An employee was rigging a piece of metal that weighed 434 pounds. He hooked the clamp to the gantry crane and stood the base plate on its end to check the balance and placement of the clamp. The employee then raised the plate and swung it over to the steel column. The baseplate bumped into the column and the clamp released. The employee's index, middle, and ring fingers were lacerated by holes in the base plate as it slipped against the column and fell to the floor. The index and middle fingertips were amputated.