Epson LQ-860 User Manual page 195

4. To remove slack in the new ribbon, turn the ribbon-tightening
knob in the direction of the arrow.
Note: The film ribbon cartridge has a slightly different tightening
knob and comes with a white shipping spacer. Before installing a
film ribbon, remove the white tab spacer from the cartridge first.
5. Hold the ribbon cartridge while gently squeezing the two ridged
plastic tabs together; then lower it until it snaps into place. The
side hooks in the printer fit into the slots on each side of the
ribbon cartridge.
6-6 Maintenance