Abrasive machining includes grinding, honing, and lapping. It is used when traditional cutting tools cannot cut hardened steel or achieve the required finish. Machinists use it to finish crankshaft journals and cylinder bores. The tiny abrasive grains cut small chips, leaving a smooth surface.
Cylinder honing is a key step during engine rebuilds. It leaves a crosshatch pattern on the cylinder walls. This pattern holds oil, allowing the piston rings to seat and seal. Without this finish, the engine would burn oil.