Ingress Protection and 3D Printing: How to Design IP Rated Parts

When designing enclosures for electronic devices or other products, it is important to consider the environment in which the product will be used. In many cases, the product may be exposed to dust, water, or other elements that could potentially damage the internal components. To ensure that the product can withstand these conditions and continue to function properly, it is important to design the enclosure with IP ratings in mind.

IP ratings, or Ingress Protection ratings, quantify how resilient a product is to intrusions such as dust and water. By designing an enclosure to meet a specific IP rating, you can ensure that the product will be able to withstand exposure to these elements and continue to function properly in aerospace, automotive, and medical device applications.

In this comprehensive guide, we will discuss what IP ratings are and how they work, provide best practices for designing enclosures to meet specific IP ratings, and explore how 3D printing technologies can be leveraged to create waterproof and dust-proof components. By following these guidelines, you can design enclosures that are able to withstand exposure to dust and water and ensure that your product continues to function properly in a variety of challenging environments.

Understanding IP Ratings

IP ratings, or Ingress Protection ratings, are a standardized system for quantifying how resilient a product is to intrusions such as dust and water. The rating consists of the letters IP followed by two digits. The first digit indicates the level of protection against solid foreign objects, while the second digit defines the protection against various forms of moisture.

Complete IP rating system showing first digit (solids protection) and second digit (liquids protection)

First Digit: Solid Object Protection

The first digit in an IP rating indicates the level of protection against solid foreign objects, ranging from 0 (no protection) to 6 (complete protection against dust ingress):

Second Digit: Liquid Ingress Protection

The second digit indicates protection against liquid ingress, ranging from 0 (no protection) to 8 (protection against continuous submersion):

Common IP Rating Examples

For example, an IP rating of IP65 means that the product is completely protected against dust (the first digit is 6) and is protected against water projected from a nozzle (the second digit is 5). This makes IP65 ideal for outdoor electronic enclosures, automotive components, and clean technology applications.

IP ratings are defined by the international standard IEC 60529. This standard provides detailed explanations of each level of protection and specifies the tests that must be performed to verify that a product meets a specific IP rating. It is important to note that IP ratings only provide information about a product's protection against dust and water, not other factors such as impact resistance or chemical resistance.

Best Practices for Designing Enclosures for IP Ratings

When designing enclosures to meet specific IP ratings, several best practices ensure your product can withstand exposure to dust and water in aerospace, automotive, and medical device manufacturing applications.

Material Selection

The materials used to construct the enclosure can have a significant impact on its ability to withstand exposure to dust and water. Be sure to choose materials that are appropriate for the desired IP rating, considering chemical resistance, UV stability, and dimensional stability.

Sealing Strategies

To prevent dust and water from entering the enclosure, it is important to ensure that all seams and openings are properly sealed. This can be achieved through the use of gaskets, sealants, or other sealing methods.

Testing and Validation

Professional IP rating validation requires controlled testing environments and specialized equipment. Understanding test procedures helps ensure your design meets certification requirements.

Professional IP testing equipment ensures accurate certification and validation

Designing 3D Printed Parts for IP Ratings

Most people don't think of 3D printed parts when designing to meet IP ratings, but there are a variety of 3D printed materials and processes that can be used to produce watertight parts.

Fused Deposition Modeling (FDM) Applications

Due to the nature of the technology, Fused Deposition Modeling (FDM) parts are not usually watertight right off the printer, since there are small gaps between the extruded layers of material. However, it is possible to increase the number of perimeters (between 4 and 6) to improve watertightness. Using a higher print temperature can also help by increasing layer adhesion, closing gaps.

In terms of post processing, FDM parts can be vapor smoothed, which is a process that involves bathing the parts in a solvent vapor, causing the material to soften and flow together, closing all gaps and producing a smooth glossy surface finish.

FDM part before and after vapor smoothing - the finished part achieves watertight performance

Stereolithography (SLA) for Watertight Applications

Parts made with Stereolithography (SLA) technology are isotropic and therefore watertight, which makes them excellent for not only IP rated enclosures, but even containers for holding liquids or fluid flow applications.

Selective Laser Sintering (SLS) Considerations

Selective Laser Sintering (SLS) parts are made with a fused powder process, and they are considered isotropic in the context of part strength, but they have inherent porosity. They are water resistant but won't remain watertight over time.

Gasket sealing between two mating surfaces ensures proper environmental protection

PolyJet Multi-Material Prototyping

If you want to prototype an IP rated design that includes gaskets or overmolds, then we recommend PolyJet. It is not suitable for end use parts, but PolyJet parts can be printed in multiple durometers, which means you can simulate overmolds, gaskets and watertight buttons easily.

Universal Post-Processing Solutions

All of the above 3D printed parts can be treated with an epoxy coating to make them watertight as well. This provides additional protection for demanding applications across industries.

Conclusion

Designing enclosures with IP ratings in mind is an important consideration for many products. By understanding how IP ratings work and following best practices for designing enclosures to meet specific IP ratings, you can ensure that your product is able to withstand exposure to dust and water and continue to function properly.

Whether you're developing prototypes for rapid iteration or preparing for volume production, understanding IP requirements and leveraging the capabilities of additive manufacturing can lead to more innovative, cost-effective, and reliable environmental protection solutions.