a printer ribbon spool comprising an integral element , molded in one piece from a durable plastic composition , such as of nylon , has an elongate cylindrical ribbon support shaft of substantially uniform , relatively small diameter . one end of the support shaft functions as a first rotation bearing member for the spool , and the other end of the shaft is integral with a narrow , relatively large diameter gear having on the opposed surface thereof a second cylindrical rotation bearing member having a larger diameter than the diameter of the ribbon support shaft and of the first rotation bearing portion thereof .