{"id":1631,"date":"2014-05-05T20:49:52","date_gmt":"2014-05-06T02:49:52","guid":{"rendered":"http:\/\/haveblue.org\/?p=1631"},"modified":"2014-05-05T20:49:52","modified_gmt":"2014-05-06T02:49:52","slug":"gunsmithing-with-a-3d-printer-part-5","status":"publish","type":"post","link":"https:\/\/haveblue.org\/?p=1631","title":{"rendered":"Gunsmithing with a 3D Printer &#8211; Part 5"},"content":{"rendered":"<p>\t\t\t\tI realized it has been over a year since I last wrote on the subject (though to be fair, it seems it has been about that much time since I&#8217;ve written much of anything substantial).\u00a0 Since I last addressed the topic in March of 2013, the apex of the &#8220;3D printed gun&#8221; story has been reached, and media interest in the concept has subsided.\u00a0 Just as promised, <a href=\"http:\/\/defensedistributed.com\">Defense Distributed<\/a> successfully created an entirely 3D printed firearm (save for a roofing nail used as a firing pin), proved the functionality, and released the STL files.<\/p>\n<p>Naturally, I downloaded the files as soon as they were released last May.\u00a0 Ever since Defense Distributed had stated their goal of designing, testing, and proving the possibility of a 3D printed gun, I had pondered how to actually achieve such a goal.\u00a0 I had my own ideas in mind, and figured I could probably design something workable in a weekend, but testing and refining the design is something else &#8211; CAD is easy, but proving the model is hard.\u00a0 My own line of thinking revolved around using a <a href=\"http:\/\/en.wikipedia.org\/wiki\/.410_bore\">.410 shotshell<\/a> as the intended cartridge, due to its extremely low pressure in comparison with other rounds.\u00a0 This would have entailed building a fairly large gun with a rather long barrel (over 18 inches so as to not run afoul of the <a href=\"http:\/\/en.wikipedia.org\/wiki\/National_Firearms_Act\">NFA<\/a>), and would have taken quite a while to print.\u00a0 As it turned out, DD came up with a remarkably elegant gun, far more refined than what I myself had in mind &#8211; something that stayed true to the intent of pushing the limits of 3D printing.\u00a0 When I say elegant, I mean elegant in the Unix sense &#8211; not something that is beautiful to behold in an artistic manner, but something that has raw simplicity and efficiency in design and operation.<\/p>\n<p>DD called their creation the <a href=\"http:\/\/en.wikipedia.org\/wiki\/Liberator_%28gun%29\">Liberator<\/a>, an homage to the <a href=\"http:\/\/en.wikipedia.org\/wiki\/FP-45_Liberator\">FP-45 Liberator<\/a> of WWII, an equally simple, straightforward pistol that was intended to be airdropped into occupied Europe for partisans to use in resistance of German forces.\u00a0 The DD version is much chunkier in construction, but shares many of the same design intents &#8211; a gun that is able to fire a single shot with a centerfire metallic cartridge with as little mechanical complexity possible.<\/p>\n<p>To this end, the Liberator is an impressive piece of work.\u00a0 It consists of only a handful of 3D printed components:<\/p>\n<ul>\n<li>receiver<\/li>\n<li>barrel<\/li>\n<li>breech block<\/li>\n<li>grip<\/li>\n<li>hammer<\/li>\n<li>trigger<\/li>\n<li>2 hammer springs<\/li>\n<li>trigger spring<\/li>\n<li>firing pin<\/li>\n<\/ul>\n<p>Plus a few pins that hold everything together.\u00a0 Of these, only the firing pin itself is metal and is actually a roofing nail &#8211; since the firing pin needs to impact the cartridge <a href=\"http:\/\/en.wikipedia.org\/wiki\/Primer_%28firearm%29\">primer<\/a> and deform it enough to crush the compound between the primer&#8217;s cup and anvil, material hardness is a key consideration for the firing pin (and is a material property that escapes the current capabilities of FDM printing technology).<\/p>\n<p>Since I had a number of journalists ask me for my take on the Liberator, I decided to print one for myself in order to give an accurate appraisal of the design.\u00a0 My friend Joe (not his real name) was also interested in building and testing one to make a proper evaluation, so we collaborated on doing a proper test shortly after the design was released.<\/p>\n<p>I opted to use up the rest of my MG47 filament for the various Liberator parts.\u00a0 Unfortunately, I lost extrusion halfway through printing the receiver:<\/p>\n<p><a href=\"https:\/\/i0.wp.com\/haveblue.org\/wp-content\/uploads\/2014\/02\/half-receiver-print.jpg\"><img data-recalc-dims=\"1\" loading=\"lazy\" decoding=\"async\" class=\"alignnone size-full wp-image-1686\" title=\"half receiver print\" src=\"https:\/\/i0.wp.com\/haveblue.org\/wp-content\/uploads\/2014\/02\/half-receiver-print.jpg?resize=614%2C532\" alt=\"\" width=\"614\" height=\"532\" \/><\/a><\/p>\n<p>Rather than re-print the entire thing (which was over 30 hours), I decided to place the part in the mill vise and plane off the top, then glue on a replacement top half.<\/p>\n<p><a href=\"http:\/\/haveblue.org\/wp-content\/uploads\/2014\/02\/half-receiver-print.jpg\"><\/a><a href=\"https:\/\/i0.wp.com\/haveblue.org\/wp-content\/uploads\/2014\/02\/planing-liberator-top.jpg\"><img data-recalc-dims=\"1\" loading=\"lazy\" decoding=\"async\" class=\"alignnone size-full wp-image-1687\" title=\"planing liberator top\" src=\"https:\/\/i0.wp.com\/haveblue.org\/wp-content\/uploads\/2014\/02\/planing-liberator-top.jpg?resize=614%2C472\" alt=\"\" width=\"614\" height=\"472\" \/><\/a><\/p>\n<p>I took the opportunity to also glue in a metal block for compliance with the <a href=\"http:\/\/en.wikipedia.org\/wiki\/Undetectable_Firearms_Act\">Undetectable Firearms Act<\/a>.\u00a0 I bought some 1&#8243; square steel bar and sawed a piece off the end, then found a little bit of scrap to fill in the sides.\u00a0 All told, I had 147 grams of steel, which should be more than sufficient to satisfy <a href=\"http:\/\/www.law.cornell.edu\/uscode\/text\/18\/922\">922<\/a>(p) (the specific section of US law codifying the UFA).<\/p>\n<p><a href=\"https:\/\/i0.wp.com\/haveblue.org\/wp-content\/uploads\/2014\/02\/ufa-block-epoxy.jpg\"><img data-recalc-dims=\"1\" loading=\"lazy\" decoding=\"async\" class=\"alignnone size-full wp-image-1688\" title=\"ufa block epoxy\" src=\"https:\/\/i0.wp.com\/haveblue.org\/wp-content\/uploads\/2014\/02\/ufa-block-epoxy.jpg?resize=614%2C461\" alt=\"\" width=\"614\" height=\"461\" \/><\/a><\/p>\n<p>Insight is a powerful piece of 3D printing software, and I was able to go back to my sliced version of the receiver and delete all the layers from the file that I had already successfully printed.\u00a0 This allowed me to print just the upper half of the receiver, and I printed a barrel at the same time for good measure.<\/p>\n<p><a href=\"https:\/\/i0.wp.com\/haveblue.org\/wp-content\/uploads\/2014\/02\/replacement-top.jpg\"><img data-recalc-dims=\"1\" loading=\"lazy\" decoding=\"async\" class=\"alignnone size-full wp-image-1689\" title=\"replacement top\" src=\"https:\/\/i0.wp.com\/haveblue.org\/wp-content\/uploads\/2014\/02\/replacement-top.jpg?resize=614%2C452\" alt=\"\" width=\"614\" height=\"452\" \/><\/a><\/p>\n<p>Note that the .STL file for the Liberator barrel that was originally released is a smoothbore with no rifling (just like the original WWII FP-45 Liberator).\u00a0 This theoretically makes it an AOW (<a href=\"http:\/\/en.wikipedia.org\/wiki\/Title_II_weapons#Any_Other_Weapon\">Any Other Weapon<\/a>) under the 1934 <a href=\"http:\/\/en.wikipedia.org\/wiki\/National_Firearms_Act\">National Firearms Act<\/a> (NFA).\u00a0 The definition of an AOW is rather convoluted (and somewhat contested, given <a href=\"http:\/\/www.titleii.com\/bardwell\/us_v_davis2.txt\">U.S. v. Davis<\/a>), but it is intended as a catch-all category for firearms not otherwise defined by other categories (hence, &#8216;Any Other&#8217;).\u00a0 A pistol or revolver with a smooth bore is generally considered an AOW, and for an unlicensed individual to make one, they need to submit a <a href=\"http:\/\/www.atf.gov\/files\/forms\/download\/atf-f-5320-1.pdf\">Form 1<\/a> to the ATF along with fingerprint cards, a passport photo, $200, and a sign-off from their chief law enforcement officer.\u00a0 In other words, if you want to try printing a Liberator and don&#8217;t want a lot of hassle, make sure the barrel has rifling in it to avoid trouble.\u00a0 Even modern reproductions of the FP-45 Liberator have tiny (and ineffective) rifling grooves in order to remain compliant.<\/p>\n<p><a href=\"https:\/\/i0.wp.com\/haveblue.org\/wp-content\/uploads\/2014\/02\/rifling.jpg\"><img data-recalc-dims=\"1\" loading=\"lazy\" decoding=\"async\" class=\"size-full wp-image-1691 alignnone\" title=\"rifling\" src=\"https:\/\/i0.wp.com\/haveblue.org\/wp-content\/uploads\/2014\/02\/rifling.jpg?resize=614%2C640\" alt=\"\" width=\"614\" height=\"640\" \/><\/a><\/p>\n<p>I made sure to add rifling to the print itself, as rifling it afterwards would necessitate equipment that I simply don&#8217;t have (but would love to <a href=\"https:\/\/smartflix.com\/store\/video\/320\/Bill-Webs-Rifle-Barrel-Making-Machine\">build<\/a> someday).<\/p>\n<p><a href=\"https:\/\/i0.wp.com\/haveblue.org\/wp-content\/uploads\/2014\/02\/epoxied-halves.jpg\"><img data-recalc-dims=\"1\" loading=\"lazy\" decoding=\"async\" class=\"alignnone size-full wp-image-1690\" title=\"epoxied halves\" src=\"https:\/\/i0.wp.com\/haveblue.org\/wp-content\/uploads\/2014\/02\/epoxied-halves.jpg?resize=614%2C472\" alt=\"\" width=\"614\" height=\"472\" \/><\/a><\/p>\n<p>Although the top half of the receiver printed without loss of extrusion, there was still a significant amount of warp on the bottom.\u00a0 I opted to mix up a batch of epoxy with <a href=\"http:\/\/en.wikipedia.org\/wiki\/Microballoons\">microballoons<\/a> and <a href=\"http:\/\/en.wikipedia.org\/wiki\/Colloidal_silica\">colloidal silica<\/a> (a thickener) to glue the two halves together.<\/p>\n<p><a href=\"https:\/\/i0.wp.com\/haveblue.org\/wp-content\/uploads\/2014\/02\/mg47-liberator.jpg\"><img data-recalc-dims=\"1\" loading=\"lazy\" decoding=\"async\" class=\"alignnone size-full wp-image-1692\" title=\"mg47 liberator\" src=\"https:\/\/i0.wp.com\/haveblue.org\/wp-content\/uploads\/2014\/02\/mg47-liberator.jpg?resize=614%2C409\" alt=\"\" width=\"614\" height=\"409\" \/><\/a><\/p>\n<p>I didn&#8217;t actually print the needed pins and just used some spare sections of metal tubing instead.<\/p>\n<p><a href=\"https:\/\/i0.wp.com\/haveblue.org\/wp-content\/uploads\/2014\/02\/lulzliberator1.jpg\"><img data-recalc-dims=\"1\" loading=\"lazy\" decoding=\"async\" class=\"alignnone size-full wp-image-1694\" title=\"lulzliberator1\" src=\"https:\/\/i0.wp.com\/haveblue.org\/wp-content\/uploads\/2014\/02\/lulzliberator1.jpg?resize=614%2C515\" alt=\"\" width=\"614\" height=\"515\" \/><\/a><\/p>\n<p>Meanwhile, Joe used his <a href=\"https:\/\/www.lulzbot.com\/\">Lulzbot<\/a> to create a remarkably robust receiver out of standard PA-747 filament.\u00a0 He had tweaked his machine to provide extraordinarily dense prints with virtually no porosity.\u00a0 We decided to test out his version to determine just how well the design works, its durability, and to get some velocity data to determine actual muzzle velocity.\u00a0 Additionally, news stories on the Liberator seemed to generally claim that a $10,000 (or more) 3D printer was required to print the Liberator.\u00a0 We wanted to dismiss this notion and show that even a $1000 printer is perfectly capable of printing high strength objects.<\/p>\n<p><a href=\"https:\/\/i0.wp.com\/haveblue.org\/wp-content\/uploads\/2014\/04\/test-setup.jpg\"><img data-recalc-dims=\"1\" loading=\"lazy\" decoding=\"async\" class=\"alignnone size-full wp-image-1760\" title=\"test setup\" src=\"https:\/\/i0.wp.com\/haveblue.org\/wp-content\/uploads\/2014\/04\/test-setup.jpg?resize=614%2C427\" alt=\"\" width=\"614\" height=\"427\" \/><\/a><\/p>\n<p>In mid-May of last year, we met up to actually perform the testing.\u00a0 Our test rig consisted of an <a href=\"http:\/\/www.8020.net\/\">80\/20<\/a> frame to actually mount the Liberator to, which itself we clamped to a folding table.\u00a0 In front of the test rig, we set up the sensors for my <a href=\"http:\/\/www.pact.com\/\">PACT chronograph<\/a> (used to measure the speed of the fired bullet).\u00a0 For safety, we used a 30 foot length of paracord to pull the trigger.\u00a0 Note also that we used machine screws to actually mount the breech block within the receiver, rather than 3D printed pins.\u00a0 Additionally, Joe&#8217;s barrel was slightly longer than the published Liberator barrel.<\/p>\n<p>We had a great deal of difficulty getting the gun to fire in the first place, making nearly ten attempts to get it to go &#8216;bang&#8217;.\u00a0 The first issue was getting the sear tail to actually release the hammer, so we replaced the trigger bar with one printed on my machine.\u00a0 After this, the primer was indeed getting struck, but it did not seem to be igniting &#8211; we replaced the springs with ones from my machine as well.\u00a0 We would wait 30 seconds after each attempt in case there was a <a href=\"http:\/\/en.wikipedia.org\/wiki\/Hang_fire\">hangfire<\/a> (thankfully we never had one during the testing).\u00a0 We wondered if <a href=\"http:\/\/en.wikipedia.org\/wiki\/Headspace_%28firearms%29\">headspacing<\/a> could be an issue, so we pulled Joe&#8217;s barrel and put in one that I had printed on my machine.\u00a0 We also replaced the .380 cartridge we had been using with a fresh one in case it was a dud.<\/p>\n<p><a href=\"https:\/\/i0.wp.com\/haveblue.org\/wp-content\/uploads\/2014\/04\/blown-barrel.jpg\"><img data-recalc-dims=\"1\" loading=\"lazy\" decoding=\"async\" class=\"alignnone size-full wp-image-1761\" title=\"blown barrel\" src=\"https:\/\/i0.wp.com\/haveblue.org\/wp-content\/uploads\/2014\/04\/blown-barrel.jpg?resize=614%2C444\" alt=\"\" width=\"614\" height=\"444\" \/><\/a><\/p>\n<p>Our next attempt did indeed go &#8216;bang&#8217;, and there was very little of the barrel left in the receiver.\u00a0 My Stratasys FDM 1600 still has a bit of porosity in its output, and I hadn&#8217;t done a solvent vapor treatment on the barrel as was recommended by Defense Distributed.\u00a0 Also, the round was a very tight fit and had to be pressed into the barrel &#8211; it&#8217;s possible that the bullet became dislodged, seating further down within the case and causing higher pressures when fired.\u00a0 While the barrel was destroyed, we finally achieved primer ignition, so we put Joe&#8217;s barrel back in and continued testing.<\/p>\n<p><a href=\"https:\/\/i0.wp.com\/haveblue.org\/wp-content\/uploads\/2014\/04\/functional-test.jpg\"><img data-recalc-dims=\"1\" loading=\"lazy\" decoding=\"async\" class=\"alignnone size-full wp-image-1762\" title=\"functional test\" src=\"https:\/\/i0.wp.com\/haveblue.org\/wp-content\/uploads\/2014\/04\/functional-test.jpg?resize=614%2C438\" alt=\"\" width=\"614\" height=\"438\" \/><\/a><\/p>\n<p>With things finally working (if not smoothly), we proceeded to fire off as many shots as we could manage during the available sunlight.\u00a0 Here&#8217;s a short video of the successful shots made: <a href=\"http:\/\/haveblue.org\/wp-content\/uploads\/2014\/05\/Sequence-01.mpg\">Lulz Liberator testing video<\/a><\/p>\n<p>The video hints at some of the issues we ran into during testing.\u00a0 We didn&#8217;t have the retainer for the firing pin installed, so the firing pin would rocket out the back during every shot.\u00a0 We used a piece of masking tape on one attempt (you can see it fly up after the shot) to try and keep the firing pin in place, but the hole punched through the tape shows that this did not work at all.\u00a0 We only had one roofing nail, but fortunately Joe happened to have along extra machine screws that he used for assembly and was able to fashion a replacement firing pin each time by cutting and filing it with a pocket multitool.\u00a0 We had to make the firing pin longer each time as well, since each subsequent shot increased the headspace, with the cartridge becoming seated further and further down the barrel each time.<\/p>\n<p><a href=\"https:\/\/i0.wp.com\/haveblue.org\/wp-content\/uploads\/2014\/05\/bent-screw.jpg\"><img data-recalc-dims=\"1\" loading=\"lazy\" decoding=\"async\" class=\"alignnone size-full wp-image-1766\" title=\"bent screw\" src=\"https:\/\/i0.wp.com\/haveblue.org\/wp-content\/uploads\/2014\/05\/bent-screw.jpg?resize=614%2C371\" alt=\"\" width=\"614\" height=\"371\" \/><\/a><\/p>\n<p>The 3 screws holding the breech block in place also became noticeably bent as testing continued, so we replaced them halfway through.<\/p>\n<p><a href=\"https:\/\/i0.wp.com\/haveblue.org\/wp-content\/uploads\/2014\/05\/lulz-barrel-test.jpg\"><img data-recalc-dims=\"1\" loading=\"lazy\" decoding=\"async\" class=\"alignnone size-full wp-image-1768\" title=\"lulz barrel test\" src=\"https:\/\/i0.wp.com\/haveblue.org\/wp-content\/uploads\/2014\/05\/lulz-barrel-test.jpg?resize=614%2C1030\" alt=\"\" width=\"614\" height=\"1030\" \/><\/a><\/p>\n<p>Here&#8217;s what the Lulzbot printed barrel looked like after its first successful firing.\u00a0 The cartridge has actually been pushed back a bit (hence pushing back on the breech block and bending the retaining screws as noted).\u00a0 You can also see white spots forming (known as <a href=\"http:\/\/en.wikipedia.org\/wiki\/Crazing#Rubber_toughening\">crazing<\/a>) as a result of the internal stress.\u00a0 Finally, the primer has been pierced, allowing gas to erupt out the back of the cartridge, which is an undesirable behavior.\u00a0 However, this is not a fault of the Liberator&#8217;s design, but a side effect of using a roofing nail or &#8216;field expedient&#8217; machine screw &#8211; the sharp nose of the nail or screw actually punctures the primer cup, whereas proper firearm firing pins actually have a carefully rounded nose so that they dent but do not pierce the primer.\u00a0 In fairness, however, pierced primers are not a great concern on a disposable firearm such as the Liberator or its WWII ancestor.\u00a0 Continually piercing primers will allow the hot gases to erode the bolt face, firing pin hole, firing pin tip, etc. in a conventional firearm, but for a disposable gun designed to operate only a few times, this is admittedly a minor design quibble.<\/p>\n<p>One thing the photo does not really indicate is how firmly the brass case is actually stuck inside the barrel.\u00a0 In a conventional metal barrel, the brass does expand somewhat during firing, which is actually beneficial in sealing the case to the chamber walls in a process known as <a href=\"http:\/\/en.wikipedia.org\/wiki\/Obturation\">obturation<\/a>.\u00a0 The brass relaxes slightly as the bullet exits the barrel (which allows the internal pressure to drop back down to atmospheric levels), but since ABS plastic is much lower in strength than steel, the brass case expands greatly in the Liberator making conventional extraction all but impossible.\u00a0 In our case, we needed to use a hex wrench and a rock to beat the expended cartridge out of the barrel.<\/p>\n<p><a href=\"https:\/\/i0.wp.com\/haveblue.org\/wp-content\/uploads\/2014\/05\/first-shell.jpg\"><img data-recalc-dims=\"1\" loading=\"lazy\" decoding=\"async\" class=\"alignnone size-full wp-image-1769\" title=\"first shell\" src=\"https:\/\/i0.wp.com\/haveblue.org\/wp-content\/uploads\/2014\/05\/first-shell.jpg?resize=614%2C499\" alt=\"\" width=\"614\" height=\"499\" \/><\/a><\/p>\n<p>Unsurprisingly, the walls had expanded so far that the case had actually split.<\/p>\n<p><a href=\"https:\/\/i0.wp.com\/haveblue.org\/wp-content\/uploads\/2014\/05\/bore-unscathed.jpg\"><img data-recalc-dims=\"1\" loading=\"lazy\" decoding=\"async\" class=\"alignnone size-full wp-image-1770\" title=\"bore unscathed\" src=\"https:\/\/i0.wp.com\/haveblue.org\/wp-content\/uploads\/2014\/05\/bore-unscathed.jpg?resize=614%2C478\" alt=\"\" width=\"614\" height=\"478\" \/><\/a><\/p>\n<p>More surprising to us, though, was the fact that the barrel bore looked entirely unscathed (not only by the projectile, but by the hot propellant gases).\u00a0 The photo really doesn&#8217;t show it, but in looking down the bore, the finish appeared just the same as in the unfired state.\u00a0 Both Joe and I presume that there is so much bore expansion during firing that the bullet itself isn&#8217;t even touching the rifling.\u00a0 Granted, the rifling would have done almost nothing anyhow (a copper jacket is still much harder than ABS plastic).<\/p>\n<p>We only managed to record two shots with the chronograph (we weren&#8217;t using skyscreens, and they probably would have helped).\u00a0 The captured velocities were 498.2 and 465.1 fps, for an average of 481.7 feet per second (146.6 m\/s).\u00a0 By comparison, the very same round fired out of a conventional <a href=\"http:\/\/en.wikipedia.org\/wiki\/.380\">.380<\/a> pistol will be well over 900 fps.\u00a0 Consider that kinetic energy (or &#8216;muzzle energy&#8217; in firearms parlance) increases as the <em>square<\/em> of velocity, and the difference is quite dramatic &#8211; the Liberator only achieves a muzzle energy of 49 foot-pounds, or roughly a quarter that of what a standard .380 pistol provides.\u00a0 By way of comparison, a major league fastball delivers twice as much energy, and one person has actually died as a result of being struck with such a pitch (yet a year later, despite proclamations of mayhem and anarchy in the press, there have been zero deaths or even injuries from 3D printed guns).\u00a0 In the end, then, the Liberator is not at all a weapon of physicality, but a weapon of philosophy, able to challenge preconceived notions regarding governmental control over the sharing of information.\u00a0 Which, whether you agree or disagree with his views and actions, is <em>precisely<\/em> what Cody Wilson set out to accomplish in the first place.<\/p>\n<p>Somewhat unsurprisingly, only a few days after DD posted the .STL files for the Liberator on their site, the US State Department <a href=\"http:\/\/www.forbes.com\/sites\/andygreenberg\/2013\/05\/09\/state-department-demands-takedown-of-3d-printable-gun-for-possible-export-control-violation\/\">sent a letter to Cody<\/a>, demanding takedown of the Liberator files and 9 other designs that had been posted on Defense Distributed.\u00a0 The authority for this stems from ITAR, the <a href=\"http:\/\/en.wikipedia.org\/wiki\/International_Traffic_in_Arms_Regulations\">International Traffic in Arms Regulations<\/a>, which controls import and export of defense related articles, including information related to such items.\u00a0 That acronym may ring familiar to old hands of the internet, as it is the very same statute under which the US government blocked export of Phil Zimmermann&#8217;s <a href=\"http:\/\/en.wikipedia.org\/wiki\/Pretty_Good_Privacy\">PGP<\/a> encryption software in the mid-90s, which saw Phil under criminal investigation for &#8220;munitions export without a license&#8221;.\u00a0 While the case against Phil was eventually dropped (and Cody\/DD have not been actually charged with any wrongdoing), the parallels are striking.\u00a0 Like Phil&#8217;s case, it will undoubtedly be many years before the issue is resolved.<\/p>\n<p>What struck me oddly about the State Dept. letter were the 9 other designs listed as takedown targets.\u00a0 In my opinion, these were picked entirely at random in a perfectly transparent attempt to hide the fact that the Liberator files were in fact the sole items of interest.\u00a0 Specifically, item 6, &#8220;Sound Moderator \u2013 slip on&#8221; was actually designed by noted RepRap contributor (and airgun enthusiast) <a href=\"http:\/\/diamondage.co.nz\/\">Vik Olliver<\/a> and is <a href=\"http:\/\/www.thingiverse.com\/thing:6808\">still available<\/a> on Thingiverse.\u00a0 If this was truly an ITAR violation, then why did the State Department not do anything when Vik originally &#8216;exported&#8217; the file from New Zealand to Thingiverse servers in the US, and why has Thingiverse\/Makerbot\/Stratasys not received their own ITAR takedown letter for continuing to host this design?\u00a0 I could opine a great deal more on the topic, but since I attempt to limit my blog writing to technical matters, I&#8217;ll curtail my musings.<\/p>\n<p>Other interested people have printed their own versions of the Liberator as well &#8211; mashable.com has a superb 8 minute documentary called &#8220;<a href=\"http:\/\/mashable.com\/2013\/06\/02\/3d-printed-gun\/\">I Printed a 3D Gun<\/a>&#8220;, which I highly recommend watching.\u00a0 <a href=\"http:\/\/travislerol.com\/\">Travis Lerol<\/a> (who has also experimented with printing AR lowers on his 3DS Cube) attempts to give his own Liberator a try, but it fails to ignite (spoiler alert).\u00a0 Travis tells me that he has since managed to get a round to fire, though it took about 200 attempts.\u00a0 A number of design remixes of the Liberator concept have also been posted online, though very few (if any) have actually been printed and tested.<\/p>\n<p>I was very honored to be asked by <a href=\"http:\/\/en.wikipedia.org\/wiki\/Hod_Lipson\">Professor Hod Lipson<\/a> to make a presentation at the Chicago <a href=\"http:\/\/www.mediabistro.com\/inside3dprinting\/2013\/07\/\">Inside 3D Printing<\/a> conference on the topic of 3D printed firearms on July 11.\u00a0 I was scared stiff to do any sort of public speaking, but thankfully there weren&#8217;t many people in the audience, and I had a few friends in attendance for moral support.\u00a0 I&#8217;m very glad I attended, as I was able to chat with so many notable people in the field &#8211; not only Hod Lipson, but <a href=\"https:\/\/singularityu.org\/bio\/avi-reichental\/\">Avi Reichental<\/a> (of <a href=\"http:\/\/www.3dsystems.com\/\">3D Systems<\/a>), <a href=\"http:\/\/en.wikipedia.org\/wiki\/S._Scott_Crump\">Scott Crump<\/a> (of <a href=\"http:\/\/www.stratasys.com\/\">Stratasys<\/a>), <a href=\"http:\/\/www.solidconcepts.com\/executive-team\/scott-mcgowan-vice-president-marketing\/\">Scott McGowan<\/a> (of <a href=\"http:\/\/www.solidconcepts.com\/\">Solid Concepts<\/a>) and especially <a href=\"http:\/\/ncdmm.org\/ralph-resnick\/\">Ralph Resnick<\/a> (of <a href=\"http:\/\/americamakes.us\/\">NAMII<\/a>) &#8211; thanks to you all for your time and attention.\u00a0 Chatting with Scott McGowan and some of the other folks from Solid Concepts was especially interesting, given that only a few months later, Solid Concepts would release their own 3D printed gun, the <a href=\"http:\/\/www.solidconcepts.com\/news-releases\/worlds-first-3d-printed-metal-gun-manufactured-solid-concepts\/\">1911 DMLS<\/a>.\u00a0 As a fan of <a href=\"http:\/\/en.wikipedia.org\/wiki\/John_Browning\">John Browning<\/a>&#8216;s entire portfolio of work (and especially the <a href=\"http:\/\/en.wikipedia.org\/wiki\/M1911_pistol\">M1911<\/a> pistol), I was thrilled to see such an iconic, century-old design recreated with cutting-edge technology.\u00a0 Solid Concepts is now actually selling the 1911 DMLS in a limited run of 100.\u00a0 While I wish I could afford one as a collectible (Scott, if you have an extra, please drop me a line!), I&#8217;m simply happy to see the whole 3D printed gun media story finally reach its logical conclusion: 3D printing is simply another manufacturing technology, and its application to firearms is no different than the development of milling machines, investment casting, CNC, polymers, and on and on.<\/p>\n<p>Addendum: I had initially wanted to cover much more of the work done in the past year by others exploring the intersection of gunsmithing and 3D printing, but this post took long enough to write as it was.\u00a0 Fortunately, <a href=\"http:\/\/www.thismachinekillssecrets.com\/author\/\">Andy Greenberg<\/a> (who interviewed Joe and me for several stories last year, and is a superb technology reporter) has an <a href=\"http:\/\/www.wired.com\/2014\/05\/3d-printed-guns\/\">excellent rundown<\/a> of the various designs being experimented with by <a href=\"http:\/\/fosscad.org\">FOSSCAD<\/a>.\t\t<\/p>\n","protected":false},"excerpt":{"rendered":"<p>I realized it has been over a year since I last wrote on the subject (though to be fair, it seems it has been about that much time since I&#8217;ve written much of anything substantial).\u00a0 Since I last addressed the topic in March of 2013, the apex of the &#8220;3D printed gun&#8221; story has been [&hellip;]<\/p>\n","protected":false},"author":1,"featured_media":0,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"nf_dc_page":"","_monsterinsights_skip_tracking":false,"_monsterinsights_sitenote_active":false,"_monsterinsights_sitenote_note":"","_monsterinsights_sitenote_category":0,"_jetpack_memberships_contains_paid_content":false,"footnotes":""},"categories":[2,9],"tags":[],"class_list":["post-1631","post","type-post","status-publish","format-standard","hentry","category-3d-printing","category-gunsmithing"],"jetpack_featured_media_url":"","jetpack_sharing_enabled":true,"_links":{"self":[{"href":"https:\/\/haveblue.org\/index.php?rest_route=\/wp\/v2\/posts\/1631","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/haveblue.org\/index.php?rest_route=\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/haveblue.org\/index.php?rest_route=\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/haveblue.org\/index.php?rest_route=\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/haveblue.org\/index.php?rest_route=%2Fwp%2Fv2%2Fcomments&post=1631"}],"version-history":[{"count":0,"href":"https:\/\/haveblue.org\/index.php?rest_route=\/wp\/v2\/posts\/1631\/revisions"}],"wp:attachment":[{"href":"https:\/\/haveblue.org\/index.php?rest_route=%2Fwp%2Fv2%2Fmedia&parent=1631"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/haveblue.org\/index.php?rest_route=%2Fwp%2Fv2%2Fcategories&post=1631"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/haveblue.org\/index.php?rest_route=%2Fwp%2Fv2%2Ftags&post=1631"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}