Epson DLQ-3500 User Manual page 16

3. Facing the back of the printer, release the sprocket lock levers
by pushing them up.
* sprocket lock lever
4. Position the left sprocket so that the sprocket pins are to the
left of the arrow mark on the back of the printer. Then push
down the lock lever to lock the sprocket in place.
Note:
Printing starts at the arrow mark on the back of the printer.The
unprintable area is to the left of the arrow mark.
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