Hard steel, or hardened steel, is often used in industrial machinery, safes and automobile parts, among other things. Drilling into hardened steel is a bit more difficult than drilling into sheet metal or other softer metals. It requires a carbide drill bit, which is harder but also more brittle than other bits, which means it breaks more easily. For this reason it is preferable to use a drill press rather than a hand drill when boring into hard steel.
Remove the bit that is in the drill press by inserting the key into the holes around the chuck. Turn the key counterclockwise in each hole until the old bit falls out.
Keep loosening the chuck until it is large enough to hold the carbide bit. Place the smooth end of the carbide bit in the chuck and tighten it in place by turning the key clockwise in each hole.
Mark the spot on your steel where you wish to drill.
Place the steel onto the drill press. Lower the bit onto the steel while the machine is turned off to make sure that the bit will bore into the steel in the correct location.
Open the clamps by unscrewing them or pressing the release switch. Place the clamps over the steel with the top end on the piece to be drilled and the bottom end under the table. Tighten the clamps by using the screw or pumping the hand tightener.
Turn on the drill press. Slowly lower the drill bit into the steel by pulling down on the lowering lever. You may need to exert quite a lot of pressure to get the bit to break into the steel. Once the hole has been drilled, raise the drill bit back up by moving the lever up.
If the hole you need to drill is large, drill a smaller hole, then put the larger bit into the drill press and drill again. The larger bit will have less material to remove, making the job that much easier.