Typical profiles include straight cuts, mitres, saddles and midsection holes.
These complex cuts are usually required to allow a tight fit between two parts that are to be joined via arc welding.
However, its efficiency diminishes as the alloy content of the material increases, limiting its applicability for high-alloy steels.
For some applications it is necessary to remove this material by mechanical means, such as grinding or machining, prior to use or further fabrication by welding.
The synchronization of axes is accomplished either mechanically, via cams, levers and gears, or electronically with microprocessors , which is computer numerical control (CNC).