Setting The Hook Thread Tension - DURKOPP ADLER 275 Series Operating Instructions Manual

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4.7.2

Setting the hook thread tension

Fig. 13: Setting the hook thread tension (1)
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(1) - Bobbin
(2) - Braking spring
The braking spring (2) and tensioning spring (3) together deter-
mine the hook thread tension. The braking spring (2) also prevents
the bobbin from running on when the thread is cut.
Proper setting
• The thread interlacing should be exactly in the middle of the
material being sewn.
• If the loose thread end is held tightly, then the spool housing
should slowly lower through its own weight when the
bobbin (1) is full.
• The total value of the hook thread tension should be applied
50% respectively through the braking spring (2) and the tensi-
oning spring (3).
To set the hook thread tension:
1. Turn back the adjusting screw (4) such that the tension on the
tensioning spring (3) is completely removed.
2. Bend the braking spring (2) such that 50% of the recommen-
ded hook thread tension value is applied through the braking
spring (2).
3. Insert the bobbin into the spool housing upper section and
thread in the hook thread.
(3) - Tensioning spring
(4) - Screw
Operating Instructions 275 - 02.0 - 08/2019
Operation
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