How to Waterproof 3D Printed Parts

Understanding the Challenges of Waterproofing 3D Printed Parts

As 3D printing technology continues to evolve, more and more industries are adopting it for their manufacturing needs. However, one of the major challenges with 3D printed parts is waterproofing them. Unlike traditional manufacturing methods, 3D printing creates parts layer by layer, which can result in small gaps and spaces that allow water to seep through. Additionally, the materials used in 3D printing can be porous, which further complicates the waterproofing process.

The Importance of Waterproofing 3D Printed Parts

Waterproofing is crucial for many applications of 3D printed parts. For example, in the automotive industry, 3D printed parts may need to be waterproof to prevent damage from exposure to rain or moisture. Similarly, in the medical industry, 3D printed prosthetics or implants may need to be waterproof to prevent infection or damage to the surrounding tissue.

Choosing the Right Material for Waterproof 3D Printing

Choosing the right material is the first step in waterproofing 3D printed parts. While some materials, such as ABS, are naturally waterproof, others may require additional treatment to become waterproof. One popular method of waterproofing 3D printed parts is using a sealant or coating.

A crucial aspect of 3D printing is waterproofing the parts, which can be challenging due to their porous and layered nature. Choosing the right coating material, such as epoxy resin, polyurethane, or acrylic, is important, along with applying multiple coats and allowing sufficient drying time. Sanding and finishing the part can also help create a consistent surface for the coating to adhere to. Testing the waterproofing is essential to ensure that the part is fully waterproof and suitable for its intended application.

Popular Coating Materials

  • Epoxy Resin: Epoxy resin is a popular coating material for 3D printed parts. It creates a hard, waterproof shell that is resistant to moisture and chemicals. However, it can be challenging to apply and may require multiple coats to achieve the desired level of waterproofing.
  • Polyurethane: Polyurethane is another popular coating material for 3D printed parts. It is easy to apply and creates a flexible, waterproof barrier. However, it may not be as durable as epoxy resin and may require more frequent reapplication.
  • Acrylic: Acrylic is a fast-drying, waterproof coating material that is often used to seal 3D printed parts. It is easy to apply and can be tinted to match the color of the part.

Tips for Waterproofing 3D Printed Parts

Once you have chosen the right material, there are several tips and tricks that can help you achieve the best results when waterproofing 3D printed parts.

Sanding and Finishing

Before applying any coating or sealant, it is essential to sand and finish the 3D printed part. Sanding the part can help to smooth out any rough edges or imperfections, while finishing can help to create a more consistent surface for the coating to adhere to.

Multiple Coats

When applying a coating or sealant to a 3D printed part, it is often necessary to apply multiple coats. This is because the porous nature of the material can make it difficult for the coating to penetrate all the way through. Applying multiple coats can help to ensure that the part is fully waterproof.

Drying Time

The drying time for the coating or sealant is also crucial. It is essential to follow the manufacturer’s instructions and allow enough time for the coating to dry fully before using the part. Rushing the drying process can result in a coating that is not fully waterproof and may be prone to peeling or flaking.


Testing the waterproofing of the 3D printed part is also important. This can be done by applying water to the part and observing if it seeps through or not. If it does, additional coats or a different coating material may be necessary.

FAQs for How to Waterproof 3D Printed Parts

What materials can be used to waterproof 3D printed parts?

There are several materials that can be used to waterproof 3D printed parts, including epoxy coatings, polyurethane coatings, silicone coatings, and various types of sealant sprays. Each material has its own unique properties and levels of effectiveness, so it’s important to research and choose the right one based on your specific needs and the requirements of your project.

How do I apply a waterproof coating to my 3D printed part?

The exact process for applying a waterproof coating will depend on the specific material being used. In general, the first step is to clean and dry your 3D printed part thoroughly. Then, apply the waterproof coating according to the manufacturer’s instructions, making sure to cover the entire surface of the part. Allow the coating to dry completely before using or installing the part.

Can I make my 3D printed part completely waterproof?

While it is possible to make a 3D printed part highly water-resistant, achieving complete waterproofing can be difficult. The level of waterproofing you can achieve will depend on the materials and techniques you use, as well as the design and construction of the part itself. Keep in mind that certain types of 3D printing materials, such as ABS and nylon, are naturally more water-resistant than others.

What are some tips for waterproofing small or intricate 3D printed parts?

For small or intricate 3D printed parts, it may be helpful to use a sealant spray rather than a coating. This can help ensure that all surfaces of the part are fully covered, even in hard-to-reach areas. You can also use a small brush or applicator tool to carefully apply the waterproofing material to small or delicate parts.

How do I test the effectiveness of my waterproofing?

To test the effectiveness of your waterproofing, you can conduct a simple water immersion test. Simply submerge your 3D printed part in water for a set amount of time and then inspect it for signs of water penetration. If water has penetrated the surface or is trapped inside the part, you may need to apply additional waterproofing or adjust your technique.