Most CNC machines use CAD and CAM software to fabricate precise and accurate components. However, the main challenge in modern manufacturing industries is understanding the operation of these machines. CNC turning and milling remain the commonest CNC machining processes manufacturers apply to fabricate various components.
While the turn-mill operations overlap, they apply distinct machining methods. Continue reading as we examine the differences between CNC turning and CNC milling and their applications to help you make an informed choice.
What is CNC Turning?
Turning is a popular form of CNC machining process. CNC turning basics comprise affixing suitable materials in a rotating chuck. At the same time, the cutting tools fed to the workpiece remove the material until the needed shape is formed. Generally, CNC lathes or turning centers apply in turning operations.
Before the advent of computer programs, manufacturers operated lathes by hand, making them more labor-intensive. Thus, the innovative development of Computer Numerical Control (CNC) uses pre-programmed software to automate various processes on suitable workpieces. They include drilling, boring, grooving, parting, facing, knurling, etc.
A CNC lathe comprises a chuck and multi-sized cutting tools. Before using the machine, the machinist must set the cutter’s speed, feed rate, depth, and other important instructions to get the desired shape component automatically. During the turning operations, the chuck helps hold the workpiece in place, while the cutting tools attached to a turret move toward the rotating workpiece to remove excess material where required.
Most manufacturers use CNC lathes with only one turret and apply suitable cutting tools individually to complete many projects on one side. In other cases, some experts also use turning centers with a main spindle and sub-spindle for more rapid operations. In this configuration, the main spindle moderately machines the material. It then gets directed to the sub-spindle to perfect the work on the other side of the desired component.
What is CNC Milling?
CNC milling basics involve using computer software to automate and control milling tools. It combines various processes such as face, angular, or plain milling to fabricate exact components from suitable materials.
A CNC mill comprises a vertical spindle and revolving head that contains a rotary cutter fed to the workpiece. During CNC milling operations, the mill holds the workpiece stationary on the machine bed. Then, the spinning multi-point cutting tools get fed to the workpiece’s surface to progressively remove excess materials in a controlled setup until almost any desired shape gets formed.
Furthermore, CNC mills are available in different configurations. They include the 3, 4, or 5-axis mills. While the traditional 3-axis CNC mill directs the cutting tool in three angles – X, Y, and Z, the modern 5-axis CNC milling machine enables the cutting tool to move in up to five directions.
Note that the higher the number of cutting angles or axes, the more the dimension of flexibility, enabling CNC mills to fabricate custom components with complex geometry and intricate details. That way, you’ll find that using the 5-axis machine is more expensive due to its flexible features, impacting the final cost of intricate milled components.
Milling vs. Turning: What are Differences?
The most significant difference between CNC milling and CNC turning lies in the movement of the cutting tool and workpiece. In CNC turning operations, the workpiece revolves or rotates at a set speed, whereas the cutting remains stationary. On the flip side, CNC milling involves holding the workpiece in a fixed position while the cutting tool spins around it to subtract excess materials.
Concisely, this variation in the cutting tool or workpiece movement reflects the differences in dimensions and shapes that each machining method can best produce. Below are some other notable differences between CNC turning and milling:
CNC turning uses a single-point cutting tool, while CNC milling processes use multi-point cutting tools.
CNC milling includes machining processes such as plain, angular, and face milling, while CNC turning includes machining operations such as grooving, boring, drilling, straight and taper turning, threading, and knurling.
CNC turning is best suited for producing components with axially symmetrical shapes. They include cylinders, disks, cones, and polygons. Meanwhile, CNC milling can produce components with both symmetrical and non-symmetrical shapes.
CNC turning is highly adaptable to many materials, including metals, plastics, and wood. On the contrary, CNC milling has more selective compatibility with raw materials. Therefore, experts usually use CNC milling for materials such as aluminum, stainless, carbon steel, titanium, and nylon.
Milling vs. Turning: When to Choose the Right One?
Even though CNC machines offer numerous advantages, manufacturers must examine the design requirements before settling on the CNC machining operation best fitted for each manufacturing project. If you are ever in doubt, an expert machinist can guide you in choosing the proper CNC machining process for your manufacturing project. Here are some useful tips to guide you in selecting the right machining process:
When to Choose CNC Milling?
CNC milling uses rotating cutting tools to subtract materials across a stationary workpiece. So, experts often choose CNC milling for manufacturing projects that do not require cylindrical components. That being said, you can apply CNC milling in machining flat or irregular surfaces. Additionally, you can best choose CNC milling for secondary finishing processes as it provides well-defined design features.
When to Choose CNC Turning?
CNC turning involves rotating the workpiece while the cutting tool makes contact to remove excess materials. For this reason, expert machinists select CNC turning for manufacturing projects that require cylindrical or round profiles. Moreover, the high-speed rotation and wide-ranging compatibility of CNC turning operations with different materials make it best suited for large production of tubular parts.
Mill vs. Lathe – Applications in Custom Part Fabrication
CNC mills and lathes apply in many machining operations across several industries today. They include electrical, woodworking and metalworking, automotive, medical, aerospace, motorcycle industries, etc. Check the application of CNC mills and CNC lathes in custom part fabrication below:
CNC Mill Applications
- Engine parts
- Medical instruments
- Water pumps, etc.
CNC Lathe Applications
- Round Shafts
- Ball Joints
- Flanges for beams and pipes, etc.
Require Milling vs. Turning: WayKen Can Handle Both of Them
CNC turning is typically used for parts with round features, while CNC milling is more suitable for other shapes. If you’re not sure which process to use, WayKen’s machining experts can help you choose the right CNC machining service for your project.
In addition, in some cases, CNC milling and CNC turning can be combined to get the best results. So, whether your project requires turning or milling, with our extensive machining experience, your needs can be met to a high standard. Get a quote today and discuss the details with our engineers.
CNC machines have become a staple in many manufacturing companies. These computerized machines incorporate pre-programmed software to automate machining operations, thus making most manufacturing processes more efficient, faster, and precise.
CNC milling and turning remain the most popular CNC manufacturing operations. Even though both processes have certain CNC similarities, there’s much more to their machining methods than meets the eye. Thus, this article examines the differences between CNC turning and milling and their application in fabricating custom components.
Which is better? A lathe or mill?
This mainly depends on your manufacturing project. A CNC lathe is most suitable for the continuous fabrication of cylindrical components due to its higher production efficiency and performance. Conversely, a CNC mill will outperform a lathe when applying finishing features to a custom-designed component.
Is turning cheaper than milling?
To a large extent, manufacturers tend to fabricate turned products at a much lower cost compared to milled components. This is because CNC turning procedures allow the efficient production of various parts within a short period, thus minimizing additional costs sustained due to manufacturing errors.
What are the similarities between milling and turning?
-CNC milling and turning to use computer technology to automate and control machine tools. Therefore, they both minimize human errors to deliver the low volume of quality products within a short period.
-Both processes use subtractive manufacturing techniques.
-Both machining operations generate heat and often require fluids to reduce the heat.
-Milling and turning operations are compatible with workpieces like aluminum, titanium, steel, copper, and an array of thermoplastics.