The hand crank rotates in a 6" diameter circle 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 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 tung oiled walnut handle rotates freely on the crank arm.