EMPLOYEE WAS IN THE PROCESS OF REMOVING A FILTER HOUSING FROM THE DRILL, AS EMPLOYEE WAS REMOVING ONE OF THE LAST BOLTS FROM THE HOUSING IT PIVOTED ON THE REMAINING BOLT CAUSING HIS FINGER TO BECOME WEDGED BETWEEN THE HOUSING AND THE COMPRESSOR TANK. THE BOTTOM PART OF THE HOUSING HAD BEEN REMOVED EXPOSING A SHARP EDGE.