CNC Milling vs. CNC Turning: All You Need to Know
CNC machining is a rapid manufacturing process that turns digital 3D designs into plastic or metal parts by selectively cutting away material. Many companies require CNC machining service to make parts and prototypes, and many industries use the versatile technology.
But CNC machining comes in various forms. Although all CNC machining technologies follow a similar workflow — software turns the digital design into machine instructions, which instruct the CNC machine to cut material — the hardware for cutting material can differ greatly between machines.
This article discusses the main differences between two of those machines: CNC mills and CNC turning (or lathes centers).
In the article we discuss the essential features of CNC milling parts and CNC turning while also presenting the main advantages of each technology and a selection of common parts that companies can manufacture using each process.
CNC milling is one of the most common CNC machining service, and machinists can use it to make a wide variety of CNC machined parts. Prototype companies often use CNC mills to make one-off functional prototypes.
CNC mills use computer instructions to move a rapidly rotating cutting tool along three or more axes. When the spinning cutting tool makes contact with the workpiece, it removes material in a controlled manner. The cutting tool makes a succession of passes against the surface of the workpiece until the workpiece resembles the desired part.
Most CNC mills keep the workpiece stationary, holding it down on the machine bed with a vice. However, multi-axis CNC mills may rock or rotate the workpiece to create a greater number of cutting angles. This allows the machinist to create more complex parts without having to manually reorient the workpiece.
Providers of rapid prototyping services use CNC machining because it is a one-stop, end-to-end process with short lead times.
CNC turning is a form of CNC machining that machinists use to make rounded, cylindrical, and conical parts. Although it is less versatile than CNC milling, it is one of the most popular CNC machining services and rapid prototyping services.
Machines that carry out CNC turning parts are called CNC lathes or CNC turning centers. They are different from CNC mills in that they rapidly rotate the workpiece in a chuck but do not rotate the cutting tool. The cutting tool, affixed to a turret, moves towards the spinning workpiece under computer instructions and removes material where necessary.