alt Hacker NewsIt's not the "3D printed" aspect of the part that's driving the failure, it's that it's made out of thermoplastic. An injection molded part in this situation[1] would likely have failed in the same way.
[1] It's not clear what the source of the heat was or where this was in the motor enclosure. But yeah, one needs to be careful with structural plastic near running engines!
Thermoplastic is the problem here. There are plenty of thermoset and other kinds of plastics that handle heat well and don’t soften with heat in normal ranges. 3d printed thermoplastics typically need to be liquid at <300 C so the glass transition usually is closer to 200 or even less. Definitely not suitable for the engine bay.