Pfaff 521 Instruction Manual page 75

Adjustment
Loosen screws 5.
Bring the needle bar to 2.0 after BDC.
Place the adjustment pin (Part no. 61-111 641-39) into hole 6 and place under pressure.
Position the hook point at the middle of the needle and tighten screws 5.
Set the needle height in accordance with requirement 2.
Remove the adjustment pin from hole 6.
Align needle guard 4 in accordance with requirement 3 by turning the eccentric 7
(screw 8).
Screws 3 remain loosened for further adjustments.
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