Ricoh Aficio 551 Copy Reference Manual page 192

Copying
A
Press the [Edit/Stamp] key.
2
B
Press the [Erase] key.
C
Press the [Center] key.
D
Set the erase center width with the [n] and [o] keys. Then press the [OK]
key.
Note
To change the value entered, press the [n] and [o] keys and enter the new
value.
E
Set your originals, then press the {Start} key.
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