Adjusting Nedle Thread Tension - Bernina Deco 330 Operation, Service Manual & Parts List

Deco 330
The standard upper thread tension should be 51 to 59 grams when the tension dial
is set at "3", measured with a #50 polyester thread being pulled at approximately 110
mm/sec. in the direction of arrow.
1
Adjusting Needle Thread Tension
(B)
(A)
1 Set the Thread tension dial at "3".
2 Lower the presser foot.
3 Remove the front cover unit and adjust the thread
tension.
(A) If the thread tension is more than 59 g
................... turn the screw in the direction of "B".
(B) If the thread tension is less than 51 g
.................. turn the screw in the direction of "A"
1 Pulling direction: (Pulling speed 110 mm/ Sec.)
4 Attach the front cover unit.
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