Canon Color ImageRunner C3380 Reference Manual page 115

When you use the stack bypass to make copies, straighten out curled papers
prior to use, as shown below. Curled paper may cause a paper jam.
Feeding Direction
To print on the back side of preprinted paper, load the preprinted paper face
down into the stack bypass, as shown in the illustration below.
Output
Direction
After the first one-sided
copy is made
IMPORTANT
When loading paper into the stack bypass, align the paper stack neatly between
the slide guides. If the paper is not loaded correctly, a paper jam may occur.
NOTE
•
If there are instructions on the paper package about which side of the paper to
load, follow those instructions.
•
When the paper is loaded into the stack bypass, the side facing down is the one
printed on.
•
If problems, such as poor print quality or paper jams occur, try turning the paper
stack over and reload it.
•
For more information on the print direction of preprinted paper (paper which has
logos or patterns already printed on it), see "Relationship between Original
Orientation and Preprinted Paper Output Chart," on p. 9-21.
Feeding
Direction
When copying on the back
side of a preprinted sheet
Making Prints Using the Stack Bypass
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