This apparatus is primarily for applying the graphite coating to the axle. Electric drills or drill presses rotate too fast and more graphite may be rubbed off than is applied. The polished axle is chucked into the pin vise and rolled back and forth by hand so the axle rotates against the special application cloth containing Super-Z graphite. The proper pressure and rotating technique are specified in the instruction sheet. Remember we are trying to create a fairly delicate monomolecular film on the axle surface.