Operating instructions

Operation
Operating Instructions 650-16 - 01.0 - 06/201432
5.6 Setting the hook thread tension
Correct setting
The hook thread tension must be set so that the resulting stitch
pattern looks like the figure in  5.2 Setting the needle thread
tension, page 26.
At the recommended hook thread tension of e.g. 25 g (measured
with a full bobbin), 12.5 g should be generated by the braking
spring and 12.5 g by the tensioning spring.
The basic setting for the tensioning spring is performed as follows:
When the bobbin housing contains a full bobbin it must sink slowly
under its own weight.
Figure 9: Bobbin housing sinking
The braking spring prevents the bobbin running on when the
thread has been cut.
Risk of injury from moving parts
Switch off the sewing machine before replacing the
hook thread bobbin.
WARNING