J640/J641 Quick Reference Loading Ribbon Open the printer. Remove the old ribbon cassette. Slide a new ribbon cassette onto the printhead assembly. Loading Labels Open the printer. Grasp the handles to pull the supply holders apart and insert the roll of labels into place between the supply holders.
DO NOT touch the printhead with your hands. This may damage the printhead. Turn the power off and open the printer. Remove the label roll and ribbon cassette. Moisten a cotton swab with alcohol or use a cleaning pen. Rub it back and forth across the printhead, platen roller, peel bar, pinch rollers, peel blade, and tear bar to remove build-up.