Adjustments; Belt Tension Main Shaft /Main Motor; Belt Tension Main Shaft /Base Shaft - Bernina activa 125 Service Manual

Adjustments

Important:
To enable the work described to be performed correctly,
the sewing machine must be in good mechanical and elec-
trical condition (running smoothly, properly oiled and all
plugs
in position). When the adjustments are carried out in the
correct order, the machine will sew perfectly.
Important:
For all adjustments and in case no other needle size is
given, always use a size Nm 80 needle. Before beginning
any adjustments the needle must be tested for being
straight! BERNINA uses needle system 130/705H TCN for
all adjustments.
Any service work being done on any machine, must be
done using the original accessories that were delivered
with the machine, or purchased later. These are:
Mains cable, foot control unit, automatic buttonhole foot,
zig zag foot, bobbin case and bobbin.
Tensioning the drive belt (motor)
Loosen the fixing screws 25a slightly.
•
Bring the motor into the desired position.
•
Tighten both screws.
•
Tensioning the drive belt (base shaft)
The belt tension is achieved automatically between the
tension roller and the tension spring.
Loosen the screw 46 slightly of the tension roller 47 hol-
•
der.
Turn handwheel backwards and forwards.
•
Tighten the screw 46.
•
46
47
33
25a
25a