Working with concrete necessitates the use of specialised tools that will stand up to concrete. A concrete cold chisel, sometimes known as a brick set, is a wide, flat-bladed, relatively dull chisel. A brick set is a wider version of a chisel, whereas a concrete cold chisel is narrower for small surfaces and more precise cutting. Manufacturers make concrete cold chisels from hardened steel, which will not break from the stress of applied force on a masonry surface.
Mark a line on the concrete paver or block where you plan on cutting with a piece of chalk.
Drag the edge of the concrete cold chisel back-and-forth across the line while exerting pressure on the chisel to score a line on the concrete block or paver. The wider the concrete cold chisel blade, the smoother the break in the block or paver.
Set the concrete block on a bed of sand.
Place the edge of the concrete cold chisel into the scored line and strike the handle of the cold chisel with a masonry hammer. Reposition the cold chisel on the scored line and strike with the masonry hammer. Continue to reposition the concrete cold chisel and hit with the masonry hammer until the concrete block or paver breaks.
Position the concrete cold chisel almost parallel to excess mortar or concrete between blocks or stones. Occasionally excess concrete runs out from between masonry building materials and dries, leaving behind an unsightly hardened drip.
Place the flat end of the chisel onto the excess mortar and hit the concrete cold chisel with a masonry hammer.
Continue to position the concrete cold chisel up to the hardened concrete and tap the concrete cold chisel with a masonry hammer until no excess concrete protrudes from the surface.
Position the concrete cold chisel on a jagged line along a wide crack. Straightening wide crack lines with a concrete cold chisel when making repairs results in a longer lasting repair patch.
Strike the concrete cold chisel's handle with a masonry hammer to cut off the jagged edges making them smooth.
Move the concrete cold chisel along the length of the concrete crack on both sides of the crack and strike with a masonry hammer until the crack has straight edges.
Wear eye protection, gloves and a dust mask when using a concrete cold chisel.