Printronix P7000 Quick Reference Manual page 13

CAUTION
To avoid damage to the printer caused by printing on the
platen, always position the left tractor unit directly to the left of
the "1" mark on the paper scale.
Tractor Splined Shaft
Figure 7. Using the Paper Scale as a Guide
6. If adjustment is necessary:
a. Unlock the left tractor.
b. Slide the tractor until it is directly to the left of the number
"1" on the paper scale and lock it. You can also use the
paper scale to count columns.
c. Lock the left tractor.
Loading Paper (Standard Configuration)
Paper
Tractor
Paper Scale
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