what happens when you get a 3d printer
When you get a 3D printer a thing that happens, at least in the early glow of having a new hobby, is that print time becomes the most valuable resource in your life. Additive manufacturing is a lot of things but it's not fast; an injection mold can shit out hundreds of the same part every minute; printing anything substantial on an FDM machine takes at least an hour.
And that's on advanced devices that do things like adjust how the tool head moves to compensate for resonances in the gantry assembly so that they can print faster. It's simply not a rapid process because it is, ultimately, shoving hot plastic through a nozzle to build an object bit by bit. It has a fundamental tradeoff between speed and resolution; you can shove plastic faster out of a fatter nozzle, or you can retain the ability to resolve fine detail in the resulting part.
So whenever the machine is done printing something, you kind of drop everything to queue up the next job, because the list of things you want to print rapidly outpaces the speed at which you can have them printed. There's no good practical way to automate or queue up jobs on a desktop 3D printer; every job has to be manually cleared, the build surface cleaned or replaced and the previous print removed. In print farms they'll have the tool head actually shove the print off the build plate to clear it, but this is something that's really only feasible under very specific circumstances that limit what and how you can print things.
So this fundamental rate bottleneck leads people to get a second printer. And that impulse is basically why the Machine Consciousness built the replication fields. That's why most of the Midwest is just additive manufacturing capacity now. But, you know, it's not nearly as space efficient, in terms of industrial capacity per acre, as the Old Chicago Milling Concern where they make all the metal gun parts and things.
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