In general, the thread tension is to be adjusted
in accordance with materials thread and others.
In practice, the thread tension is adjusted ac-
cording to the stitches resulted to get the normal
stitches.
When adjusting the bobbin thread tension,
turn bobbin case tension spring screw (A) clock-
wise for more tension or turn the screw counter
clockwise for less tension.
It is a common practice to check the bobbin
thread tension. In case of polyester thread 50=,
hold the end of the thread. If the bobbin case falls
down slowly, the proper tension is obtained.
The needle thread tension should be ad-
justed with referance to the bobbin thread ten-
sion. The needle thread tension can be adjusted by
changing tension of the thread take-up spring ,sew-
ing range of the thread take-up spring, tension of
tension disc, and the position of thread guide.
.
.
.
.
.
The normal sewing range of thread take-up sping
is 5~8mm. For sewing light weight materials( short
stitch), weaken the spring tension and widen the
sewing range of spring, while for sewing heavy
weight materials, strengthen the spring tension and
shorten the sewing range of spring .
1) Adjusting the thread take-up spring tension
(Fig.18) .
Loosen tension stud set screw (A), turn ten-
sion stud (B) clockwise to make the spring get
more tension, or turn the tension stud counter
clockwise to make the spring get less tension, After
adjustment, Be sure to tight tension stud set screw (A).
The method of adjustment:
Loose set screw (A) first, then to turn tension
stud(B) counter clockwise to release the tension of
:
19.Adjusting the thread take-up spring (Fig 18
、
19)
18.Adjusting the thread tension(Fig 16
、
17)
18
16
-8-
17
A
B
C
A
B
A
