[lemonwaterlime]

Taken at face value, this is engineering negligence. I've done industrial design with plastics and 3D printed parts. Regardless of the forming techniques, with plastics you still need to consider properties like minimum melting temperatures, tensile stress, and so forth. Then you must test that rigorously. This is all standard procedure. That information is in the data sheet for the material.

I did a quick search and found that many plastics are governed by ISO 11357 test standard [1]. Some of the plastics I have worked with used this standard.

A spec sheet for that material is here [2].

[1]: https://www.iso.org/standard/83904.html

[2]: https://um-support-files.ultimaker.com/materials/1.75mm/tds/...

[ToucanLoucan]

Also, strictly as a combo 3D-printing and engine enthusiast: Never with a GUN to my head would I install 3D printed parts in a CAR engine, let alone in an aircraft engine. This is spectacularly poor judgement on the part of the owner.

[jacquesm]

Then you are not up to speed with what the 3D printing world has to offer. You can 3D print full metal stress free parts and chances are very high that if you have flown in an airplane in the last five years that some of the parts of that plane (and I'm not talking about trim here) were made using additive processes.

Rocket engines can be 3D printed, in fact there are some engines that can only be made using that kind of technique due to internal structures.

[SoftTalker]

Depends. Some older or rare cars have no source for parts. 3D printing has been a boon to keeping them operating. However you absolutely have to use appropriate materials to avoid problems or failures, and know where it isn't feasible.

[shmeeed]

FWIW, I wouldn't hesitate to install a 3D printed air-filter housing in my car, if I had printed it myself out of e.g. PAHT or sourced it from a trusty vendor. It's not rocket science, just engineering.

[PunchyHamster]

Well, there are more and less important parts of the car. I wouldn't bat an eye for 3d printed dash parts or the extreme example, a cup holder, but on flip side anywhere where there is heat is potentially bad for anything 3d printed with heat that's not metal or some hard to print high temp stuff, and anywhere where mechanical robustness = safety is spot where you want something very well tested, not "I printed it and it looks light".

[bsder]

> Never with a GUN to my head would I install 3D printed parts in a CAR engine, let alone in an aircraft engine.

The fabrication technology doesn't matter. The qualification process, on the other hand ...

This is the primary reason why I never got a pilot's license. I suspect I would spend far too much time making sure the maintenance was up to standard and far too little actually enjoying flying.

[Aeolun]

I wouldn’t be that absolute, but not until Boeing and Airbus use them in their aircraft on a regular basis.

[cibyr]

I'm sure it's fine you do it properly ([1] for example). The issue here was the utter lack of engineering, not the specific manufacturing technique (although those do seem to be highly correlated, due to low-end 3D printing having become very cheap and easy).

[1] https://www.youtube.com/watch?v=rV74KhPNg1w