What Is CNC Turning?

Did you know the global computer numerical control (CNC) machine tool market is projected to reach over $128 billion by 2028, according to Fortune Business Insights? This is a significant increase from where it stood in mid-2021, at $83.9 billion.

CNC machining has transformed the manufacturing industry, and it’s not slowing down anytime soon. This process makes it possible to produce parts with speed and accuracy that can’t be duplicated manually.

Within the CNC industry, there are many different techniques that can be used — one of them being CNC turning. Keep reading to learn all about this manufacturing process and what it’s used for.

CNC Turning Definition

In CNC turning, a chuck (or specialized clamp) holds bars of material and, as they are rotated, a tool is fed to the piece to remove material to create a specific shape. A turret, which holds a group of tools, is programmed to move along the work piece in three different axes of motion to shape the material according to the assigned specifications.

Image credit: Kirkstall Precision Engineering

Since CNC turning involves removing material from a work piece, it’s considered a “subtraction machining” process. It is done on a lathe machine, which can be used on all types of material, from wood to metal to plastic. It can also be done on a mill or a drill press.

Turning is primarily used to create cylindrical parts. It can be completed on the outside or the inside of a work piece, which is known as boring. The process can also be used to conduct various other operations, including:

• Grooving: Cuts grooves or creates narrow cavities in work pieces.
• Taper turning: Creates a gradually decreasing diameter in a cylindrical shape.
• Drilling: Produces round holes, which are typically for screws and bolts.
• Facing: Cuts a flat surface perpendicular to the axes of the milling cutter.
• Parting: Separates one part of the work piece from another.
• Knurling: Creates vertical, horizontal or crossing lines on the work piece.
• Threading: Makes grooves that can be screwed into other objects.

Turning Operation in CNC

CNC turning used to be done manually, but this proved to be very time consuming as it requires an operator to closely monitor the process. It also was more likely to produce errors.

Thanks to advancements in technology, turning is now done using a computer. In this process, an operator will write a computer program that specifies the necessary dimensions. This file is then transmitted to the lathe machine, which will control the cutting tool to produce the part. This process is much more accurate and efficient than the manual process.

So what exactly is CNC turning used for? In general, this process is ideal for large production runs with short lead times. It’s used to support a wide variety of industries, such as:

• The electrical industry
• Electrical discharge machining
• Woodworking
• Material fabrication
• Metal removing

CNC turning can create parts used by the automotive, medical, optical, aerospace and power industries, just to name a few.

The Difference Between CNC Turning and Milling

Another process commonly used in the CNC industry is milling. While milling has some similarities with turning, there are key differences.

In general, CNC turning tends to produce parts faster and more affordably than milling. Turning has a larger range of motion, so it’s ideal for creating more complex designs, especially in cylindrical parts. However, milling is better for conserving material.

Image credit: CNCVina

The CNC milling process works by removing material from the workpiece using a rotating, multi-point cutting tool and computerized controls. It’s best suited for small production runs and prototypes, and its production capabilities include thermal, mechanical, electrical and chemical applications.

In short, CNC turning uses a rotating part for cutting, while CNC milling utilizes a rotating multi-point tool. Both methods are used to support many of the same industries, so choosing one comes down to the specific project and resources available.

In some cases, turning and milling are used in conjunction. For example, a piece may start out with turning to create a general shape and later require milling for added features.

Train to Become a CNC Machinist in Just 36 Weeks

If the process of CNC turning and milling interests you, consider pursuing a career in the CNC industry. As mentioned, CNC machining supports a wide variety of industries, which can open the door to exciting career opportunities.

With the CNC Machining Technology program offered at NASCAR Technical Institute, you can train to become a CNC machinist in just 36 weeks.1

Created in conjunction with Roush Yates, a leading brand in the performance industry, this program is designed to equip you with the knowledge and hands-on experience needed to start your career. You’ll take courses on a variety of topics, including:

• CNC Basics
• Basic Machine Shop Skills
• Manual Machining Basics
• Interpreting Blueprints / Layout
• CNC Turning
• CNC Milling
• CAD and CAM

Classes start every six weeks at the NASCAR Tech campus in Mooresville, North Carolina. If pursuing your education requires you to relocate, NASCAR Tech offers housing assistance so you can find living arrangements in the area while you complete your training.

To learn more, visit our program page and request information to get in touch with an Admissions Representative today.

NASCAR Technical Institute Campuses That Offer CNC Training

• Mooresville, North Carolina