Polyoxymethylene (POM), commonly known as Delrin or Acetal, is a high-performance engineering plastic that is gaining traction in CNC machining applications as a result of the need for high-performance engineering plastics for precision manufacturing.Known for its excellent dimensional stability, low friction, and high strength, POM is a versatile material that meets the rigorous standards of industries ranging from automotive to electronics.This comprehensive guide explores what POM is, the advantages of CNC machining POM, and more.


What is POM?
POM, or polyoxymethylene, is a high-performance thermoplastic that is commonly known as Delrin. While POM is the general term used to describe this type of polymer, Delrin is actually a brand name owned by DuPont. The terms POM and Delrin are often used interchangeably, but it’s important to note that Delrin refers specifically to the high-quality grade of POM produced by DuPont.
It is prized for its exceptional mechanical properties, which include high strength, stiffness, and excellent dimensional stability. This material is characterized by its low friction coefficient and resistance to wear, making it ideal for precision engineering applications.
Properties of Delrin
Superior Impact and Creep Resistance
Delrin offers excellent impact resistance, which allows it to endure sudden shocks without cracking or breaking. Its resistance to creep ensures long-term stability even under continuous load.
High Strength and Stiffness
With high tensile strength and rigidity, Delrin can withstand heavy mechanical stress without losing its shape, making it ideal for structural components and moving parts.
Low Friction
The low friction coefficient of Delrin reduces wear and tear, making it perfect for applications like gears, bearings, and bushings that require smooth, continuous motion.
Excellent Machinability
Delrin is known for its ease of machining, allowing it to be easily cut, drilled, and shaped with high precision, even into intricate designs.
Dimensional Stability
Delrin maintains its dimensions under varying environmental conditions, ensuring parts retain their precise fit and functionality, even with temperature fluctuations.
Low Moisture Absorption
The low moisture absorption of Delrin ensures that it maintains its mechanical properties and dimensional integrity, even in humid environments, minimizing expansion or warping.
What is POM CNC machining?
CNC machining Delrin refers to the process of using computer-controlled machines to cut, shape, and mill POM (Delrin) into precise parts and components. The high machinability of Delrin makes it an excellent choice for CNC machined POM parts, allowing for intricate designs and tight tolerances. CNC machining enables the creation of complex geometries with smooth finishes, ideal for applications that require durability, wear resistance, and dimensional stability.
Due to its low friction, high strength, and ease of machining, CNC machining Delrin is commonly used in industries like automotive, aerospace, and consumer products. The precision achieved in CNC machined POM parts ensures consistent performance, even in demanding environments.


Benefits of Machining Delrin Material
Exceptional Machinability
Delrin is known for its exceptional machinability, making it easier to cut, shape, and finish with precision. The material’s low tool wear rate ensures that machining processes can be completed efficiently, even for complex and intricate designs. This advantage reduces overall production costs and time, especially when manufacturing high-volume parts.
Chemical and Moisture Resistance
Another significant benefit of machining Delrin is its chemical resistance. It is highly resistant to a wide range of chemicals, oils, and solvents, which makes it a preferred material for applications in harsh environments. Additionally, Delrin has low moisture absorption, ensuring that it maintains its dimensional stability and mechanical properties even in humid or wet conditions.
High Strength and Durability
One of the key benefits of machining Delrin is its remarkable strength and durability. It has a high tensile strength, which allows it to withstand heavy loads and mechanical stress without warping or breaking. This makes Delrin a reliable material for producing high-performance components in demanding applications, such as automotive and industrial machinery.
Low Friction and Wear Resistance
With its naturally low friction coefficient, Delrin is an ideal material for creating components that require smooth, consistent motion, such as gears, bearings, and bushings. The material’s wear resistance further enhances its suitability for parts that are exposed to constant mechanical movement, ensuring longer lifespans and reduced maintenance needs.
Machining methods for Delrin Parts
CNC Milling
CNC milling is a highly effective method for machining Delrin parts. This Delrin machining process uses rotating cutting tools to remove material from the workpiece. It is ideal for creating complex geometries, including holes, slots, and contours. The precision and speed of CNC milling make it perfect for high-tolerance Delrin components, ensuring smooth finishes and tight dimensions.
CNC Turning
CNC turning is another common method for machining Delrin parts. In this process, the material is rotated against a stationary cutting tool to shape the part. This technique is particularly effective for producing cylindrical or round parts, such as shafts, bushings, and rings. CNC turning offers excellent accuracy and surface finish, making it a preferred choice for Delrin parts requiring precise dimensions and smooth edges.
Finishes of Machined Delrin Parts
- Machined Surface
The machined surface of Delrin parts is typically smooth, with a clean finish achieved directly through CNC milling or CNC turning. While not polished, this finish often provides adequate smoothness for many applications. The surface can exhibit slight tool marks, but these are generally minimal and do not affect the part’s functionality, making it suitable for a variety of industrial uses.
- Sandblasting Finish
Sandblasting is a surface treatment used to enhance the appearance and texture of Delrin parts. In this process, abrasive materials are propelled at high speed onto the part’s surface, creating a matte or slightly textured finish. This method improves grip and reduces the visibility of machining marks, making it ideal for parts that require an aesthetically pleasing, uniform, non-reflective surface.
Cost-Efficient Design Strategies for CNC Machining Delrin
To optimize the cost efficiency of CNC machining Delrin, careful design choices can significantly reduce production expenses.
- Designing parts with simplified geometries can minimize machining time and reduce tool wear. Avoiding overly complex shapes helps reduce manufacturing costs and the potential for errors during production.
- Minimizing the number of operations required for machining can also save costs. For example, reducing the need for multiple setups or tool changes can ensure a smoother workflow and less time on the machine.
- Ensure that the part is oriented in a way that allows for efficient cutting paths, minimizing unnecessary movements or setups. By utilizing the right tolerances—neither too tight nor too loose—you can avoid costly reworks or errors during production.
- Considering material utilization is also essential. Efficient part layout on the sheet of material can reduce scrap, ensuring that more parts can be produced from each piece of Delrin, thereby reducing material costs.
Applications for POM in CNC Machining


- High-Rigidity and Strength Bushings and Fixtures
POM is an excellent choice for manufacturing bushings and fixtures due to its high rigidity and strength. These components require materials that can withstand high loads and provide stable support in precision machining applications. POM’s toughness and dimensional stability make it ideal for these uses, ensuring long-lasting performance even under stress.
- Medical Devices and Instruments
In the medical field, POM is used to create components that require both strength and biocompatibility. POM is resistant to moisture and chemicals, making it an excellent material for medical devices and instruments that are exposed to harsh conditions. It is commonly used in syringes, surgical tools, and diagnostic equipment, offering precise machining and durability.
- Electrical Housings and Insulation
POM’s electrical insulating properties make it suitable for electrical housings and components requiring insulation. It is used to manufacture parts like connectors, enclosures, and terminals, which need to resist electrical conductivity while maintaining structural integrity.
- Automotive Applications and Construction
The automotive industry benefits from POM in the production of lightweight, high-strength components. It is used in various automotive applications such as gear parts, bushings, and structural components, where durability, low friction, and wear resistance are essential.
- Seals, Handles, Valves, and Gear Manufacturing
POM is commonly used for producing seals, handles, valves, and gears due to its excellent wear resistance and low friction properties. The material’s ability to withstand constant movement and pressure makes it ideal for manufacturing high-performance parts, such as those found in industrial equipment, pumps, and machinery.
Conclusion
POM (Delrin/Acetal) is a highly versatile and reliable material for CNC machining, offering exceptional strength, durability, and precision. Its wide range of applications, from automotive parts to medical devices, demonstrates its importance in industries requiring high-performance components.For businesses or individuals in need of POM machining, Whether you’re producing small custom parts or large-scale production runs, EASIAHOME is equipped to deliver precise and cost-effective solutions tailored to your needs.
Frequently Asked Questions
Q: Are POM and Delrin the same?
A: POM (Polyoxymethylene) and Delrin are closely related but not the same. Delrin is a specific brand name for a high-performance POM polymer produced by DuPont.While POM refers to the generic material, Delrin is a type of POM with enhanced properties, including superior mechanical strength, dimensional stability, and resistance to wear and chemicals.
Q: What is the difference between acetal and Delrin machining?
A: Acetal is the general name for a family of thermoplastics, including both POM and Delrin. In terms of CNC machining, both acetal and Delrin can be machined with similar techniques, but Delrin often provides a smoother finish and better dimensional stability during the process.
Q: Is Delrin stronger than Nylon?
A: Yes, Delrin is generally stronger than Nylon in terms of mechanical properties. Delrin offers superior tensile strength, stiffness, and resistance to wear and creep, making it ideal for applications requiring high load-bearing capabilities. Nylon, on the other hand, has excellent impact resistance and flexibility but typically has lower strength and stiffness than Delrin.