THE DRAGLINE CREW WAS REMOVING THE 2ND INTERMEDIATE PROPEL BEARING COVER RETAINER. THE COVER WAS COCKED & JAMMED SO THE CREW WAS ATTEMPTING TO USE A WEDGE TO STRAIGHTEN OUT THE COVER. THE INJ WAS HOLDING THE WEDGE WHILE ONE OF THE CREW ATTEMPTED TO STRIKE WEDGE WITH 16PD HAMMER. MEMBER MISSED WEDGE & STRUCK INJ RIGHT HAND CAUSING FRACTURE TO 4TH FINGER METACAPUS