Adjusting The Thread Tension; Adjusting The Hook Thread Tension - DURKOPP ADLER 838 Instruction Manual

6.4

Adjusting the thread tension

6.4.1

Adjusting the hook thread tension

3
Caution: danger of injury!
Turn off the main switch.
Adjust the shuttle thread tension only when the sewing machine is
turned off.
–
Adjust the shuttle thread tension by turning the screw (1) with a
screwdriver. The screwdriver should be inserted through the
opening (2). The tension is increased by tightening the screw.
–
The thread tension should then be checked with a thread tension
gauge (dynamometer). Insert the thread as shown in the illustration
and pull in the direction of arrow (3).
The thread tension set at the factory depends on the selected
machine configuration (see table below). This tension setting is
suitable for typical sewing processes. You should lower the tension
when working with materials which are soft and thin. If the seam
must be tightly sewn, then you should increase the tension while
simultaneously lowering the sewing speed.
Average values for hook thread tension
Type of sewing
heavy
extra heavy
2
Width of needle used
Nm
120-160
180-230
1
Thread tension in
grams
90
90
11
GB