The hand crank has a 3" radius handle which allows steady slow turning if necessary. The high count, high rise or sharp pointed cam lobes need to be turned very slow to produce a smooth cut. The actual cranking ratio is 9 turns of the crank to 1 turn of the spindle. One revolution per minute for the spindle is not uncommon.
A very important feature of the RRE is the location of ball bearing round drive belt idler pulleys. The torque vector or rotational force of hand cranking is directed exactly through the spindle head pivot point by the idler pulleys. This keeps the spindle head in perfect balance no matter how large the torque forces originating from irregular hand cranking or resistance from high rise rosette cam lobes. Therefore, none of the cranking force will add to the spring tension force keeping the rosette cam in contact with the cam lobe. The hand cranking forces will not add to the force of the rubber climbing the rosette cam lobe. This minimizes the cam lobe disengagement from the rubber or cam hop and much less spring pressure is required for consistent cam to rubber contact. The routing of the drive belt determines the amount of cranking force that is directed through the headstock into (or away from) the rubber rather than into spindle cranking force.
A round belt is used to assure smooth vibration free cranking action. The crank is located at the mid point of the spindle head for convenient cranking motions. The secondary drive belt tension is controlled by spring pressure on a ball bearing idler pulley block.