Abstract: Employee #1, engaged in a core drilling operation, had completed a core hole in the floor of a building under construction and manually retracted the bit. The core stuck in the bit and, because it was fitted with an extension, Employee #1 was unable to raise it high enough to remove the core. He decided to lay the machine on its side and began to remove the bolts securing the base to the floor. As he steadied the head and column with his right hand, the head dropped due to loosening of the friction holding device. His right ring finger was pinched between the head and the gear teeth on the column; the fingertip was amputated.