ADJUSTING THE THREAD TENSION; Adjusting the Upper Thread Tension; Adjusting the Tension of the Bobbin Thread- Page 14

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ADJUSTING THE THREAD TENSION

After sewing trial stitches and checking the sewing results, adjust the thread tensions if necessary. After adjusting the 
tensions, be sure to sew trial stitches again in order to check the sewing results.

Adjusting the Upper Thread Tension

We recommend an upper thread tension that is higher 
than the standard setting.
Refer to the machine’s Operation Manual for detailed 
instruction.

Adjusting the Tension of the Bobbin 
Thread

If the desired stitching cannot be achieved after 
adjusting the upper thread tension, adjust the tension of 
the bobbin thread. The tension of the bobbin thread can 
be adjusted by turning the slotted-head (–) screw on the 
bobbin case (gray) for bobbin work.

a

Do not turn the phillips screw (+).

b

Adjust with the small screwdriver.

To increase the tension of the bobbin thread, turn the 
slotted-head (–) screw 30° to 45° clockwise.

To decrease the tension of the bobbin thread, turn the 
slotted-head (–) screw 30° to 45° counterclockwise.

Note

• Turning the screw on the bobbin case (gray) may 

push up the spring plate, as shown below.
If this occurs, gently press down the spring plate 
with a screwdriver so it is lower than the top surface 
of the bobbin case (gray), and then insert the bobbin 
case into the machine.

a

Spring plate

 CAUTION

• DO NOT adjust the position of the phillips (+) 

screw on the bobbin case (gray) as this may result in 
damage to the bobbin case, rendering it useless.

• If the slotted screw (-) is difficult to turn, do not use 

force. Turning the screw too much or providing 
force in either (rotational) direction may cause 
damage to the bobbin case. Should damage occur, 
the bobbin case may not maintain proper tension.

Note

• If the bobbin thread tension is tight, the thread 

cannot be passed through the tension spring when 
the bobbin is installed in the bobbin case. (Refer to 
“When tension is not applied to the bobbin thread” 
on page 6.)