a
b
18.Installing the bobbin (Fig.14)
19.Adjusting the threrad take-up spring (Fig.15)
20.Adjusting the tension of bobbin
thread and needle thread (Fig.16)
6
14
15
16
The thread tension should be adjusted according to
the materials, thread and stitch seam.
The bobbin thread tension can be adjusted by the
screw shown in the Fig.14
Based on it, the needle thread tension can be
adjusted through the thread take-up spring, tension
disc and the position of thread guide.
.
.
.
Increase
Decrease
Screw
The swing range of the thread take-up spring should
be 5~8mm. If stitch the light materials (stitch length
is also short), the spring tension should be lower and
increase the swing range, vice versa.
1. Adjust the tension of thread take-up spring
Turn the screw A clockwise to increase the tension,
o n t h e c o n t r a r y, t o d e c r e a s e t h e t e n s i o n .
2. Adjust the swing range of the spring
Loosen the screw A, turn the disc B clockwise to
increase the swing range, on the contrary, to
decrease the swing range.
Usually the tension and swing range have been set
by the maker, only sewing the special materials or
use special thread, it should be reset.
.
.
.
.
.
A
B
The normal stitch of sewing machine is shown in
Fig.a. If stitch is abnormal, the puckering and thread
breakage will occur, the needle thread tension and
bobbin thread tension should be adjusted so that the
normal stitch can be obtained.
a.If The stitch seam shows as Fig. B, indicates that
the needle thread tension is too tight or the bobbin
thread tension is too loose. Please turn the thread
tension nut counter-clockwise to release the needle
thread pressure; or turn the bobbin lace adjusting
screw with a screwdriver to increase the bobbin
thread tension.
B.If the needle thread tension is too loose or the
bobbin thread tension is too tight shown as Fig.c
Please turn the thread tension nut clockwise to
increase the needle thread pressure; or turn the
bobbin lace adjusting screw with a screwdriver to
decrease the bobbin thread tension.
C.If the stitch seam shows as Fig,d.e. It also can be
adjusted by referring to above methods.
.
.
.
.
a
b
c
d
e
a
b
