Things You'll Need
Measuring tape (optional)
Masonry sandpaper (optional)
Cinder blocks are rectangular masonry units typically used for foundation forming or temporary concrete installations. Most units are made from concrete aggregates and cinder ash. The blocks are usually chalky gray and are relatively lightweight. Though light, the blocks possess high structural strength when cemented together. Cinder blocks are available in several different lengths, but project circumstances may require a full-size unit to be split.
Draw a guiding line on the part of the cinder block you wish to split using chalk and a ruler. Find the length of the block using a measuring tape and divide it by 2 if you wish to split the block in half.
Turn the block over and make an identical guiding line.
Position the chisel blade at the edge of the guiding line and tap the end of the handle firmly with a hammer. Tap every inch across the length of the line.
Flip the block over and repeat the above step for the second guiding line.
Lift both pieces of cinder block and check the split edges for a clean cut. Chisel away any protruding fragments and use masonry sandpaper to smooth the edges, if desired.
Use thick gloves and safety glasses while cutting to protect your skin and eyes from flying concrete fragments and dust.
Wield the chisel with caution. Most chisel blades are very sharp and can cause personal injury if handled without proper care. Work away from children or pets.