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.