Demolishing concrete is a heavy-duty task that calls for heavy-duty tools. Most concrete demolition projects call for the use of a jack hammer or hammer drill. Occasionally, very small areas of concrete must be removed from a larger project, or you may simply need to clean up the ragged edges left by a larger tool. These situations call for the use of a cold chisel. This small, pointed piece of metal can make precision cuts in concrete when used properly.
Grasp the cold chisel loosely in your fist placing the tip of the chisel against the concrete you intend to break. Lean the chisel so that only one point of the tip is resting on the concrete.
Grasp the bottom end of the handle of a small sledge hammer tightly. Tap the head of the chisel with a half-swing and immediately strike it again with a full swing. Continue digging a hole in the concrete with only one point of the cold chisel using a half-strike/full-strike double tap of your sledge.
Lean the chisel perpendicular to the angle of the first angle so that the full width of the blade rests against the concrete and the bevel is parallel to the surface of the concrete.
Strike the head of the chisel with your hammer with the same half strike/full strike maneuver to remove larger chunks of concrete.
Reposition the chisel with the width of the tip resting flat and the bevel parallel to the surface of the concrete and remove another small chunk with the double tap maneuver. Continue moving the cold chisel and removing small chunks until the job is complete.