Oki PT390 Manuel D'utilisation page 41

Then, press the FEED switch for one second or longer to accept
the selection. The printer enters cutter cleaning mode. The
printer prints the following and cuts the paper when it enters
cutter cleaning mode:
CUTTER CLEANING
1. Open Cover, and remove Roll Paper.
2. Push FEED switch to move Cutter to
3. When cleaning is completed, set
(4) Press the FEED switch to move the cutter to a position that will
facilitate cleaning, and then clean the cutter.
(5) After completing cleaning, reposition the roll paper, and close the
top cover.
the cleaning position.
Roll Paper, and close Cover
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