7. CORRECT￿ USE

￿

￿-￿. 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.

[Stitch patterns]

 

Whip stitch (plain stitch)

 

Purl stitch (seal stitch)

Front

Back

Front

Back

1228Q

1229Q

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

Whip stitch

 

 

Purl stitch

 

Upper thread

Polyester #50

Spun #60

 

 

Polyester #50

 

Spun #60

Lower thread

Polyester #50

Spun #60

 

 

Polyester #50

 

Spun #60

Upper thread tension (N)

0.3 - 0.7

0.40 - 0.75

 

 

0.75 - 2.00

 

1.0 - 2.5

Lower thread tension (N)

0.15 - 0.35

 

 

0.05 - 0.25

Thread take-up spring tension (mm)

 

 

4

- 6

 

 

Thread take-up spring height (N)

 

 

0.1

- 0.2

 

 

￿-￿-￿. Lower thread tension

Becomes weaker

Becomes stronger

Whip stitch (plain stitch)￿

Adjust by turning the adjusting screw (1) until the bobbin case drops when it is shaken slightly (0.15 -

0.35N) 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 -

0.25N) while the thread end coming out of the bobbin case is held.

2813Q

61

HE-800A