Delrin CNC Machining: The Comprehensive Guide

Delrin also known as Acetal plastic is a very commonly used material and you can find it in various products ranging from automobiles to electronic appliances as it has various applications to cater to. It is a very strong form of thermoplastic and offers excellent performance and high machining capability. However, to work with Delrin you must know the details of Delrin CNC machining which you will find in the guide below, so let's explore.

What is Delrin?

Delrin is a semi-crystalline thermoplastic which is known for its low friction coefficient and high tensile strength. It also offers high wear resistance and is used widely for manufacturing components through CNC machining.

The main reason for using Delrin for CNC machining is because of its durability, mechanical strength, and structural integrity. It is available in various colors and has a high melting point. Delrin is available in the form of bars and sheets and can easily be subjected to CNC machining.

Delrin works very well with high-end tools for cutting and it offers suitability for high-load mechanical applications.

Advantages of Delrin CNC Machining

Delrin machining is equipped with multiple advantages some of which are as follows:

High Machinability: Delrin offers seamless machinability and is suitable for manufacturing components that have tight tolerance and complex geometries. It offers a very good dimensional stability and creep resistance which makes it easy to cut with precision. It doesn't even need special tools and can be cut using the basic ones.

Enhanced Dimensional Stability: Delrin has a very good dimensional stability and despite being subjected to stress it can retain its stability. The machining process is equipped with pressure, stress, and very high temperature but due to its dimensional stability, it gets very easy to machine it.

Light In Weight: When compared to metals the weight of Delrin is very light whereas the strength-to-weight ratio is quite high. Hence, it can be used to create Delrin machined components that can withstand a lot of stress despite being lightweight.

Excellent Rigidity: Delrin is known for its high impact strength which ranges between 7000 to 9000 PSI. The components made using Delrin do not break and are quite tough. It consists of high stiffness, offers excellent mechanical strength, and therefore is suitable for high performance.

Low Moisture Absorption: Delrin possesses a low rate of moisture absorption when subjected to the dampest conditions when compared to other types of thermoplastics. Due to this property of Delrin, it proves to be quite suitable for wet environments. Also, due to its moisture resistance, the material is capable of maintaining its structural integrity in underwater applications as well.

Versatile Applications: CNC-machined Delrin parts are used in multiple industries. This material is known for its properties like lightweight, high mechanical strength, and low moisture absorption which means it can cater to versatile applications. Delrin also offers resistance against high temperatures and hence can be used in applications that are subjected to extreme temperatures.

Limitations of CNC Machining Delrin

CNC machining Delrin offers various benefits but at the same time has certain limitations too, some of these limitations are as follows:

Thermal Sensitivity: When compared to other materials, Delrin has a low thermal deformation rate, but still, in some cases where the temperature is too high, it can deform which means applications that need high heat resistance may not find Delrin components suitable enough.

Machining Constraints: Delrin is known for its high machining capability but sometimes it may lead to chip build-up which causes machining constraints. Hence it is very important to have appropriate machining tools and parameters for avoiding these issues.

Chemical Resistance: Delrin is not resistant to acids and bases and when subjected to environments that are equipped with harsh chemicals, Delrin may degrade quicker than other types of materials.

Impact Resistance: Despite having good impact resistance compared to other types of plastics, Delrin can sometimes crack under high stress being a little brittle.

High Cost: Delrin is extensive and when you compare it with other types of plastic it may lead to making your project expensive and out of budget.

Surface Finishes for CNC Machined Delrin Parts

The CNC-machined Delrin parts may require some additional surface finishing processes to enhance the performance and usability of the components. Some of the possible surface finishing processes for Delrin parts are given below.

As-Machined

The as-machined surface finishing is the finish of the surface achieved right after CNC machining. Many applications find the surface after CNC machining suitable however it may have a rough texture and some tool marks are visible. As-machined surface finishing is mostly opted for functional parts where there is no significance of appearance like some internal components.

Polishing

Polishing adds a smooth surface layer to the Delrin components. The process consists of rubbing the component with sandpaper first so that smoothness can be attained and after that, a high gloss polish is applied for a neat and shiny finish offering a clean appearance and smooth touch. The process of polishing is suitable for visible components in consumer products, cosmetic enclosures, etc

Bead Blasting

The process of bead blasting involves blasting the surface of the Delrin component with small beads using pressure and it creates a matte and uniform texture. It is a suitable process in applications where a non-reflective surface finish is required. The process of bead blasting is opted for mechanical components which are later either coated or painted.

Protective Coating

Applying a protective coating can enhance the properties of the Delrin components and make them more scratch-resistant. However, the selected coating must be compatible with Delrin material. The protective coating is most commonly applied in decorative elements and such components that are exposed to harsh environments.

Applications of Delrin CNC Machining

There are multiple applications of Delrin CNC machining, acetal machining is used in many industries and some of these applications are as follows:

Automotive

Delrin parts are known to be very strong and offer low friction, therefore they can be suitable for automotive parts. In vehicles gears and bushing need durability and movement with precision which can be achieved by acetal plastic machining. Also, the wear resistance of these parts makes them suitable to work in high-stress systems of automobiles.

Aerospace

In the aerospace industry, Delrin is suitable because of its high strength-to-weight ratio and that it offers resistance against deformation which is very important for parts like actuators and bearing housings. These parts are highly precise and the stability offered by them ensures performance and reliability in the aerospace environments.

Machine Components

The low friction and durability present in Delrin parts make them suitable for manufacturing components used in industrial machinery. Components like guide rails, and conveyor systems need to be capable of withstanding consistent use and repetitive motion. Hence to ensure reliable and smooth operation in industrial settings these components are manufactured through CNC machining Delrin.

Medical

Delrin is used in medical devices because it offers properties like precision, cleanliness, biocompatibility, and resistance against wear and tear. Components in surgical instruments, and diagnostic components are manufactured using machining acetal. It offers tight tolerance and wear and tear resistance as required by medical devices.

Consumer Electronics

Delrin offers an aesthetic appearance in components and also has very good machinability, therefore it is used for internal components and housings for consumer electronics. These components need durability as well as a fine appearance to enhance the design and functionality of the electric device.

Tips for CNC Machining Delrin

Delrin is a very machine-friendly plastic and therefore it doesn't need very crucial precautionary measures but still, some important tips for CNC machining Delrin may help with a better outcome.

1. The wall thickness for the Delrin machined components must be consistent and where required the ribs and filets should be included, the larger parts have more chances of warping.
2. The use of air-based coolants during the machining process of Delrin is very important as it is sensitive to temperatures that go above 121 degrees centigrade.
3. The tools used in the CNC machining of Delrin should be kept clean at all times so that the buildup on the tool can be avoided.
4. CNC machining Delrin requires sharp cutting tools to achieve the best results also the cutting lubricant must be implemented for an optimal and neat finish.
5. During the CNC machining process of Delrin, the work holding shouldn't be too tight, and rather light clamps must be used for holding the workpiece.

Conclusion

Delrin plastic or acetal plastic has a very crucial role to play in various industries the products of which are used on a regular basis in every application. Hence, learning about the CNC machining process associated with this material plays a vital role in ensuring that you can make the right selection of this material for your components. As you have gone through the guide above you must have learned everything starting from the benefits, limitations, and applications of Delrin.

CNC Machining Delrin at DEK

When it comes to choosing a manufacturer for custom CNC machined Delrin parts you can always count on DEK. We offer a wide range of components made using Delrin through CNC machining which is accurate, durable, and precise. You can always provide us with your specifications and we can produce samples for you at affordable prices that suit your application requirements. So, get in touch with our sales team today and get a free quote.

FAQs

Is Delrin stronger than nylon?

Delrin has a high strength and stiffness, it also offers impact resistance and dimensional stability which is superior to nylon.

Can you laser-cut Delrin?

Yes, Delrin can be subjected to laser cut and the best type of laser for Delrin is CO2 laser which offers precise edge and minor thermal distortion.

How do you cut Delrin plastic?

Delrin can be cut using processes like CNC milling and CNC turning and for these two processes, it is usually present in the form of sheets or extruded bars. It can also be cut with the help of a laser cutter and if in the form of granules, it is subjected to plastic extrusion and injection molding.