A Comprehensive Explanation of CNC Precision Machining
Have you ever noticed metal implants in the human body or complex engine parts in cars and airplanes? How are they formed into such precise shapes? It’s all thanks to CNC precision machining. CNC precision machining parts go through a complex manufacturing process.
The journey of these finely shaped custom parts begins with manufacturing, where CNC machining companies transform raw materials into products we use every day. Due to the increasing demand for more precise parts, CNC precision machining services are in high demand. These companies use advanced precision technology.
This advanced capability of computer numerical control machines is in the micron or even nanometer range. The development of miniaturized components in various fields is now possible. The main beneficiaries of this development are:
- Medical devices
- Electronics,
- Micro-Mechanical Systems (MEMS)
1.What is CNC Precision Machining?
CNC precision machining is a special form of manufacturing that uses CNC technology and high-precision CAD models to create parts with very tight tolerances. Beginners usually don’t understand the concept of tolerances. Let’s explain it in simple language. In traditional CNC machining CAD designs, it is difficult to meet dimensional accuracy.
On the other hand, in high-precision CNC machining, dimensional accuracy becomes the primary choice. For example, in traditional CNC machining, the tolerance is a few hundredths of a millimeter, but in CNC precision machining, the tolerance can be as small as one micron. This is equivalent to the width of a human hair.
Examples of CNC precision machining parts
- Surgical instruments
- Rocket engine components
- Joint replacements
2.What is the difference between CNC machining and precision machining?
Compared with traditional CNC machining, CNC precision machining has tighter tolerances. In addition, this method meets high-level dimensional requirements. Deviations are extremely small. Manufacturing CNC precision machining parts requires high precision, precision tools, and impeccable programming skills.
Likewise, precision machining provides smoother surfaces compared to traditional machining methods. However, CNC precision machining usually incurs higher costs due to maintaining quality standards.
CNC precision machining is different from traditional machining in many ways, such as:
| Features | CNC Machining | Precision CNC Machining |
| Focus | General – purpose machining | Manufacturing custom with extremely tight tolerances |
| Tolerance Level | Broader range, typically in the 0.005 – 0.1 mm (0.0002 – 0.004 in) range | Tolerances range in the micron (thousandth of a millimeter) range |
| Repeatability | Good repeatability | Exceptional repeatability with minimal variations |
| Machine Types | Mills, lathes, routers, etc. | High – precision CNC machines |
| Applications | Suitable for a wider range of parts, from prototypes to production components | Medical devices, aerospace components, and other complicated molds |
| Cost | Generally less expensive | More expensive |
3.Advantages of CNC precision machining
CNC precision machining has significant advantages. Currently, the most modern manufacturing methods allow you to manufacture custom metal parts with the most complex designs. Interestingly, with precision CNC machining, we can achieve high precision. This is what makes it superior to other manufacturing methods.
The most important advantage of CNC precision machining is the high precision of manufactured parts, which is almost impossible to achieve in the case of manual machining. These capabilities bring multiple advantages to different industries. Let’s take a deeper look:
1) Higher accuracy and repeatability
CNC precision machining is particularly good at measuring tolerances in the micron range. These tolerances ensure that all end products meet the expected results. For example, their performance in industries such as medical devices and aerospace components should be optimal.
Since CNC precision machining is an automated technology, it can eliminate even small human errors in the machining process. Each part is manufactured as designed, ensuring perfect repeatability.
2) Design freedom
CNC precision machining can handle complex designs and geometries efficiently. On the other hand, traditional machining has difficulty in manufacturing parts with complex designs. By combining advanced tool paths and 4-axis machining/5-axis machining capabilities, CNC precision machining centers can manufacture high-precision parts of any complexity.
Ultimately, these features give CNC part designers great freedom to design anything that will perfectly match the machine for better performance. As a result, they can manufacture more precise parts required by the medical and automotive industries.
3) Wider Selection of Materials
One of the best features of CNC precision machining is its ability to machine a wide range of materials. Its capabilities are not limited to metals, but it can also machine plastics and other special materials such as Titanium and Inconel. Therefore, this feature allows manufacturers and designers to choose the best material to meet their project requirements.
Since mass production is costly, better material selection becomes even more important, so professional high-precision CNC machining services can guide you effectively.
4) Superior Productivity and Efficiency
CNC machining has excellent productivity. Not only that, it can also speed up the prototyping process to manufacture customized parts in large quantities. Carrying out the entire process on a high-precision machine increases the efficiency of these parts. Therefore, we can effectively control costs and produce efficient parts quickly without losing quality.
5) Enhanced Safety
Modern CNC machines are fully automated, which greatly reduces human interference. Likewise, the manpower required to perform different operations is minimal. Therefore, there is little chance of accidental injury. In addition, precision machining companies place these machines in enclosed spaces with little dust and smoke. Ultimately, this leads to a better and safer working environment.
4.What are the tolerances of precision machining?
Strict tolerances and repeatability determine the level of accuracy and consistency in the manufacturing process of CNC precision machining parts. If we look into the definition of precision machining tolerances, it represents the acceptable range within which the actual machining dimensions can vary.
In general, these errors are expressed in units such as millimeters (mm) or inches (in). The smaller the error, the higher the accuracy.
1) What is the significance of tolerances in precision machining?
Tolerances directly affect the performance of the final product. Strict tolerances ensure that all assembled parts fit smoothly without any problems. For example, a bearing with too large a tolerance will cause failure during operation. This will lead to premature wear.
Therefore, the strict tolerances of CNC precision machining parts make assembly extremely convenient. At the same time, good tolerances will lead to cost-effective machining.
2) Different Types of Tolerances
There are generally two types of tolerances
- Dimensional Tolerances
Dimensional tolerances refer to the level of acceptance of variations in dimensional features such as length, width, height, and bore diameter.
- Geometric Tolerances
In contrast to geometric tolerances, geometric tolerances are defined as the permissible deviations in the form and position of custom metal parts.
5 Factors Affecting Precision CNC Machining Tolerances
- Machining Capabilities
- Tool Wear
- Material Properties
- Fixtures
- Workholding
5.Types of CNC Precision Machines
There are different types of precision CNC machine tools that can be used to manufacture precision parts. Understanding the characteristics of each type is essential for project success.
1) CNC Milling Machines
CNC milling machines are effective in manufacturing high-quality parts with rich details and a smooth finish. CNC milling machines use rotating tools (cutters) to machine materials and provide instructions for machining materials based on CAD files.
2) CNC Lathes
Modern CNC lathes use flat cutters, etc., so the space allocated to the machining area can be increased. Therefore, CNC lathes are now the first choice when it comes to high-precision CNC machining. CNC lathes are capable of manufacturing precision metal parts.
3) Swiss Lathes
Swiss-type lathes offer a cost-effective way to produce small, complex, and high-precision CNC machined parts. One thing to remember is that manual programming on the controller is inefficient. Thanks to the intuitive channel synchronization manager, programming setup, milling, and turning operations on the main and back spindles and synchronizing them becomes simple and effective.
6.Application of Precision CNC Machining
After incorporating modern high-precision CNC machining technology, the application range of machined parts has been greatly expanded. Here we introduce some of the main industries where precision machined parts are applied.
1) Aerospace Industry
The aerospace industry is one of the biggest beneficiaries of high-precision machined parts. For many years, the aerospace industry has been receiving complex engine parts from machining companies. Some of the prominent parts used in these industries include landing gear, fuselage sections, turbine blades, and combustion chambers.
2) Automotive Industry
The automotive industry often uses precision parts to manufacture metal cylinder blocks, gears, pins, valves, shafts and other parts, as well as dashboard and indicator components made of plastic.
Precision CNC machines are also used to produce prototype automotive parts and spare parts. The reason for this is shorter delivery times and more freedom in part manufacturing.
3) Electronics
CNC machining is very popular in prototyping and manufacturing systems as well as consumer electronics. In electronics, CNC precision machines are used to manufacture printed circuit boards and solder components.
4) Defense
The military industry is another major industry that uses high-precision parts in weapon systems. Prototype CNC machining plays a key role in manufacturing durable, reliable and long-lasting parts. The ability of precision CNC machines to produce prototype parts and efficient components on demand is particularly useful.
5) Pharmaceuticals
Precision metal parts are used in diagnostic machines and metal tools in almost every healthcare sector due to the high practicality and safety of precision CNC machines in processing medical component materials. For example, surgical instruments, orthopedics, implants and medical devices.
7.CNC Precision Machining Materials
A successful CNC machining project depends largely on process and material selection. Therefore, choosing the right material for precision machined parts is essential to achieve the desired results. This can not only save a lot of costs but also improve product performance.
Below, we have given a comprehensive table of recommended materials:
| Material Category | Examples | Properties | Considerations for Selection | Impact on Achievable Tolerances |
| Metals | AluminumSteelTitanium | High StrengthCorrosion resistance (varies) | Strength requirementsWeight limitationsHeat and corrosion resistanceHigh costs | Harder materials |
| Plastics | ABSPolycarbonate (PC)EngineeringThermoplastics (PEEK, PEI) | Lightweight (ABS)Transparency (PC)Heat resistance (engineering thermoplastics) | Strength requirements Weight limitationsImpact resistance (PC)Chemical resistance | Generally softer and easier to machine than metals |