A roll was being lowered into the furnace. The bottom edge of the roll caught the inside of the donut ring, causing the roll to turn out of the rigging shoe. An employee reached for the roll to clean off a refractory that had fallen down, unaware that the roll was out of the rigging. The roll fell through the donut and crushed the employee's hand. The employee suffered an amputation to the first knuckle of the right index finger; the right-hand middle finger was also fractured.