Functional 3D printing strong objects
This is a method I use to build function 3D parts, mainly for stuff that flies and crashes. Choosing your orientation for strength and then combining two objects printed in different orientations will dramatically increase the strength of your object. These are just test prints I'm creating to verify a construction idea for a somewhat complex build of an aerodynamic based top speed quadcopter.
I've used this technique to print lightweight center sections and motor mounts for my own tube frame quadcopters. I have a 5" quad with 1408 motors that weighs 133g with props I built with this method using CF re-enforced nylon. The CF tubes are now the weakest part of my builds and break before anything 3D printed.