Adjustment Of Needle Bar Height - Pfaff expression 2014 Service Manual

13. Adjustment of needle bar height

This machine has a transverse double-rotating hook.
On the right zigzag penetration, the sewing hook reaches the needle a little earlier and at the left penetra-
tion a little later than at the center penetration. Thus the looper point is positioned slightly higher above
the needle-eye for the right zigzag penetration than for the left zigzag penetration (fig. 38).
Requirement:
The distance between the top edge of the needle eye and the lower edge of the sewing hook point must
be 0.5 mm at the widest left zigzag penetration (fig. 39).
Check:
Select stitch program "03" and the widest zigzag width of 6 mm.
Turn the handwheel until the needle rises at the left zigzag stitch and the sewing hook point is exactly
behind the center line of the needle.
The distance between the top edge of the needle eye and the bottom edge of the hook point must be
0.5 mm.
Adjustment:
Loosen screw 58 just a little (fig. 40).
Shift needle bar 59 in height, without twisting it, until the clearance of 0.5 mm is set.
Tighten screw 58 securely.
Cross-check:
Check the clearance of 0.5 mm.
The needle holder must face exactly square to the right.
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