Thread Tension; Lower Thread Tension - Brother HE-800B Instruction Manual

4-5. Thread tension

The shapes of the seams for all patterns which have been stored in programs 1 to 50 can be set using parameter No. 53.
Make the following adjustments in accordance with the seam shape which has been set.
[Stitch patterns]
Whip stitch (plain stitch)
Front
1228Q
Whip stitch (plain stitch)
The above stitch pattern in which the upper thread moves over the top and the bottom thread moves over the bottom of the
material in a zigzag pattern is called a "whip" stitch. This pattern is identical to the zigzag pattern of a lock stitch zigzag
machine.
Purl stitch (seal stitch)
The above pattern in which the upper needle thread tension is high and the upper needle follows a straight line through the
seam center while the lower thread moves left to right and intertwines with the upper thread is called a "purl" stitch.
[Reference thread tension]
Stitch patterns
Upper thread
Lower thread
Upper thread tension (N)
Lower thread tension (N)
Thread take-up spring tension (mm)
Thread take-up spring height (N)

4-5-1. Lower thread tension

Back
Polyester #50
Polyester #50
0.3 - 0.7
Becomes
weaker
Becomes
stronger
Front
Whip stitch
Spun #60
Spun #60
0.40 - 0.75
0.15 - 0.35
4 - 6
0.1 - 0.2
Whip stitch (plain stitch)
Adjust by turning the adjusting screw (1) until the bobbin
case drops when it is shaken slightly (0.15 - 0.35 N) while
the thread end coming out of the bobbin case is held.
Purl stitch (seal stitch)
Adjust by turning the adjusting screw (1) until the bobbin
case drops gently by its own weight (0.05 - 0.25 N) while
the thread end coming out of the bobbin case is held.
2813Q
HE-800B
4. PREPARATION BEFORE SEWING
Purl stitch (seal stitch)
Back
Purl stitch
Polyester #50
Polyester #50
0.75 - 2.00
0.05 - 0.25
1229Q
Spun #60
Spun #60
1.0 - 2.5
26