UPDATE: I deleted the original post and adding this:
3D printing with filaments is not an exact, repeatable process - you need to save your models as they were when you printed them, If you change the settings in the slicer, change material, change nozzle size, etc. your tight tolerances are most likely to fall apart - so you need to manage your models differently than would manage other abstract objects.
There might be an entire ecosystem to be built around this fact and FourOh-LLC is betting it is going to be. Dozens or even hundreds if not thousands of variations in customization to the rails system I am going to be presenting provides the proof, the use cases. This rail system is used to tranport flexible MRI PCBs which wrap around the limbs of a person: the rails are stored until they are needed, then stored again. Weighing around 40 lbs at 12 feet long these are highly customized, one-of the kind industrial equipment.
Since we are MESA members now I am going to be referring people to these channels, and as always my focus remains LOCAL to Kane County, Illinois. The local industrial supply chain association we are building going to be explained on this forum / channel, while the other forums / channels remain invisible to the rest of the World.
Onto the original post:
The hinge I posted before is part of a larger construct, a 12.3" rail system built to be super-light-weight, and all broken parts of it maybe replaced by buying a COTS (commercial off-the shelf) and by 3D printing the 3D-printed part(s). Pretty straight-forward, functional, basic, valid engineering.
The "real" challenges of course is in making the rails ready to be wired-up for automation. So the holes in the 3D-printed parts are there - but if you need to replace that extruded with aluminum good luck finding a 5-hole at 20 mm.
So, you CAN and SHOULD 3D-print the broken part. Corporations with a lot of production capacity sacrifice this type of customization, where you are able to pull a hundred conductor / square-inch for the cheap, at will.