Epson LX-810 User Manual page 183

Replacing the Ribbon
7. Use a pointed object, such as a ball-point pen, to guide the
ribbon into place between the print head and ribbon guide
while you turn the ribbon-tightening knob. Be careful not to
puncture the ribbon.
8. Slide the print head from side to side to make sure that it
moves smoothly. Also make sure the ribbon is not twisted or
creased.
Maintenance 6-7