English: Fly cutting is the process of optimising the cutting path when cutting areas such as grids of holes on sheet metal material, usually with a CNC laser. Instead of cutting each individual hole (which requires the axis to stop when changing direction) the machine will cut a single line and then return in the opposite direction to cut the line below, continuing until all horizontal cuts have been completed in the array. It will then continue to make the vertical cuts. A radius will often be placed on each turn, meaning that the machine does not have to stop in one axis to start movement in the other. This can drastically reduce the cutting time of parts with large grids of holes. Also referred to as Grid Cutting.