CNC (Computer Numerical Control) machines function via pre-programmed instructions which are devised using CAD (Computer Aided Design) software. Once the layout is created it is converted into g-code. G-code is a CNC-legible format used to translate the CAD model into operation guidelines for a CNC machine, such as numerical values and coordinates.
CNC machines are extremely versatile; they come in various forms and can be used for a multitude of applications. Here are some examples of different types of CNC machines and their functions:
Milling machines are one of the most commonly found CNC machines; they tend to be used for drilling or cutting shapes into a hard, solid material. Rotary tools on the milling machine can shave and slice a material in varying directions, depths and angles and range from 3-6 axis structure. Find out more about CNC Machining in our CNC Machining guide.
Lathes are not too dissimilar to milling machines in that they both shape the desired material using spinning contact between the machine’s component and the object. However, while a milling machine tool spins and/or moves to work on the still material, the lathe rapidly rotates the material while introducing the tool to shave and shape the spinning object. Because of this method, lathes are best used for conical, cylindrical or spherical shapes.
CNC routers are typically used for large 2D projects such as cutting into sheets of aluminium, steel, wood or plastic. CNC routers are programmed to run along Z, Y and Z axes, otherwise known as the Cartesian coordinate system. Although there are 3D routers available for more detailed and complex work, the 2D is the most commonly operated.
Pick and Place Machines
Pick and place machines are used to relocate electrical components. They do this using various nozzles which attach to the desired constituent via vacuum and move it along the desired axes according to the pre-programmed coordinates. Pick and place machines are predominantly used for circuit boards in technology such as laptops, smartphones or tablets.
Laser and Plasma Cutters
Laser and plasma cutters tend to serve the same purpose and function, just through different means. They respectively use laser or plasma beams to cut detailed and precise designs into the desired materials. Laser cutters tend to be better suited to the more intricate enterprises, whereas plasma cutters are able to cut thicker sheet metals than laser. Plasma cutters harness the power of compressed gas whereas lasers utilise optical light.
Custom Built Machines
A lot of CNC machines have been retrofitted to suit modern technology, which means that many of their parts have been updated to keep up with the current capabilities. Custom-built machines, however, can be created with the latest technology inbuilt to suit whatever projects they will be most required for.
Like the aforementioned machines, 3D printers are pre-programmed via G-code. However, despite falling under the bracket of computer numerically controlled machines, 3D printing is often considered an outlier. This is because 3D printers use a method called additive manufacturing, whereas all the above machines are subtractive manufacturing machines. Subtractive manufacturing shapes an object by removing parts of it whereas additive manufacturing builds the design by projecting the desired material layer by layer.
Industries that utilise CNC machining include, but are not limited to, medical manufacturing, aerospace manufacturing, auto vehicle manufacturing, electrical manufacturing and general engineering.