What is CNC Machining
The Ultimate Guid to CNC Machining

In the industry CNC machining is seen to be the essential technology, which accelerate the advancement of human history. You might wonder what CNC is, how it works, and something more about this technology. Now, let's dig out the basic knowledges of CNC machining, and after this article, you will get overall views of the technique.

Computer numerical control (CNC) is a manufacturing progress in which software are embedded to control the movement of tools and workpieces. It is generally applied in producing for metal and plastic parts. However, CNC machining is not only for machined parts. It is also excellent for makers to produce creative tools or models.

What is CNC machining?

CNC-computer numerical control is a machining process controlled by a computer. CNC produces parts precisely and quickly with complex geometries compared to manual machining. As CNC makes parts and models by machines, it reduces machining labour and improves productivity. Programming becomes essential for the operation of CNC as the operator needs to design the part at first in the software and transfer the data to the machines. CNC is one kind of automation that helps humans to produce faster and more precise. The CNC innovation is important to the modern industry production and it will be more important with the development of CNC technology.

How does CNC machining work?

Most CNC machines require software programs to run the process. To turn the design into a language machine that can understand and produce parts, CAM(Computer Aided Machining) is the essential system. First, you must create the software's Numerical Control (NC) codes and tool paths. Then the post-processing of the CAM converts tool paths to the machinery. The machinery starts production based on the precise design and data from the software.

CAM programming requires the operator to have knowledge and skills for running the machines. NC code is an essential and fundamental part to be talk at first. Compared to other ways to run a CNC cutting machine, NC code has to be the simple way to execute the instructions. The most popular NC language is ISO code(G-code) which could work on different machines, including Stoney CNC, FANUC CNC, and American Haas. There is no doubt that G code is widely used in CNC machining. It also provides you with a basic understanding you need for CNC machining.

History of CNC machining

In the 1940s, CNC came into people's sight as a modern mainstay of manufacturing and production when the first numerical control and machines emerged. After the 40s, the development of machines increases precision and efficiency.CNC has started to replace more people labors and increase productivity.

After almost 80 years of development, CNC machining has more definitions nowadays. It could turn 3D design files into a computer and produce models automatically by controlling the motion of tools. CNC machining has become more precise by controlling the cutting process axis and speed of rotation. With the continuous development of machining and software, CNC machining will become more potent in the coming future.

Benefits of CNC machining

No matter what industry they all can benefits from procise CNC machining. Making the part and component fast and accuracy

Efficient production

CNC can operate these on their fastest settings when working with milling machines to match increased demands. Compared to human labour, machines can work 24 hours without breaking. CNC can also produce accurate parts. It will reduce material waste and lower the cost. Once you set up the design and production setting, the machines will finish the rest. The human will be the supervisory role that monitors the whole production process.

High accuracy and low defects

Machines make fewer errors than humans. The machines can produce the exact model you design with accurate data from the software. The tight tolerances typically range from ±0.00508 mm to ±0.0127 mm. The size of a single hair is 0.016 to 0.05mm. Compared to hand-made, the CNC provides high accuracy, no doubt.

Lower the production cost

The CNC improves production efficiency and scalability and reduces the material lost. Also, the CNC saves energy consumption and reduce the risk of human accident. All in all, the CNC is the better option when it comes to modern production.

Easy Assembly

With CNC, employees can go to assemble the parts when the CNC machines make parts. As we know, the assembly lines are more effective in high production settings and require specialized skills that machines can not replace. Also, the high-precision turning of parts allows for the seamless fitting parts, and employees can flow easier without any disruption.

Less energy consumption

Human production might cause energy losses due to improper planning. But with CNC, they will cut down the energy loss by usurping resources like energy and labor if not necessary.

Improve personnel safety

During CNC production, there is much less human production during the process. It can reduce the risk to life and limb by isolating the machines from the human. The invention of CNC improves the safety of modern production and makes the workplace safer than before.

Types of CNC machines

In the CNC process, the CNC machines are the final place that brings design to reality. There are many CNC machines; today, let's walk through all these CNC machine types.

3-axis CNC machine

3-axis machines cut and trim materials along the XYZ plane. For parts without much depth and details cutting, 3 axes are widely used to produce the components. Besides that, it is also designed for: Automatic/interactive, operation Milling, slots Drilling holes and Cutting sharp edges.

4-axis CNC machine

Compared to 3-axis machines, 4-axis machines have one more rotary movement called the A axis. An axis could cut the material around the B axis. With an additional axis, the machines could flip over the workpiece automatically and remove extra material from both sides. It could be used for:Continuous cutting, Intermittent cutting ,Engraving curved surfaces.

5-axis CNC machine

5 Axis machines can select two to three rotational axes(A,B,C) to perform a 180° rotation around the X, Y, and Z axes. 5 Axis CNC machines are widely used in aerospace and automobile. It is designed for complex components production. 5axis machines could work all 5 sides, and it saves production time. But it requires more time in model preparation. When components require intricacy and precision in a shorter production time, 5-axis machining will be the best option. In the following cases 5-axis would be a better choice for production:

Complex geometrical parts

Boost productivity

Have higher quality finishes

cutting intricate details.

Types of CNC process

There are some different types of CNC machining processes in the pratices. The most common approaches are CNC milling, CNC turning and CNC EDM. To enhance the produtivity the mixed processes will be used, and then some parts may need post-processing, such as finishing, polishing, coating.

CNC milling

CNC milling is a process that manages the movement of multi-point cutting tools to move across the surface of the workpiece. CNC milling could achieve the desired shape and size by excessing the extra material.

CNC Turning

For axially symmetric parts and cylindrical-shaped workpieces, CNC turning could cut the material to the desired shape and size faster than milling and cost lower per unit.

CNC EDM

Electric discharge machining cut through the workpiece while submerged in a tank of deionized water for a workpiece made of conductive material. When the surface is difficult to cut, and milling cannot reach, EDM could help, in some cases for accurate making, you may need wire cut EDM . CNC EDM removes the extra material and produces the desired final geometry by creating an electric arc through the fluid.

Types of CNC materials

Now let's discover some popular materials used in CNC production, mainly are mental, wood and plastic. Each material kind has its advantages. Let's see why people choose it as raw material for CNC.

Metals

Mental could be made into a prototype, a production component. Some mental can be highly durable and harsh temperature environments up to 1668 degrees like titanium. Some are low-cost, like aluminium. If you want to make parts cool with the look of polished stainless steel at a reasonable price, you can choose zinc as your material. If you have a limited budget, aluminium is your best choices.In all,You could choose a different mental type depending on your need. Here are some mental materials:

Aluminium, Copper, Bronze for CNC machining Brass, Stainless steel for CNC machining Steel, Titanium, Zinc,

Plastics

Plastic is commonly seen in CNC production. Like ABS, it is easily machined and cost-effective. Plastic is also relatively straightforward for CNC machines. It is widely used in the medical, automotive, military, and defence Industries. You could choose what plastic material based on your need.

HDPE, Acetal (Delrin), Polypropylene, Polycarbonate, PEEK, PTFE-Teflon, PVC for CNC machining UHMW-PE, Nylon 6/6, Acrylic, ABS,

Wood

Wood is also a common material for CNC production. Compared to metal, Wood is easier to cut and it is the most popular material for CNC milling. Wood is commonly used for making artworks, furniture, prototypes, and others. Different wood material has their use. For instance, hardwood like ash wood will be great if you want to make high durability and quality furniture. If you don't have a big project budget, a softwood like cedar, or cypress might be a better option compared to hardwood. If you want to mill full-size 4*8 sheets for your project, engineered wood like MDF is what is needed. In all, you can choose different kinds of wood based on your demand and budget.

Surface finish for CNC machined parts

After the CNC finishes, many parts require additional processing to achieve a desired surface or property for cosmetic, corrosion resistance, wear resistance, or other purposes. Here are some types of processing we often see in CNC production.

Polishing

Polishing is the process of polishing surfaces based on your destination. The surface can be consistent on all sides of the part after the polishing. Polishing can be done by hand or by polishing equipment.

Powder coating

Powder coating spreads a powder-type paint to a component and then bakes the paint. It owns over 15% of the whole industrial finishing market. It should be noted that the powder coating does not provide an accurate surface process like CNC operations. It is essential to mask off some important areas during the powder coating. Your project has multiple powder coating options, from color to texture.

bead blast

Applying the tiny glass beads under high pressure to the surface of a component. By causing a light texturizing without damaging the part, the bead blast can help a matte-type texture. Bead blasting may or may not cause extra cost.

Anodizing

Anodizing is a wear-resistant coating. It is widely associated with aluminium parts and comes in many colors. Anodizing preserves the metal's natural luster, texture, and beauty. Since the layer is consistent and think-less than .002 inches thick, you need to consider the machine's marks underneath before anodizing.

The trends of CNC machining

With the constant development of CNC machining, there are some new trends are expected in future.

Increased use of robotics

The robotics for the CNC will be taught more about their intended operation with manual movements to reduce less human work during the process. The future robots for CNC will be more intelligent and work more closely and smartly with humans. The increased use and the revolution of robotics will also push the development of CNC and make CNC better used in health care, military, and food preparation industries.

loT

The development of loT-Internet of things increased the communication of machines, software, and big data. Companies can find the addressing issues based on the internet database they created, and machines can be more intelligent with the data support. Also, the factories can monitor CNC machine working processes easily and safely with the loT development. More loT CNC machines' comprehensive solutions might show up in the future market.

Industry and personal hobby

Nowadays, not only large companies can use CNC to improve supply chain agility and efficiency. If you like designing and producing as a personal maker, you can upload a model and make it. It has become more accessible than before.

Advances in CAD/CAM software

Many software has developed a lot. It is more user-friendly and powerful. Not only has the latest software improved efficiency and accuracy. It has become easier to learn and operate with innovative and standard workflow. For example, Easel software is web-based software. You can create a design and turn to the G code and even simulate it on the web. Easel also created many tutorial videos and keep making the web design user-friendly. Many software companies are working hard to reduce the essential long learning hours for the CNC software operation.

The expectation of CNC machining

With the development of CNC, people have more expectation about what CNC can do. Here are some expectations of future CNC machines.

More complex parts

People are expecting that CNC machines can handle more complex CNC parts such as parts that have special unique patterns. When the future CNC has more axes, it can handle more complex parts for sure.

Faster and easier data processing

CNC machine's data process takes time depending on the complexity of parts. Sometimes matching the CNC hardware and software is not easy to learn. With the development of software and CNC, future data processing might be faster and easier.

Less learning time for the machinists

People are expecting that future CNC will be easier for junior operators to create parts without much learning. With the original setting and the training of senior operators, junior operators can immediately start using the CNC machines without making errors.

Starting CNC machining projects wiht EXZELLENC

EXZELLENC offers professtional solution for your metal manufacturing with CNC machining services. we ensure our customers with best quality and low costs, which is essential for long-term business. In order to implement your project completely and successfully we are working flexbiblely, so that we both sides can achieve the best results. Say hello to us, and let's talk.