Echoing all the comments here calling this bill absolutely ludicrous. If you're determined to make a gun, and determined to 3d print it, then making a diy machine is as easy as ordering a few stepper motors, some linear extrusion and a motor control board. Are they gonna background check before you buy those too? What about a lathe? Or any steel tube? Or a hacksaw FFS. Unabomber made his pistol from broken car parts and a goddamn hand drill:

" [A] few days ago I finished making a twenty two caliber pistol. This took me a long time, for a year and a half, thereby preventing me from working on some other projects I would have liked to carry out. Gun works well and I get as much accuracy out of it as I'd expect for an inexperienced pistol shot like me. It is equipped with improvised silencer which does not work as well as I hoped. At a guess it cuts noise down to maybe one third. It is said that it is easy for machinist to make a gun, but of course I did not have machine tools, but only a few files, hacksaw blades, small vice, a rickety hand drill, etc. I took the barrel from an old pneumatic pistol. I made the other parts out of several metal pieces. Most of them come from the old abandoned cars near here. I needed to make the parts with enough precision but I made them well and I'm very satisfied. I want to use the gun as a homicide weapon"

You know what you can't easily manufacture at home? Bullets.

Draw your own conclusions on why that isn't up for regulation here