Thingiverse Cracks Down on Firearm Parts

blog.makezine.com ^ | 20 December, 2012 | Sean Ragan

[marktwain]

This is the lower receiver of an AR-15 rifle, printed in fused plastic filament from a digital model that was, until this week, freely available for download on Thingiverse.

This part is significant because all other parts of the common rifle can be readily purchased in the open market. A person who builds a working lower receiver has, in the eyes of the state, essentially built a working AR-15. It is legal to do so for personal use (at least under US law), but until lately the required tools, time, and talent put the project beyond the reach of most casual tinkerers.

The rise of desktop manufacturing, however, may be set to change all that. Recently, a 3D printed AR-15 lower receiver made of fused plastic filament was demonstrated to fire and cycle six times before breaking.

Andy Greenberg over at Forbes has the story on the removal of this model, and other key firearms-related physibles, from Thingiverse. As of this writing, no official statement appears on either MakerBot’s or Thingiverse’s sites, though the action seems entirely consistent with Thingiverse’s established Terms of Use, which were updated following the the site’s first firearms controversy back in 2011 to include proscriptions against content that “contributes to the creation of weapons.”

Up to now, however, the policy has gone largely unenforced.

From the comments: Sean Ragan on December 20th, 2012 at 6:56 pm said:

I note, as an aside, that it just took me about 3 minutes to nab a torrent containing digital models of an AR-15 lower (and the parts for a 5-round magazine) from The Pirate Bay’s “physibles” section.

[RobinOfKingston]

Does the printer come in a box from ACME?

This is roughly analogous to Wilbur and Orville's first 3 or 4 hundred foot flight at Kitty Hawk.

[nomad]

Would it be possible to make that out of a melt-able plastic in photo negative reverse? I seem to remember a process known as lost wax molding in which the piece to be cast is molded in a wax compound and then encased in a ceramic. Its then heated to melt off the wax and the ceramic shape used as a mold for casting the object in metals.

[nomad]

Yes, see my post. It would be a simple matter of building a retort, obtaining a crucible, and buying the proper metal alloy.Even if it must be cast a bit heavier, like Hi-Point`s line, they work.

[nomad]

Research Hi-Point manufacturing out of Mansfield, Ohio. I believe they cast their major components, very little machining left. Properly thought out, this could be a major, but doable, home project.Something that entails only a fully adjustable, table equipped drill press and hand finishing with a Dremmel tool.

[TArcher]

Err umm, sorry - I seem to have lost my crucible in an unfortunate boating accident.