drive motor 122 drive pulley bearings 126 mounted on the drive unit strut 130 and a belt 114 connecting the drive pulley 124 and the drive couplings 24 where more than two drive couplings 24 are used the belt 114 would connect couplings 24 and drive pulley 124 in a known serpentine manner motor torque is controlled by for example computer software or one or more appropriate hard wired controller s motor speed is controlled by the balance between motor output torque and bearing friction resistance torque in the embodiment shown the bearing friction is supplied by tailstock bearings 20 drive coupling bearings 112 and drive pulley bearings 126 the drive motor 122 rotational speed equals a tube 40 rotational speed motor speed is proportional to the amount of drag in the bearing drive system the greater the bearing drag the lower the steady state speed the lower the bearing drag the higher the steady state speed as the motor rpm increases the bearing friction increases due to bearing grease shear and or tube 40 vibration until bearing friction matches motor torque when bearing friction equals motor torque the rotational speed becomes approximately constant rotational speed should be for example in a range of about 3000 rpm to about 4000 rpm if no tube 40 is mounted in the spinner the motor may overspeed and automatically shut down by using the appropriate overspeed detection circuits motor overspeed occurs at for example about 5000 rpm spinning time.