Thread Tension - Brother LH4-B800E Instruction Manual

7-5. Thread tension

The shapes of the seams for all patterns which have been stored in programs 1 to 90 can be set using
parameter No. 11. Make the following adjustments in accordance with the seam shape which has been set.
Lower thread tension
Stronger
(1)
1279Q
Whip stitch (plain stitch)
1. Adjust by turning the adjustment screw (1) until the bobbin case drops when it is shaken slightly (0.15 -
0.25 N) while the thread end coming out of the bobbin case is held.
2. Turn the tack tension control (2) to adjust the thread tension so that a clean whip stitch is obtained at the
bar tacking areas and the zigzag areas. There is no need to loosen the zigzag tension control (3) at this
time. Bar tacking stitches and zigzag stitches are sewn at the tension which is set by the tack tension
control (2), so that zigzag tension is automatically disabled. If the zigzag tension control (3) is loosened,
the upper thread trailing length after upper thread trimming may become longer.
Purl stitch (seal stitch)
1. Adjust by turning the adjustment screw (1) until the bobbin case drops gently by its own weight (0.05 -
0.15 N) while the thread end coming out of the bobbin case is held.
2. Turn the tack tension control (2) to adjust the thread tension so that a clean whip stitch is obtained at the
bar tacking areas.
3. Turn the zigzag tension control (3) while watching the looping of the zigzag stitch.
Upper thread tension
Weaker
Bar tacking stitch
1280Q
HE-8000
Zigzag stitch
7. CORRECT USE
(2)
(3)
2148Q
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