Abstract: On July 19, 1991, Employee #1 was turning the outside diameter of a diaphragm being repaired to specifications on an Axelson metal turning lathe. The cast iron part being turned was 23 1/2 in. in diameter by 2 in. thick, with a new band added to the outer circumference. This part had been cut into halves in the repair process. The cast iron halves had been tack welded to a round piece of mild steel stock, about 10 1/2 in. in diameter. The employer used Ceryanium 889sp AC-DC 125 amp, 1/8 in. diameter rod to tack these two dissimilar metals together. The round piece of stock, with the cast iron halves tacked to it, was chucked into the lathe. A piece of steel, 2 in. wide by 6 in. long by 1/2 in. thick, was placed against the cast iron pieces and the tail stock was placed against this additional piece of steel while pressure was applied toward the chuck of the lathe, to help hold it in place. The working range of the lathe is from 16 RPM to 555 RPM. When Employee #1 started the lathe, the cast iron halves separated at their tack points from the mild steel stock. After separation, one half was found lying on the back side of the lathe on the opposite side of the operator. The other half flew through the air, grazing the employee's head, and was found 25 1/2 ft from the lathe, on the operator's side. There were no witnesses although some employees did hear the peculiar sound of the lathe at high speed. In fact, the lathe was found in the 555 rpm working range when stopped by a coworker after the accident. Employee #1 has experienced some memory loss and other problems. He is in therapy.