottom side of your fabric.
Correct thread tension is when a small amount of the upper
thread appears on the bottom side of fabric.
To test the bobbin thread tension, remove the bobbin case and
bobbin and hold it by suspending it by the thread. Jerk it once
or twice. If the tension is correct, the thread will unwind by
about an inch or two. If the tension is too tight, it does not
unwind at all. If the tension is too loose, it will drop too much.
To adjust, turn the small screw on the side of the bobbin case.
Lower thread tension
B A
C D
15
Thread tension
1 2
4