In the modern manufacturing industry, the distance between the CAD model on the computer screen to the physical parts in hand determines whether a product has the ability to seize market opportunities. When you’re faced with the high cost of mold opening from injection molds and the limitations of 3D printing in terms of material strength, CNC machining offers you a unique “fast lane”.
With CNC machining services, you cannot only use real production-grade materials, but also achieve a seamless transition from rapid prototyping to low-volume production in a very short time. If you are still looking for a manufacturing solution that combines speed, precision and material diversity, then an deep understanding of CNC machining will be the first step to optimize your purchasing decision.
What is CNC Machining?
CNC machining is a subtractive manufacturing method, CNC stands for Computer Numerical Control. The process is to control the machine tools through computer programs, and use the cutting tool to cut and shape metal, plastic and other materials, so as to produce high-precision finished parts. It contains many process types, including CNC milling, CNC turning, etc. You can choose the best method according to different parts manufacturing needs. In addition, common CNC equipment includes CNC lathes, machining centers, five-axis machine tools, etc.
It can be said that it is precisely because of the emergence of CNC machining that the requirements for high precision, high strength and high efficiency have been perfectly balanced.
Types Of CNC Machining Processes
CNC is not a single individual, on the contrary, it has a variety of precision manufacturing methods. CNC machining methods can be divided into several categories based on cutting methods and workpiece movement paths. Next, I will introduce them to you in detail, so that you can gain an in-depth understanding of the capabilities of these machining processes.
1. CNC Milling
CNC Milling can be said to be the most common CNC processing technology. For example, our company has provided the most CNC milling services to customers over the years. This process mainly involves the workpiece being firmly fixed on the workbench, while the high-speed rotating cutting tool (milling cutter) moves on the X, Y, and Z axes, cutting off excess material on the workpiece like engraving, thereby gradually manufacturing the finished part. Here comes the key point. The core point of this process is the “number of axes”. The following two multi-axis machining methods should also be frequently encountered in your daily work.
- 3-Axis Milling: The most basic form of CNC milling.The tool in this process can only move up and down, left and right, and forward and backward. This means that 3-axis CNC machining are only suitable for machining flat structures or shallow grooves.The advantage is that it is cheap, but once there is a hole in the side of the part, it needs to be manually re-turned and clamped, which will undoubtedly introduce cumulative errors.
- 5-Axis Machining: This is the standard configuration for high-end manufacturing. In addition to the basic XYZ movements mentioned above, the table or spindle can also rotate and oscillate. 5-axis machining services are ideal for producing high-precision, complex components for you.
In addition, the parts most suitable for CNC milling manufacturing include box parts, complex brackets, aerospace components with curved surfaces, etc.
2. CNC Turning
Contrary to the working method of CNC milling with tool movement and workpiece not moving, CNC turning is precisely when the knife does not move and the workpiece moves. The working principle of CNC turning is that the workpiece rotates at high speed on the spindle, while the cutting tool is fixed, and the tool will slowly move to touch the rotating surface, peeling off the material on the workpiece like peeling an apple.
At the same time, traditional turning can only make cylinders. But in modern manufacturing, we use turning-milling centers more. This machine is equipped with a powered turret, so it can also perform milling operations while turning.In other words, the machining operations that were previously completed on two machines can be done on this one. This can be said to greatly shorten the supply chain process and reduce the risk of bumps in the flow of parts.
As for the most suitable parts for CNC turning services? For example, shafts, pins, bolts, flanges, etc., these parts with cylindrical characteristics are very suitable, and there must be one of them.
3. EDM
The tool can’t cut the material, or is the part too complex to handle? At this time you need to use the EDM machining. The process is a non-contact process. It mainly uses the high-frequency electric sparks generated between the electrode and the workpiece to gradually remove the material. To simplify, you can imagine it as carving metal with little lightning.
- Wire EDM: The specific principle is that a small discharge gap is formed between the workpiece and the wire electrode in the processing fluid (generally deionized water), and the pulse current generates a plasma channel, which instantaneously erodes and removes the material.
- Sinker EDM: There is a small gap between the formed electrode and the workpiece in the insulating medium (commonly used EDM oil), and the pulse discharge is used to erode the material layer by layer to form the same shape as the electrode.
You have to know that because CNC milling cutters are round, they can never mill perfect right-angled internal corners (there will be R angles). And EDM is the only solution to this problem. Therefore, EDM services are often used for injection mold manufacturing, deep and narrow groove structures, etc.
4. CNC Grinding
This is a finishing process in the CNC machining process. The high-speed rotating grinding wheel performs micro-cutting on the workpiece surface, thereby improving the part quality. After all, after CNC milling, there will usually be visible machining marks on the component surface. Therefore, if you need a mirror-level finish or a roughness below Ra 0.8, then the CNC grinding step is necessary.
Another thing worth noting is that grinding is expensive and time-consuming, if you don’t need too high surface quality, then don’t mark too high surface finish requirements on the drawings, which will significantly increase your cost.
5. CNC Drilling
As the name suggests, this process is used to drill holes in components. The principle is to use a drill bit to penetrate the material vertically downward. Although it may seem simple, in industrial production, CNC drilling is one of the large sciences. It’s not just drilling a hole. It also includes processes like reaming for hole diameter accuracy, tapping to create threads in the workpiece, and gun drilling-drilling a hole with a depth of more than 10 times the diameter along the long axis without deflection.
So, any part that requires screw holes, locating holes, or fluid channels can be achieved by CNC drilling services.
6. CNC Lathe
CNC lathe is a high-precision machining equipment with a computer numerical control system that automatically controls the tool for rotational cutting, and is mainly used for the efficient processing of the outer circle, inner hole, end face, thread and other parts of various shafts and disk parts. Its working principle is to receive program instructions through the CNC system and automatically control the movement of the spindle, tool holder, feed system and other components to achieve high-precision cutting of the workpiece.
Moreover, constant linear speed control is an advanced function of CNC lathe machining. As the tool cuts from the outer circle to the center of the circle, the diameter of the workpiece becomes smaller. To maintain a constant cutting speed, the spindle automatically accelerates. In this way, the surface finish of the end face is consistent, and there will be no difference in the depth of the inner and outer rings.
How Does CNC Machining Work?
You must also want to know about the entire CNC processing workflow, and I will explain it to you in detail next.
1. Design and Data Preparation
First of all, you need to model the part with some software such as CAD and define the dimension, tolerance, material, and other important surfaces for the component. And at this stage, you also have to consider “manufacturability” (DFM).
2. CAM Programming and Tool Paths
Because CNC doesn’t understand a 3D model, it only works according to coordinate codes, so CAM software is needed at this time. In the CAM software, you must select the machining strategy (roughing, semi-finishing, finishing, etc.) and generate the toolpath. Afterwards, the software will generates these strategies into G-Code, a machine-recognizable language that allows the machine to understand how to machine.
This step is very important, good programming at this stage can save you a lot of money and it will also determine the efficiency and surface quality of your machining.
3. Machine Preparation
After setting the machine language and processing path, you need to do the preparation work of the machine tool. The first thing to do is to select and clamp the tool (end mill, ball cutter, drill, etc.) and tool holder, and measure the length and diameter of the tool. Secondly, set the workpiece coordinate system (zero point) and do the tool setting and alignment datum. Thirdly, you also need to pay attention to the setting of the safety plane and collision avoidance, and dry running or simulation is performed to ensure that the path is safe.
4. The Execution – CNC
Next comes the formal machining process. Before machining, you need to fix the raw material (metal or plastic block) on the workbench of the machine tool, load the G code, and press the start button. Then the machine tool will drive each axis (X/Y/Z + possible A/B rotation axis) to perform interpolation motion under the instructions of G-code. During this period, the high-speed rotating spindle will drive the tool (milling) or the workpiece (turning), cutting into the material with extremely high force, and gradually completing the processing of the entire part.
The other thing you should know is closed-loop control. This is the core secret of CNC. In fact, there is a feedback system inside the machine, which monitors the position of the tool in real time. If the tool deviates from the instruction by even 0.001mm, the system will automatically correct it immediately.At the same time, during the entire cutting process, the coolant is continuously sprayed, which not only reduces the temperature to prevent deformation, but also washes away the cut metal chips.
5. Inspection and Post-Processing
The final step is the familiar testing and post-processing step. In this step, inspectors need to use tools such as calipers, micrometers, and coordinates (CMM) to carefully inspect the parts, and also conduct targeted tool evaluations on the surface and shape to ensure that they meet the production requirements.
In addition, it also needs to perform various post-processing on parts with special requirements, such as deburring, cleaning, heat treatment, surface treatment, etc.
In this way, the entire part machining process is considered complete.
What are the Advantages of CNC Machining?
After all that has been said, you must be very curious about what advantages CNC machining actually has?
1. Precision & Accuracy
CNC machining can manufacture a variety of high-precision and high-quality parts for you, greatly reducing their tolerances. This is also the core competitiveness of CNC.
High-end CNC machine tools can achieve a processing accuracy of ±0.005mm or even higher for you, which means that the finished parts can fit perfectly when assembled. At the same time, during the machining process, as long as the program is written correctly, the machine will strictly execute the instructions, reducing various errors caused by human intervention. This is one of the reasons why CNC machining has obvious advantages over manual processing.
2. Efficiency & Speed
High efficiency is another outstanding aspect of CNC machining. I believe that manufacturers need to face a large number of product order manufacturing requirements every day. How to complete the delivery of goods within the delivery date and ensure quality, then efficiency is the key. CNC can exactly meet this requirement. It greatly releases productivity and allows factories to operate 24 hours a day.
As long as it is matched with an automatic loading and unloading system, CNC machines can achieve completely autonomous production. Today’s advanced 5-axis machines also allow tools to approach the workpiece from all angles. This means that even complex geometries such as turbine blades can be milled in one clamping operation, without workers having to stop and adjust positions again and again.
3. Consistency
Mass production of many identical parts can only be done by CNC. This means that there is little difference in size and quality between the 1st and 10,000th parts. This is important for those industries that assemble on a large assembly line.
4. Scalability
CNC machining is very suitable for rapid prototyping service. You can use this process to create corresponding models. During this period, if modifications are needed, you only need to change a few lines of code on the computer, and a new version of the part can be produced in a few minutes. In addition, CNC machining does not require mold costs like mold opening, which is quite cost-effective and faster for small and medium-sized batch production,and the speed is faster.
5. Strong Processing Capability for Complex Parts
I believe you all have manufacturing needs for complex structural parts, especially for manufacturers with custom metal machining and custom CNC component. CNC machining can process complex curved surfaces, special-shaped parts and structures that are difficult to complete by hand. It also supports multi-axis linkage and has a wide processing space. In other words, CNC can cover the processing needs of planes, slots, holes, cavities, free-form surfaces, etc., and it can also cooperate with EDM, grinding, surface finish and other processes to achieve acute internal angles, deep cavities and ultra-precision surfaces.
6. Material and Cost Savings
Another advantage that everyone likes is that CNC machining can save materials and costs well. This process can precisely control the machining process and reduce material waste. At the same time, due to the high degree of automation of machine tools, this also reduces labor costs.
Application of CNC Machining
CNC machining has now been widely used in many industries, and you can use this high-end manufacturing method to make a variety of parts.
1. Automotive
Automotive industry is one of the biggest application fields of CNC machining. It ranges from R&D to mass production of prototypes in all areas. From Power system like cylinder block, cylinder head to suspended gears and shaft components, you can produce all by CNC machining.
2. Aerospace
Aerospace field has extremely high requirements for the precision of machining, extremely high requirements for the strength of materials, and CNC machining can meet these requirements and produce high precision parts. Engine parts, fuselage structural parts, interior components, and many others can be made.
3. Electrical Industry
CNC machining can produce high-precision, consistent components for electronic devices and is very efficient.
4. Medical
The medical field has extremely high requirements for cleanliness, biocompatibility and tiny size. CNC machining is capable of processing special medical grade materials. Medical equipment such as human implants and surgical instruments can be made using CNC machining.
5. Industrial & Tooling
CNC can also produce tools used to make other products. For example, molds used for injection molding and auxiliary tools used to fix products on factory assembly lines.
6. Woodworking Industry
CNC can be used to take on repetitive, heavy and high-precision jobs, greatly reducing the machining time of wooden components and freeing up carpenters to focus on design, material selection and final finishing.
What Materials Can Be used in CNC Machining?
Are you curious about which materials can be processed by CNC machining? Don’t worry, I will explain them one by one next.
1. Metal
- Aluminum: Aluminum is the most commonly It is light in weight, dissipates heat well, cuts easily, and aluminum is also a material that can be surface-treated, such as anodizing.
- Stainless Steel: Stainless steel has the characteristics of high strength, corrosion resistance, and good gloss. Therefore, you can see stainless steel parts used in many industries. However, compared to aluminum, it is more difficult to process and more tools are needed.
- Steel: Steel is valuable because it is cheap and strong, and there are various types for you to choose from. But in the process of custom steel machining, you need to carry out anti-rust treatment.
- Brass: Brass has beautiful appearance and excellent cutting performance, so it is often used in valves and decorations.
- Copper: Copper has a very good electrical conductivity, so it can be used in electrodes, heat sinks, etc.
- Titanium: Titanium is generally more expensive, but its strength-to-weight ratio is extremely high, and it also has the characteristics of high temperature resistance and good biocompatibility. Therefore, in custom titanium machining, it is often used in aerospace and implantable medical devices and other fields.
2. Plastic
- ABS: ABS is the most common general-purpose plastic, it is cheap and has good impact resistance, so it is often used to make prototypes and shells.
- Nylon: Nylon is extremely wear-resistant, has excellent toughness and self-lubricating, so it is used to make gears, bearings and other components.
- POM : POM material has high hardness and excellent dimensional stability, making it one of the most suitable plastics for CNC machining, with a very smooth cut surface. In POM machining services, it can be used to make precision mechanical parts, snaps, and other components
- PEEK: PEEK is a material that can be used as a metal substitute. The reason why PEEK can be used as a metal substitute is that the material has high temperature resistance, chemical corrosion resistance, and high strength. PEEK can be used to make parts for extreme environments. But the material is very expensive.
- Polycarbonate: Polycarbonate is highly transparent, much like glass, but much tougher and less likely to break. Therefore, this material is also often used as transparent windows, protective covers, etc.
3. Others
- Wood: There are many types of wood, but they can all be made into various furniture and mold models through CNC machining.
- Foam: With CNC machining, you can make foam into packaging linings or the core of large sculptures.
- Composites: Carbon fiber plate, fiberglass sheet
Leading CNC Machining Technologies For Complex Design
Having said all the basic aspects above, let’s talk about the current leading technology in the CNC machining industry. Understanding and mastering these technologies can greatly improve your capabilities while also promoting the overall efficiency and productivity of your factory.
1. Simultaneous 5-Axis Machining
The emergence of 5-axis CNC machining has solved the problem of handling complex geometries in the machining industry. It adds two rotation axes (A-axis and B-axis) based on the traditional 3-axis X, Y, and Z moving axes. These five axes can be closely linked to make the tool and the workpiece move in five directions at the same time. Therefore, components with complex curved surfaces such as turbine blades and propellers can be cut into perfect streamlines using five-axis machining services.
On the other hand, the machine can automatically rotate the workpiece to process the 5 sides. The worker doesn’t have to manually remove the part and turn it over, which greatly reduces the human intervention error. At the same time, the tool can also be tilted to extend into deep pits or dead corners to prevent the tool handle from hitting the workpiece, thus completing processing tasks that were difficult to achieve in the past.
Now, according to a report by SME, an international manufacturing research organization, 5-axis CNC has become the standard equipment in aerospace and precision medical manufacturing, greatly improving the consistency and production efficiency of parts.
2. Mill-Turn / Multitasking
The ability to complete multiple processes at one time is perfect for those of you who are now pursuing efficiency, and this is Mill-Turn. It integrates turning, milling, drilling, tapping and other processing capabilities into one, and can complete multi-process processing of complex parts in a single clamping. Its key role is to eliminate the cumulative errors brought about by the multiple clamping of the workpiece and reduce the production cycle.
So how does Mill-Turn work? In short, within a machine, the workpiece can be rotated at high speed for turning, while the machine is also equipped with a power turret so that the rotating workpiece can be side-drilled, milled plane or engraved.This excellent machining capability can well solve machining problems such as asymmetrical rotary bodies and extremely high coaxiality.
If you need a machine that combines the advantages of efficiency, flexibility, and lean production, then Mill-Turn must be your best choice.
3. Intelligent and automated CNC machining system
Intelligence and automation are the two development trends of modern manufacturing. The intelligent CNC system integrates CAD/CAM automatic programming, online measurement and compensation, tool management, remote monitoring and other functions, realizing the digitalization and intelligence of the entire process from design to manufacturing. In other words, on a highly intelligent production line, the equipment can automatically load and unload the materials, and the robots will also come to the side to assist in processing, which will also further improve the factory’s unmanned production ability.
Today, the world’s leading manufacturing companies such as Siemens and DMG MORI have adopted intelligent CNC systems as their core competitiveness and have obtained multiple international certifications.
4. Hybrid Manufacturing
Hybrid manufacturing is also a trend in current development. It is an organic combination of 3D printing (additive manufacturing) and CNC machining (subtractive manufacturing). It first quickly forms complex structures through additive manufacturing, and then uses CNC to accurately process key surfaces and sizes to achieve the best unity of structural complexity and accuracy. For example, the complex cooling channels inside the rocket engine nozzle can’t be drilled only with CNC, and the surface is too rough if only 3D printing is used. Hybrid manufacturing perfectly solves this problem.
It can be said that hybrid manufacturing is the development direction of high-end manufacturing in the future, and it has now been industrialized in developed countries such as Europe, the United States, and Japan.
5. Swiss-Type Machining
I believe that some of you also have needs for micro-precision parts, and this swiss-type machining can just complete such demanding manufacturing tasks. Its working principle is that the cutting tool of the processing equipment does not move and the workpiece moves back and forth in the guide sleeve. It uses super-hard micro-cutting tools and high-rigidity machine tools to achieve sub-micron size control.
Nowadays, many electronic components, such as mobile phone camera modules, micro connectors, etc., are increasingly developing in the micro direction. These components require high-precision micro-machining equipment for CNC machining.
Future Trends in CNC Machining
1. AI-Driven Adaptive Machining
This is the most likely development situation at present. The current CNC still operates strictly according to G code, but the CNC of the future will have a “brain”.
For now, we still look at the data to artificially adjust the machine’s commands. But in the near future, machines will monitor spindle load, vibration, and temperature in real time through sensors. If the AI senses that the tool has cut to the hard point of the material, it will automatically reduce the feed rate in milliseconds to protect the tool; after cutting, it will automatically accelerate.
Another is that in the future CAM software will be generative AI, you put in a part model, the software will automatically analyze the best clamping method and toolpath, greatly reducing programmer experience.
2. Manufacturing as a Service
The business model of the CNC industry is undergoing a transformation. Now, cloud service platforms like our DSR are emerging. The engineer only needs to upload the CAD drawing to this platform, the AI can directly quote, and then automatically assign orders to CNC workshops in the global network with spare capacity.
At the same time, under this development trend, small CNC workshops can also receive large global orders. Large companies no longer need to build huge factories themselves, and the supply chain has become extremely flexible.
3. Automation 2.0
I have mentioned some above. In fact, if you read the news, you will know that the world is currently vigorously developing robots, such as Unitree H1/G1 of China’s Yushu Technology, Optimus Gen 2 owned by Musk’s Tesla, etc. These humanoid robots have started to behave like humans and can move their hands and feet flexibly, so these robots will likely enter our manufacturing industry in the future.
You should be aware that these robots are safe, easy to program, and can work side by side with humans. They can be used for clamping, cleaning, deburring, and other boring work, so people can spend more time on quality inspection and process optimization. In addition, combined with an automatic pallet changer (APC) and a central tool magazine, the factory of the future will truly operate unattended 24/7.
Summary
Well, the above is all I want to introduce. It can be said that CNC machining has played a crucial role in modern manufacturing. It can help us process different drawing models into high-precision components, and the entire machining process does not require human intervention, fully automated operation, and efficiency is greatly improved.Of course, as a CNC machining manufacturer serving more than 500 customers around the world, our DSR company can provide you with an excellent enough service experience, hurry up and contact us!
FAQ
Q1: What materials cannot be CNC machined?
A: Very soft and elastic materials (such as some rubber and silicone), very brittle and fragile materials (such as some ceramics and glass), and some composite materials (such as carbon fiber plate with very strong fiber directionality).
Q2: What is the biggest disadvantage of using CNC?
A: The biggest disadvantage of CNC machining is the high cost. Buying high-end CNC equipment, supporting software, and employee training all need large capital investment. In addition, the subsequent operating expenses such as equipment maintenance, tool replacement and system upgrades are also relatively high.
Q3: How much does CNC machining cost?
A: The price of CNC machining is highly variable. It depends on the number of variables such as part complexity, material, size, processing accuracy, and batch size. In general, the single-piece processing price of simple aluminum alloy or plastic parts may be 10 to 50 US dollars, and the unit price of parts with complex structure, high precision, or difficult to process materials may be as high as 50 to several hundred US dollars or more.
Q4: Can a CNC cut aluminum?
A: CNC machine tools can completely cut aluminum. Aluminum alloy is one of the most commonly used materials for CNC machining. Aluminum has good machinability, moderate strength and light weight. CNC equipment can accurately and efficiently complete various cutting, drilling and milling processes of aluminum parts. The processed surface has a high finish and the dimensional accuracy is easy to ensure.
Q5: Will CNC machinists be replaced by AI?
A: Although AI is used in more and more ways in the manufacturing industry to help with programming, optimize process flow, and even carry out automatic operation, CNC technicians cannot be completely replaced by artificial intelligence. CNC processing includes complex process judgment, exception handling, equipment maintenance, quality control, and so on, which requires a wealth of experience and practical operation capability.
Q6: What are the CNC Machining Services Available?
A: CNC machining services have a wide range of varieties, including many links from preliminary design to the production of finished products. Basic processing technologies that are often provided as CNC machining services include CNC milling, CNC turning, CNC drilling, CNC engraving, CNC cutting, etc. More high-end CNC machining services include multi-axis complex parts processing, prototype production, small batch customized production, precision parts processing, mold manufacturing, etc. Our DSR company can provide these high-quality services to you in need.
Q7: What are the Limitations of CNC Machining?
A: You should also know that CNC machining has certain disadvantages. Firstly, CNC machines are difficult to complete for parts with extremely complex structures or internal space. Secondly, some materials with high hardness, ultra-brittleness, or high elasticity are not suitable for CNC machining, which is easy to cause tool damage or machining failure. In addition, CNC machining has higher initial investment and maintenance costs.Finally, CNC programming and operation need professional technicians, and complex processes have long development cycles.
Q8: What is the Environmental Impact of CNC Machining?
A: The impact of CNC machining on the environment is mainly reflected in energy consumption, material waste and waste disposal.
Q9: What are the leading CNC machining software options?
A: CNC machining software is divided into CAM software and CNC control system software. The most mainstream choices for CAM software currently include Mastercam, Fusion 360, SolidWorks CAM, Siemens NX CAM, and Hypermill. Control systems include Fanuc, Siemens 840D, and Heidenhain.
Q10: What is CNC machining in simple terms?
A: Simply put, CNC machining is a process in which a computer controls a machine to cut materials instead of a human operator.
Why choose our DSR CNC machining services?
DSR Company is a CNC machining manufacturer with 14 years of experience. Our company can provide you with a series of customized processing services such as CNC milling and CNC turning mentioned above. Now we have established a partnership with senior material suppliers to supply us with excellent raw materials. In addition, we have a team of professional engineers who can provide you with reasonable solutions for your needs, which is very cost-effective. At the same time, our factory is equipped with complete production and quality inspection equipment, which can mass-produce various kinds of parts for you. I believe you will be very satisfied with the parts after you receive the delivery!
