I just ran across this: http://www.thingiverse.com/thing:11669
The short-version is that, with a 3D printer, you can manufacture your own lower at home, no background checks, no nothing.
The functionality issues are almost as interesting as the legality issues. It seemed to me to be a subject a few here would be interested in discussing.
3D printing is still in the infant stage, but I see a great deal of potential there. I can Really see someone printing out a few Generation-1 PS90 internal components to replace their Generation-3’s.
If it were up to me, I’d probably make a few changes in a lower made from ABS rather than aluminium such as reinforcing the pin holes or perhaps making the holes large enough to accept larger, metal bushings which would then hold the pins.
I printed the upper and lower on one of my 3D Printers. No testing yet!
I did cut a lower so I can access the TG for detailed modifications.
Tagged:
This is interesting, more pics & info please. 
My first question is, didn’t you just manufacture two illegal firearms?
as far as legality goes, would these fall under the same rule as the 80% lowers?
ETA: This is awesome.
This 3-D printing is new to me.
And frankly my mind is spinning right now. Ohhh the court battles to come 
Printing guns! Awesome! My dumb printer only makes words and pictures!
Can I print a Ferrari too?!?!
That’s clever.
How about hookers?
What kind of 3D printer is it? I’m familiar with stereolithography, but I’ve done very little research on 3D printing. This could be very useful in one of my shops.
From Wikipedia:
“Three-dimensional printing makes it as cheap to create single items as it is to produce thousands and thus undermines economies of scale. It may have as profound an impact on the world as the coming of the factory did…Just as nobody could have predicted the impact of the steam engine in 1750, or the printing press in 1450, or the transistor in 1950. It is impossible to foresee the long-term impact of 3D printing. But the technology is coming, and is likely to disrupt every field it touches”
The possabilities here, especially as this technology progresses is making my head spin. And the future legalities regarding regulated products and counterfiet products is mind boggling to me. The future of this is almost to big to wrap your head around.
I could go for a couple of 7 of 9’s in the holodeck for a few hours! 
THAT aside, I’m tagging this too for the range tests!
Why? It’s no more illegal to “print” a lower than it is to machine one for yourself
Isn’t it a controlled item regardless of how or who manufactures it, though?
The one I use at work is capable of printing casting molds that you can cast aluminum in!
Yes. But it’s not against the law to fabricate receivers without a license for your own personal use. The home fabricator cannot offer them for sale or give them away
I had no idea the technology was quite this far along, and to be honest, I hadn’t even considered that components this complex could even be rendered. I don’t know how functional these uppers and lowers will prove to be as firearms, but it isn’t difficult to see all kinds of potential as training aids, vise blocks and fitting jigs.
I can see the puzzled expressions on the faces of the airsoft community already.
Now, where are the G-36C plans? 
AC
Maybe more importantly…how does this ABS plastic react to oil-based lube?
This is going to change a lot of things. Still young but the possibilities are very cool.
You can even scan something with moving parts, print it, and you’ll have moving parts. Like on a wrench the little wheel to adjust the wrench…it comes out of the printer in fully working condition as a separate piece from the rest of the wrench…