Canon Staple Finisher-AA1 Service Manual page 183

5. Adjustment
3. Confirm that the paddle blade [1]stays in between the line [A] and [B].
[1]
[B]
[A]
CAUTION:
Adjust the phase angle of the paddle unit if the paddle blade is not in between the 2 lines.
CAUTION:
There are 2 paddle blades. So do not take the wrong blade to confirm its position.
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