Cryogenic Deburring Delrin


delrin cnc machining and deburring

Introduction to Delrin

Delrin is a brand name for a type of acetal resin, specifically polyoxymethylene. It is a high-performance thermoplastic that is known for its excellent mechanical properties, dimensional stability, and low friction characteristics. It is widely used in various industries for its versatility and durability.

CNC Machining Delrin

Delrin (polyoxymethylene) is a thermoplastic material that can be CNC machined using standard machining techniques. Here is a general overview of the CNC machining process for this material:

  • Design: Create a detailed design of the desired Delrin component using computer-aided design (CAD) software. This design will serve as a blueprint for the CNC machine.
  • Material selection: Choose the appropriate grade and size of Delrin stock material. Delrin is available in sheets, rods, and blocks, so select the form that best suits your project requirements.
  • CNC programming: Generate a CNC program based on the CAD design. This program will provide instructions for the CNC machine to accurately cut and shape the material.
  • Machine setup: Set up the CNC machine by securing the stock material onto the machine’s worktable or chuck. Ensure that it is properly aligned and clamped to prevent movement during machining.
  • Tool selection: Select the appropriate cutting tools for machining. Carbide or high-speed steel (HSS) tools with sharp edges are commonly used for Delrin machining due to their ability to produce clean cuts and withstand the material’s low melting point.
  • Machining process: The CNC machine will follow the programmed instructions to cut and shape the material. The specific machining operations will depend on the desired component, such as milling, turning, drilling, or threading.
  • Coolant and lubrication: It has a relatively low melting point, so using coolants or lubricants during machining is essential to dissipate heat and prevent melting or material deformation. Water-based coolants or air can be used to keep the tool and workpiece cool.
  • Quality control: Regularly inspect the machined Delrin component to ensure it meets the desired specifications. Use measurement tools such as calipers or micrometers to verify dimensions and tolerances.

Delrin is known for its excellent machinability, but there are a few factors to consider during the machining process:

  • Delrin has a relatively low melting point, so it is important to use appropriate cutting speeds and feeds to avoid excessive heat buildup.
  • Use sharp cutting tools to minimize heat generation and achieve clean cuts. Dull tools may cause material smearing or poor surface finish.
  • Delrin can produce stringy chips during machining. Proper chip evacuation methods, such as using compressed air or chip brushes, should be employed to prevent chip buildup and ensure smooth machining operations.

Following proper machining techniques and guidelines for the material will help achieve accurate and high-quality results. It is also recommended to consult with experienced machinists or CNC service providers who have expertise in machining Delrin for best practices and advice specific to your project.

Delrin Burrs

When machining Delrin (polyoxymethylene) using conventional methods, the formation of burrs is generally minimal compared to some other materials. This material has good chip formation characteristics, which can help reduce burr formation. However, it is still possible to encounter some burrs during the machining process.

Here are a few factors that can influence the formation of burrs when machining Delrin:

  • Cutting tool selection: Choosing the appropriate cutting tool geometry and sharpness is important to minimize burr formation. Using tools with a high rake angle and sharp edges can help produce cleaner cuts and reduce burring.
  • Cutting speed and feed rate: Optimal cutting parameters, including the cutting speed and feed rate, need to be determined for machining. Using the right speeds and feeds can help control chip formation and reduce the likelihood of burr formation.
  • Tool wear: Dull or worn-out cutting tools can contribute to increased burring. Regularly inspecting and replacing tools when necessary is important to maintain machining quality and minimize burr formation.
  • Machining technique: The machining technique employed can also affect burr formation. Techniques like climb milling, where the tool cuts against the direction of workpiece movement, tend to produce fewer burrs compared to conventional milling.

While Delrin typically produces fewer burrs compared to many other materials, it is still important to inspect machined parts for burrs and perform any necessary deburring operations to achieve the desired surface finish and functionality.

Deburring can be accomplished using various methods such as manual deburring with files or deburring tools, tumbling, abrasive blasting, or chemical deburring processes. The specific deburring method will depend on the size, complexity, and tolerance requirements of the machined Delrin component.

Overall, Delrin’s good chip formation characteristics and machinability contribute to reduced burr formation. However, it is essential to consider the machining parameters, tool selection, and deburring processes to achieve the desired surface finish and dimensional accuracy while minimizing burrs.

Cryogenically Deburring

Delrin, polyoxymethylene, can be cryogenically deburred. Cryogenic deburring is a process that involves exposing the machined components to extremely low temperatures to remove burrs and improve surface finish.

In the cryogenic deburring process, the Delrin components are immersed in a cryogenic fluid, such as liquid nitrogen in its gaseous form, which has a very low temperature. The parts are then tumbled or blasted with a media, such as plastic beads, to break off the brittle flash. The cryogenic media helps to efficiently remove the burrs while minimizing damage to the part itself.

Cryogenic deburring offers several advantages, including:

  • Burr removal: Cryogenic deburring can effectively remove burrs from the components, including small or complex geometries that are challenging to deburr using traditional methods.
  • Preservation of material properties: Cryogenic deburring is a non-destructive process that does not affect the mechanical or dimensional properties of the material. It helps preserve the material’s original characteristics.
  • Improved surface finish: Cryogenic deburring can also improve the surface finish of the machined components, providing a smoother and more aesthetically pleasing appearance.

It’s important to note that while Delrin can be cryogenically deburred, the effectiveness of the process may depend on the specific design, size, and complexity of the component, as well as the severity of the burrs. Therefore, it’s recommended to consult with a cryogenic deburring service provider or conduct testing to determine the suitability and effectiveness of cryogenic deburring for your specific Delrin components.

Want to send in your Delrin parts for a no-cost deburring evaluation? Learn more by contacting us at 508.459.7447×105 or email us at