Spex Logo

What’s the Difference Between CNC Milling & Turning?

What’s the Difference Between CNC Milling & CNC Turning

CNC machining is a process to machine precision parts. Most people will refer to any type of CNC operation as simply CNC machining. But, not all CNC processes and machines are the same. There are quite a few different types of CNC machines that are used for various operations. 

Two broader categories of CNC machining is CNC Milling and CNC Turning. 

These processes have similarities, but they’re not the same. If you’re planning a project, it’s important to understand which type of machine is best for you parts and design. Our team helps you decide how to machine your parts in the most efficient way, but you can read this post to learn more about the differences. 

What are the main differences?

The biggest difference is how the material is cut away to form the part. 

CNC milling rotates a cutting tool, while CNC turning rotates the part against a fixed cutting tool. Both processes take a bar of raw metal and removes material to form the part based on the design specifications. 

CNC turning is commonly used to form cylindrical and symmetrical parts and shafts. CNC milling is used for complex parts with square edges or multiple angles. Both machining processes are able to produce high quantities of parts efficiently. 

Both CNC milling and turning is used for various industries, including:

  • Automotive
  • Military/Defense
  • Medical
  •  Aerospace
  • Oil and Gad
  • And more

When cutting the material, CNC turning uses a single point cutting tool that is in continuous contact with the raw material. CNC milling uses multi-point cutting tools that make multiple cuts on the material. The difference makes turning more efficient for cylinder shaped parts, and milling is better for irregular shaped parts, or parts with multiple surface features. 

Turning vs Milling parts

What is CNC Turning used for?

CNC turning is used for many different parts in various industries. Most of the parts that are CNC turned are symmetrical, like precision rods, spacers, or shafts. You could also turn a part like a chess pawn like this video show, but a chess knight would be better to mill because they’re not symmetrical. 

Precision CNC turning uses a lathe that holds a round bar stock that spins around at high speeds. The rotation speed depends on the material being machined. Most CNC turning lathes can reach ±0.002″ tolerances, which is similar to milling. 

What is CNC Milling used for?

CNC milling is primarily used to machine more complex parts, square parts, and asymmetrical parts. Because CNC milling moves the cutting tool, machining can be performed on multiple axis. A basic milling machine moves the cutting tool on 3 axis: X, Y, and Z. These three axis can design most parts, but there are also 5-axis machines that move diagonally and at an angle. 

A 5-axis machine is able to produce just about any part that can be CNC machined. These machines are more expensive and require more experience to set up. Once they’re set up, it can machine more parts faster than a 3-axis machine. 

The CNC mill is sometimes used for finishing machining, such as adding a hole, angle, slot, or threading to a semi-finished part. Other parts can be milled from raw material to finished part. 

If you have more questions about CNC milling and turning, don’t hesitate to reach out to our team.

We have worked on thousands of custom projects in a range of industries. We are happy to help you pick the best machining process for your next project. 

Related content

Contact us

Talk with one of our team members to get a quote or if you have any questions. 

We would love to hear from you! Please fill out this form and we will get in touch with you shortly.
  • Max. file size: 256 MB.
Spex Logo

Phone: (585) 467-0520

Email: sales@spex1.com

Office:
85 Excel Drive
Rochester, NY 14621