DEFCAD

Notes:
This is a sound moderator aka “silencer” for an airgun or paintball gun. Pump-up airguns in particular make a lot of noise as the air rushes out, and the moderator cotains a series of what are called “K Baffles” (see cutaway one in the photo) that slow it down so that it does not make a sharp >Crak!< The pellet goes unimpeeded down the middle, and may even slightly gain velocity. This design is remarkably efficient.

Supersonic projectiles will always go crack anyway and a silencer is pretty pointless with them. Firearms are likely to blow the silencer to bits.

Download:
http://defcad.org/stl/files/Sound_Moderator_MK2.stl

Android App Testers Needed

admin — Sun, 23 Dec 2012 08:15:53 +0000

Purpose:
- Beta test the app on different Android phones and platforms
- Collect feedback from beta testing to help further develop the app
- Discuss new ideas on how to better the app
- Integrate DEFCAD into the Defense Distributed app

Requirements:
- Android phone
- Can test an app once a week (~1 hour)

Status:
CLOSED – not accepting anymore testers at the moment!

Email hmk@defdist.org the following info:
1. What phone do you have?
2. What version of Android are you running?
3. Which days are best for communicating online and beta testing?
4. Have you already installed the Defense Distributed app?
5. Do you ever scan QR codes?

Triple Shotshell Carrier

admin — Thu, 20 Dec 2012 14:48:33 +0000

Author:
SFE_Tim

Download:
http://defcad.org/wp-content/plugins/download-monitor/download.php?id=30

AR-15 Reinforced Lower Receiver

admin — Thu, 20 Dec 2012 14:46:07 +0000

Author:
haveblue

Notes:
This receiver is based on the IGES file from Justin Halford’s superb CNC Gunsmithing site: cncguns.com/downloads.html

Download:
http://defcad.org/wp-content/plugins/download-monitor/download.php?id=20

AR-15 Grip

admin — Thu, 20 Dec 2012 14:34:28 +0000

Author:
7777773

Notes:
Here’s my contribution to the fun. A grip for the AR-15. Grips are a highly personal bit…

Download:
http://defcad.org/wp-content/plugins/download-monitor/download.php?id=11

License:

AR-15 Grip (7777773) / CC BY-SA 3.0

“Can a 3D printer make guns?”

admin — Wed, 19 Dec 2012 19:48:02 +0000

3-D printer MakerBot cracks down on blueprints for gun parts
By Julianne Pepitone

NEW YORK (CNNMoney)
In the wake of the second-deadliest school shooting in American history, 3-D printer company MakerBot is cracking down on downloadable designs for printable gun parts.

Like other 3-D printers, a MakerBot is a machine that creates physical objects. The printer uses a design file as a blueprint, then fabricates the item from layers of plastic material like powder or liquid. The technology has moved from the manufacturing world to an early-adopter customer base of hobbyists, who use the printers to create anything they can design: figurines, iPhone docks, coffee cup holders.

And, in theory, gun parts.

MakerBot runs a website called Thingiverse, which is a database of downloadable design files for a variety of 3-D printers on the market. The site’s terms of service have long prohibited “the creation of weapons,” but they were loosely enforced, and blueprints for gun parts were available until early this week — just a few days after the shooting at Connecticut’s Sandy Hook Elementary School. CNET was the first to spot MakerBot’s crackdown, saying it began on Tuesday.

MakerBot representative Jenifer Howard said no executives were available for an interview, but she provided a short statement saying that the company’s “focus is to empower the creative process and make things for good.”
Beyond that, MakerBot pointed to Thingiverse’s Terms of Service, which stipulate that users cannot “collect, upload, transmit, display, or distribute” any content that “promotes illegal activities or contributes to the creation of weapons, illegal materials or is otherwise objectionable.”

Those service terms “have been the same for quite a while and have not changed,” Howard said.
MakerBot’s crackdown comes amid a growing debate around the potential for 3-D printers to be used to create weapons. Plastic guns are currently illegal under the Undetectable Firearms Act of 1988, which prohibits guns that can’t be picked up by metal detectors and X-ray machines. The law expires at the end of 2013, and earlier this month Rep. Steve Israel, a Democrat from New York, announced legislation to renew the ban.

“Congress passed a law banning plastic guns for two decades, when they were just a movie fantasy. With the advent of 3-D printers these guns are suddenly a real possibility,” Israel said in a statement at the time.

Israel’s legislation came just five days after a group called Defense Distributed posted a YouTube video of a AR-15 assault rifle that included some 3-D printed parts. The group was able to shoot six rounds before the gun failed.

It’s part of Defense Distributed’s Wiki Weapon Project, which aims to “produce and publish a file for a completely printable gun — or as near to completely printable as actually possible with current technologies,” the group’s website says.

Defense Distributed tried to raise funds for the project earlier this year on Indiegogo, a crowdfunding site. Indiegogo suspended the campaign in August, citing “unusual account activity.” Since then, Defense Distributed has been collecting donations through its website and posting results of tests using printed gun parts.

Following the Thingiverse crackdown, which removed files the group had been using from the database, Defense Distributed posted a message saying it is “preparing an alternative upload site” and “will no longer develop with the Makerbot in mind.”

“How can this decision be described as anything but reactionary and paternalistic?” Defense Distributor founder Cody Wilson asked in an interview with CNNMoney. “Now in the MakerBot universe all objects are not created equal.”