It’s kinda a lot more difficult to build a proper rifle with old fashioned tools. You need a workshop and quite some money for that stuff.

It's kind of not, and you don't. You're still reliant on metal for any actual parts involved in the firing process. You still cannot 3d print a barrel you want to use more than once or with any sort of accuracy.

Oh, and actually quite some knowledge if you want to get something that actually works more than once and shoots straight.

Right, which is why 3d printers aren't that gr... oh, wait, you thought you were talking about milling machines. Nah dude, 3d printers are a fucking whore and a bitch to get good parts off of. They're finicky as shit. You can EASILY have a 30 hour long print shit itself at the last minute and render the whole thing unusable. It doesn't matter what kind of printer you're using, it WILL wreck your life at some point. Unless, of course, you're using a six-figure production machine at which point your entire money argument gets skullfucked.

And did I mention that this stuff is expensive?

No, it isn't. You can get a mill for under a grand if you look around. Hell, find the right old timer looking to get rid of his gear and you'll probably get some good tools as well. Not that this matter, because when you're trying to improvise weapons A FUCKING DRILL PRESS is more than enough to get the job done for most operations. Whatever your shop is doesn't goddamn matter when the gun only has to operate for a handful of shots.

I know, because I have such a fancy workshop.

Well obviously you're a fucking terrorist and need to register all of your tools. Mills, lathes, any sort of welding or sheet metal equipment, all of this can be used in the manufacture of firearms and since you're piss-pants bitchass scared of plastic I can only assume that extends to the ability to manufacture real live firearms, right?

RIGHT? YA FUCKING BRAINDEAD HYPOCRITE? You going to register your fucking mill with the government so they know you aren't a terrorist? ARE YOU NOW OR HAVE YOU EVER BEEN A MEMBER OF THE COMMUNIST PARTY?

I’d gladly be on a list of 3D printer owners, just for those Nazi fucks to have another obstacle and another “contact point” with authorities where they can be caught.

That's because you're a moron.

Here's your gold star, 3d printer boy, please board the train and don't cry too much.