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4.3.4) Tension Adjustment
1) Adjustment of Upper Thread Tension
Turn the tension adjusting nuts of the main and sub
thread adjusting devices clockwise, and the tension
of the upper thread will grow strong. If they are
turned in the opposite direction, the tension of the
upper thread will grow weak.
Adjust the thread tension in accordance with the
sewing conditions including sewing materials,
thread, and number of stitches
2) Adjustment of Thread Take-up Lever Spring Tension
Adjust the tension of the thread take-up lever spring
by turning the bolt on the main thread adjusting
device axis with a drive. If the bolt is turned
clockwise, the thread take-up spring tension is
strengthened. Otherwise, the tension is weaker. (The
standard movement volume is 6-8mm, and the
standard tension is 30-50g.)
3) Adjustment of Lower Thread Tension
If the bobbin case tension adjusting screw is turned
clockwise, the lower thread tension grows stronger. If
the bobbin case tension adjusting screw is turned
counter-clockwise, the lower thread
’
s tension grows
weaker.
Weaker
Stronger
Tension Adjusting
Screw
Sub Thread
Adjusting Device
Main Thread
Adjusting Device
