DURKOPP ADLER H-Type 969 Service Instructions Manual page 75

Adjusting the thread system
Setting steps
1. Pull the thread in and wind it onto the bobbin.
2. If the thread is concentrated at one end of the bobbin, loosen screw (5)
3. Tighten the screw (5).
4. If no satisfactory result can be obtained by following point 2, incline the
Service Instructions 969 - 01.0 - 12/2015
and align the thread tensioning element (4) so that it is central to the
thread guide.
thread guide (3) using the setscrews (1).
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