Skip to Content

Is PETG Good for Mechanical Parts? 5 Things To Know

PETG is becoming increasingly popular in 3D printing, especially since one of its components (glycol) has been linked with reducing overheating, fragility, and cloudiness. However, there are several vital things that you need to know when it comes to its application in creating mechanical parts. 

Written by:
Ben
Last updated:
11/16/2023

PETG is becoming increasingly popular in 3D printing, especially since one of its components (glycol) has been linked with reducing overheating, fragility, and cloudiness. However, there are several vital things that you need to know when it comes to its application in creating mechanical parts. 

PETG is good for 3D-printing mechanical parts due to its heat, moisture, chemical resistance, and durability. It’s recommended for components that are subjected to extreme environments and mechanical stress. 

In this article, we’ll detail what PETG is, its application, and five key things that you need to know to use it in your 3D prints effectively. 

Things To Know Before Using PETG for Mechanical Parts

In 3D printing, PETG is used to create mechanical parts due to its strength, durability, resistance to warping, and tolerance for high temperatures. 

PETG’s resistance to solvents, heat, and impacts provides varied applications across a wide range of industries, from packaging electronic insulators to 3D printing. Its increased popularity in 3D printing is primarily due to the glycol addition, which solves previous problems common in its predecessor (PET), such as overheating and fragility. 

PETG is also associated with a good deal of adhesion between printed layers in 3D printing, which means the final product will have minimal deformation. This coupled with chemical resistance, resistance to low temperatures, and its durability has seen PETG rise to become the preferred filament in 3D printing. 

However, using PETG is not as straightforward as other filaments. So, let’s cover five key things you need to know before using PETG for mechanical parts. 

1. Set the Right Temperature 

PETG is lauded for high-temperature tolerance as it has a much higher melting point when compared to other filaments, such as PLA. So, it’s vital to set the build plate temperature and extruder temperature accordingly. 

Some 3D printers may have built-in PETG settings, but you should always double-check those against the manufacturer’s recommendations with each new brand you use. 

If your printer does not have such settings, you’ll need to change them manually. Again, it’s always best to check the recommended settings and temperatures before printing with a new filament. That said, there are some standard temperature ranges to keep in mind. 

The recommended heated bed temperature for PETG is: 

  • 80°C plus or minus 10 degrees (70 to 90°C)
  • 176°F plus or minus 18 degrees (158 to 194°F) 

You should set the extruder temperature to: 

  • 250°C plus or minus 10 degrees (240 to 260°C)
  • 482°F plus or minus 18 degrees (464 to 500°F)

This is crucial because improperly setting bed and extruder temperatures may result in heat creeping. This can lead to compromised or deformed prints or early swells. 

I recommend keeping this temperature within the required parameters, though starting at the lower end is best. Then, be sure that the heated bed and extruder temperatures are not set too high. 

2. For Best Results, Use a Fan

While PETG has a tremendous upside when used in making mechanical parts, we recommend introducing a cooling fan to your setup. This is especially so for the first layer. 

The cooling fan helps to ensure that your print work is rapidly cooled. Consequently, your final product will have high print details and minimal blobs or stringing. 

However, for the initial layers of your print, avoid using the fan because this will help enhance layer adhesion. From there, keep the fan at 50% to ensure high details for the final prints. 

3. PETG Is Easily Recyclable 

PETG is easily recyclable, so you should pay keen attention to recycling any PETG material used during the 3D process. 

It’s important to remember that just like other plastics, PETG will take a long time to decompose, which may have significant and negative environmental impacts. 

Additionally, due to this long period before decomposition, most plastic waste washes into the oceans, with negative consequences. So, wherever possible, try to cut down on wasted materials.

PETG is also BPA-free, which means that you do not have to worry about handling the filament without gloves. 

4. PETG Helps Withstand Mechanical Stress

Admittedly, there is no shortage of filaments that you can use for 3D printing. However, it is essential to appreciate that if parts may be subjected to significant mechanical stress, you’ll need to use something more robust than standard PLA. 

PETG is ideal for such parts due to its exceptionally robust material, high chemical and heat resistance, and flexibility. In addition, PETG stands up to immense mechanical stress, so you can rest assured of the reliability of the 3D-printed parts. 

PETG also has high moisture resistance when compared to other alternatives such as PLA, which adds to its mechanical properties. 

Note that PETG is ideal for creating long-lasting mechanical parts and manufacturing tools because it is perfect for environments where chemical and heat resistance is needed. 

5. Use a Build Plate Adhesive for Best Results 

Adding an adhesive helps keep the print bed from curling, which is a common challenge when 3D printing with PETG. Problems with print bed adhesion can be minimized by adding a layer of glue. 

Final Thoughts

PETG is an excellent filament to use when printing mechanical parts. Its high heat resistance, moisture resistance, chemical resistance, durability, flexibility, and anti-warping properties help enhance its level of mechanical stress tolerance. 

PETG is also recyclable and BPA-free, making it ideal for environmental and health-conscious consumers. Just take the necessary steps to recycle the PETG after use. 

With all these properties, it is easy to see why PETG has become one of the most popular filaments in 3D printing.

Written by:
Ben
Last updated:
11/16/2023

About Ben

I started 3D printing since 2013 and have learned a lot since then. Because of this I want to share my knowledge of what I have learned in the past years with the community. Currently I own 2 Bambulab X1 Carbon, Prusa SL1S and a Prusa MK3S+. Hope you learn something from my blog after my years of experience in 3D printing.