A CNC machine is a machine that offers increased flexibility and productivity. CNC stands for Computer Numerical Control. The machines are automated milling devices that use coded instructions and programs to make parts. The programs are sent to the machines using an internal computer. There are many different types of CNC machines including machines that are retrofitted or custom built for CNC operation. Common CNC machines are milling machines and a lathe. Other machines include grinders and cutters. 

 

 

There are few main types of CNC machines used in metal shops as well as production shops around the world today

 

Machines that are Retrofitted

 

 

Milling machines are often retrofitted with CNC technology. This process involves removing all the mechanisms built into the machine to make it easy for a human to operate, such as: hand wheels and DRO (Digital Read Out) electronics.

 

The machine will usually have its old lead screws replaced with new very high accuracy ball screws and various new mounts built for mounting the actuators to the machine.

 

Just like the milling machine, lathes are also commonly retrofitted with CNC technology in the exact same way.

 

 

CNC Routers are a very common piece of machinery you will see a lot when learning about CNC. These are machines built exclusively to be operated by CNC technology and have no human interface other than through the computer.

 

Routers are generally for producing larger work and more commonly built with the idea of cutting wood, plastics and sheet metal in mind. Routers also are most commonly found in a 3 axis setup (X, Y and Z). This set up will allow cutting of basic profiles and 3 dimensional relief machining. There are also CNC router which are 4, 5 or even 6 axis, these machines are more suited towards cutting more complex shapes or prototype models.

 

There are many milling machines today which were built specifically for CNC as opposed to being retrofitted at a later stage. Some of these machines can be absolutely massive and have built in tool changers, auto-feed mechanisms for loading in material and various electrical sensors for safe monitored cutting.

 

CNC plasma cutters are very similar to CNC routers in size and setup, however plasma cutters don’t require as much of a powerful set up because as opposed to dragging around a spinning tool in material they fly above the table with a plasma torch.

Plasma cutters are made for cutting 2 dimensional profile shapes into sheet metal.

 

CNC laser cutters follow the same principle as the plasma cutter. However laser cutters use a much less destructive force than a plasma torch – A laser. Laser cutters are often good for cutting wood, plastic and metal. Each will need a different strength of laser suited for the material.

 

A 3D printer or 3 Dimensional printers uses a similar set up as a CNC router or laser cutter, except it uses a plastic extruder. This plastic extruder pushes out hot plastic through a tiny hole and slowly, layer by layer deposits enough plastic to build up a completed part.

 

A pick and place machine again uses a similar set up as a CNC router or laser cutter. This time there a multiple small nozzles, that pick up electrical components and then move into a desired location and place that electrical component down. Hence the names pick and place!

Pick and place machines move very quickly and are used to place the many hundreds or thousands of electrical components that make up devices such as computer motherboards, phones / tablets, and pretty much everything else that has a printed circuit board.