Combining force-sensing load cell with Vdc servomotor, Model M15-W generates torque as low as 0.000014 oz-in. (analytical mode) or 0.0000028 oz-in. (averaging mode) at speeds down to 0.001 rpm. System reveals minute variations in rotational consistency, pinpointing such defects as brinneling, contamination, and shaft misalignment. Windows-based software lets user program complex, multistep tests. User sets rotation in 1/10 deg increments from 1-3,600 deg; speed from 0.001-4 rpm, CW or CCW; Y-axis torque; and trigger and display conditions. Test results export with ease to MS Excel.