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When it comes to precision manufacturing, you’ll often encounter two crucial processes─ CNC milling and CNC turning. Knowing the variations among these methods can assist you to optimize production, make better quality products and decrease cost. So let’s explore how these two techniques are different.
What is CNC Milling?
In CNC milling, you will use computer controlled tools to cut or shape material on a fixed workpiece. Shaping the material is usually made with a cutting tool which is spinning at high speed along many axes (X, Y, and Z) to cut the material. This is a very handy method to generate intricate parts, flat surfaces and angular cuts. CNC milling can be applied to a broad variety of materials from metals to composites to plastics.
What is CNC Turning?
On the other hand, in CNC turning, a workpiece is rotated and cutting tool is stationary. Such a process is perfect for producing round or symmetrical components such as shafts, pins and bolts. In this process the workpiece is spun on a lathe and material is removed by a computer controlled cutting tool. This is a high efficiency, high precision method and it works with different materials such as metals, plastics, etc.
Main Differences Between CNC Milling and CNC Turning
1. Working Process
CNC milling is a way of material removal which uses a spinning cutting tool to remove material out of a stationary workpiece. During milling, the machine’s spindle, which holds the tool, moves on multiple axes to make complicated shapes. Due to this versatility, different features, such as contour, flat surface and pocket can be produced.
Whereas CNC turning has a workpiece that rotates and a cutting tool that does not. Workpiece is clamped in a chuck on a lathe and spun at fast speed. The cutting tool shapes the workpiece to required shape by moving along the depth and length of workpiece.
2. Tool Movement and Operation
Cutting tool moves in three axes (X, Y and Z) at fast speed in milling. With this multi axis movement you can create complex features and shapes. Depending on the operation, end mills, drills, face mills and other such tools are used in milling.
Operation of turning is characterized by linear movement of a tool along the diameter of the rotating workpiece. The cutting tool will most usually be a single point cutting tool, i.e. a lathe tool, which removes material by continuous rotation. This is a particularly good setup to make symmetrical and cylindrical parts.
3. Types of Parts Produced
CNC milling is a great way to create parts that have non rotational features and complicated geometries. It’s an ideal way to make components with complicated features, uneven shapes and flat faces. Milled parts’ examples are engine blocks, aerospace parts and customized furniture parts.
CNC turning, however, focuses on axially symmetrical and cylindrical parts. It is perfect for manufacturing components such as rods, shafts and pins where the part geometry is around a single axis. Other turning operations including taper turning and threading allow you to create features, like grooves, tapers and threads into cylindrical workpieces.
4. Surface Finish and Tolerances
Milling give extraordinary surface finishes for complex or flat nonrotational parts. You can achieve very strict tolerances — in the ±0.005 inches range and even better. That’s why It’s suitable for applications that need very smooth finishes and greater precision on complicated geometries.
Turning also creates superior surface finishes but is only possible for cylindrical parts, which is because of the continuous rotation of work piece. It offers high accuracy of concentricity and diameter, thus suitable to make rods, shafts and other round parts that need good accuracy
5. Speed and Precision
Milling machines provide high precision to an accuracy of microns. That’s why they are important for industries such as electronics and aerospace in which precision is a must. But the complicated nature of parts produced by milling makes it slightly slower than turning.
In general, CNC turning is faster than milling in the making of symmetrical parts. It’s great at producing greatly accurate cylindrical components but it can’t compete with milling when it comes to intricate design. Similar to milling, turning can also achieve tolerances around ±0.005 inches.
Applications of CNC Turning and CNC Milling
CNC milling and turning are both important in many fields. Distinct applications for these machining processes are based on the special capabilities of these machining processes.
CNC Milling’s Applications
CNC milling is good for making complex geometries with tight tolerances. This process finds use in many key areas:
- Aerospace: Often the structural components, engine parts and turbine blades for aircraft are milled.
- Automotive: Automotive components such as engine blocks, transmission cases and specialised tooling are made by milling machines.
- Medical Devices: CNC mills turn out implants, prosthetics and surgical tools for medical use.
- Prototyping: CNC milling is commonly used in rapid prototyping to create functional prototype and detailed model before full production.
CNC Turning’s Applications
CNC turning is also the go to method to proficiently manufacture round parts. A few of its primary application areas include:
- General Manufacturing: Turning produces fasteners, bolts, screws, fittings and many other round components.
- Medical Field: The CNC turning makes medical precision parts such as catheters, needles and syringes.
- Automotive Industry: Shafts, axles and other cylindrical car parts are mostly turned.
- Aerospace Sector: Turning is leveraged in aerospace as well, in engine components and landing gear, where exact tolerances are needed.
CNC Milling Vs. CNC Turning – When to Use Which?
The choice between CNC milling and turning depends on your production quantity, part’s design and distinct features.
When to Opt for CNC Milling
CNC milling is the go to process for parts with complex detailing and intricate geometries. It also does great work when it comes to making non rotational parts that need features like holes, pockets, contours or slots. It is particularly helpful when making custom aerospace parts, engine blocks or transmission parts.
CNC milling is flexible and versatile and it offers you the possibility of working on multiple axes and with so many materials. And that is why it can be used to make part with very complicated designs.
When to Select CNC Turning
CNC turning is your best bet when you need accurate conical or cylindrical parts. This process also shines in terms of producing simple contours or uniform diameters. For manufacturing fasteners, tubes or shafts you’ll want to use CNC turning.
Turning is particularly useful when your project requires symmetrical parts with exact roundness. So, it’s invaluable in applications that need rotational symmetry in medical and automotive parts.
Hybrid Approach to CNC turning and CNC Milling
With turn mill machines, you have a very powerful hybrid way of doing both CNC turning and milling. These devices consist of a rotating chuck for turning operations and milling spindles with multi axis movement capability.
When performing turning operations, you will see the workpiece mounted on the chuck and not moving, whereas the stationary cutting tools do their cutting job. For milling, the process changes – Rotating cutting tools move around the workpiece and make complicated features whereas the workpiece remains still. It allows you to do prismatic and cylindrical details on one part without switching it between machines.
If you choose this method, setup times will be cut way down and your machining process will be more efficient and accurate. When components require both intricate milled features and rotational symmetry, turn mill machines prove to be extraordinary useful.
Conclusion
In short, it’s important to know the distinctions between CNC milling and turning to choose the right process for your project. Each method brings unique strengths to the table – Milling is great for making complex, non cylindrical shapes and turning is best choice for cylindrical parts.
If you need dependable, high quality CNC machining services, do consider Richconn. At competitive rates we provide advanced turning and milling services.
FAQs
Which is more cost effective? CNC milling or CNC turning?
It depends on your specific requirements. When you need to make a lot of cylindrical parts, CNC turning is the way to go. But if you require complex parts with multiple features CNC milling will give you much better value for your money.
How is CNC milling better than CNC turning?
CNC milling surpass CNC turning when it comes to making non rotational parts, intricate features and complex shapes.
What are the things you should consider while finding a reliable CNC milling and turning service provider?
If you are looking for a service provider, look for companies with up to date equipment, a good reputation and outstanding expertise in CNC milling and turning. You must take into consideration the quality assurance measures, turnaround time and industry certifications that are relevant to it.
