Upper Thread Tension Unit - Singer Futura XL-550 Service Manual

22. Upper thread tension unit

Check
1. Always check so the bobbin thread tension is correct before the upper thread tension is checked.
2. When the thread tension dial is set at "S", a correct take-up should be obtained at straight stitching and
zig-zag using normal cotton fabrics and polyester thread.
Adjustment
NOTE! Before any adjustment is done remove any loose pieces of thread or
fl uff from the thread tension discs
1. Always check so the bobbin thread tension is correct before the upper th-
read tension is adjusted.
2 Remove the face cover.
3. Turn on the main power and tension will be set at default "S" position.
C
A
Then turn it off.
4. Remove two screws (B) , then remove sensor board (A).
5. Remove screw (C) and then the adjustment dial.
6. Rotate Thread tension wheel (E) to adjust tension to be set.
Standard is 55-65gr at "S" position. B
- Rotate anticlockwise to increase tension.
- Rotate clockwise to decrease tension.
Adjust tension while measuring it by tension gauge.
E
7. Fit the dial to Thread tension wheel after adjustment.
It is needed to fi t the dial at same position as it was before taking it off.
Tighten screw with washer at the Thread tension wheel.
8. Attach sensor board (A) by two screws.
After attaching sensor, rotate dial clockwise and tip of dial must be crossed center of the sensor when dial
reaches not rotatable position (To insulate electric signal).
An error will occur when tip of dial is not crossed center of the sensor.
9. Turn on main power so the dial will rotate to the default position and
then check to see if the tension is correctly set at the favorable setting.
Singer Furura XL-550 27