Filament Heat Test PLA vs PETG vs PAHT

Brian
Aug 26
2 min read

Updated: Aug 27

Have you ever heard the saying, "One test is worth a thousand expert opinions"? In this blog post, I'm putting that to the test in the most literal sense by conducting a heat test on sunglasses made from three different 3D printing filaments: PLA, PETG, and PAHT-CF, plus a control pair of store-bought sunglasses.

Watch Our Full Review Here

The Setup

For this experiment, I 3D printed sunglasses using the three filaments mentioned above. Each filament is designed to handle different temperature levels:

PLA (Polyactic Acid): Prints around 210°C and softens at about 60°C.
PETG (Polyethylene Terephthalate Glycol-modified): Prints at about 240°C and softens at 80°C.
PAHT-CF (Polyamide High Temp Carbon Fiber): Prints at a robust 270°C and softens at approximately 120°C.

I also included a regular pair of sunglasses as a control in the experiment to see how they would hold up in extreme heat.

The Experiment

All the sunglasses were placed on my car dashboard on a scorching day. The outside temperature was 105°F, but unfortunately, I couldn't record the exact inside temperature as my thermometer decided to quit on me due to the heat.

The Results

Initially, you might expect the higher temperature filaments to perform better, but that wasn't entirely the case. Here’s what happened to each:

Control Sunglasses: As expected for my $100 investment, they survived without any effect.

PLA Sunglasses: The PLA shades turned out soft to the touch but maintained a mostly intact frame. You could bend them slightly, causing a permanent deformation. However, they held their shape enough to still function as sunglasses, albeit with some degradation over time.

Softening and Slight Warp to PLA
PETG Sunglasses: To my surprise, PETG was a disaster. I had relied on its supposed heat tolerance for years, yet under this heat test, they ended up looking like a melted pile of spaghetti on my dashboard.
Complete Destruction of PETG
PAHT-CF Sunglasses: These carbon fiber glasses were the clear winners. They remained rock solid, unwarped and unbent, despite attempts to manipulate them. They seemed to judge the failures of the other materials without flinching.
PAHT-CF Unaffected Due to Temperature

Conclusion

In conclusion, the PLA softened, PETG was utterly destroyed, and the PAHT-CF stayed unaffected. These results were startling, partially debunking the initial assumptions about temperature resilience based on printing temperatures. Was this result surprising to you? If so, drop a comment below! And if you'd like me to test more filaments, let me know that too. For those interested, the 3D printed sunglasses models are available at Maker World and Thingiverse. That’s all for today. Thanks for reading and God bless.