Operating instructions

5.7 Adjusting looper-thread tension
Caution: danger of injury
Turn off the main switch.
The looper-thread tension may only be adjusted with the
sewing machine switched off.
Adjusting brake spring 1 (class 69-FA-373)
On subclass
69-FA-373
the brake spring 1 prevents the bobbin from "running on" when
the machine halts or if the looper thread is wound off spasmodically.
–
Unscrew regulating screw 4 until no tension remains in tension spring 3.
–
Adjust brake spring 1 with regulating screw 5.
The braking force is correctly adjusted if brake spring 1 is about 1 mm above
surface 2.
Adjusting tension spring 3
–
Adjust tension spring 3 with regulating screw 4.
to increase looper-thread tension: turn screw clockwise
to reduce looper-thread tension: turn screw anticlockwise
For stitch formation see sketch a on page 12.
5.8 Fitting and changing the needle
Caution: danger of injury
Turn off the main switch.
The needle may only be changed with the sewing machine
switched off.
–
Turn the handwheel until the needle bar 6 reaches its highest position.
–
Undo screw 7.
–
Pull needle downwards out of needle bar 6.
–
Insert new needle
as far as it will go
into the hole in needle bar 6.
Caution:
When seen from the operating side of the machine the furrow 8 of the needle must
point to the rights(see sketch).
–
Tighten screw 7.
CAUTION:
When a thicker needle is fitted the distance from the
shuttle to the needle must bed corrected (see servicing
instructions).
Failure to comply with this instruction can cause the following faults:
when fitting a thinner needle: faulty stitches, damage to thread
when fitting a thicker needle: damage to the shuttle tip and needle
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