| by Stian Lothe

This piece was sponsored in thanks to the Kathryn Wasserman Davis Collaborative in Conflict Transformation grant.

Introduction

In 2013, President Barack Obama praised 3D printing as a transformative technology, pointing to how an innovation lab in Youngstown, Ohio, had successfully mastered the technology for industrial use. “There’s no reason this can’t happen in other towns,” he predicted. A decade later, in New York City, the most widely publicized murder of 2024—the killing of UnitedHealthcare CEO Brian Thompson—was allegedly committed with a 3D-printed gun equipped with a 3D-printed silencer.

Though garnering far less media attention, 3D printing had been mastered in yet another town in 2024. In Santa Rosa, California, a 14-year-old high school student produced semi-automatic firearms from his private bedroom. On February 14, 2024, the teen was arrested at Montgomery High School after Santa Rosa police executed a search warrant at the student’s home earlier that day. During the search, police discovered a 3D printer, the frame of an unfinished semi-automatic pistol, and ammunition. This case highlights the potent intersection of two pivotal developments: the introduction of affordable consumer 3D printers and the release of first downloadable firearm blueprints. Together, these advancements have made firearm manufacturing accessible to minors, underscoring the unintended risks of a rapidly evolving technology. Contrary to the President’s early optimism, the Santa Rosa case illustrates the urgent need to assess and address the growing threats associated with 3D printing.

While no school shootings involving 3D-printed firearms have occurred to date, incidents like Santa Rosa reflect a troubling trend. In Davidson County, North Carolina, a teenager recently brought a non-functioning 3D-printed gun to his middle school, and in Houston, Texas, a student threatened to commit suicide with a self-made firearm. When including ghost guns—firearms assembled from online-purchased kits—incidents of school violence involving untraceable weapons are increasing, with some resulting in serious injuries from their discharge.

Each time a minor successfully manufactures a firearm, the risk of the first school shooting involving a 3D-printed weapon grows. This raises three urgent questions: How do the affordability, accessibility, and sophistication of 3D printers and weapon blueprints enable minors to create firearms? What steps are required to produce a 3D-printed weapon, and what loopholes allow minors to bypass existing regulations?

This article addresses these questions by first examining the evolution of 3D printers and printable weapon designs. It proceeds by detailing and retracing the likely steps taken by the Santa Rosa teenager, revealing the challenges and opportunities that allow American minors to create firearms through 3D printing in 2024. By examining the widespread accessibility of 3D-printing technology, this article seeks to ignite critical discussions on school safety and the risks posed by 3D-printed firearms. It also highlights significant policy gaps that require urgent research and action to prevent the devastating possibility of the first school shooting involving a 3D-printed gun.

The 3D Printer: 40 Years in the Making, 10 in the Hands of Consumers

1980s – 2010s: A Revolutionary Technology Reserved for Industrial Use

While many may perceive 3D printers to be a hallmark gadget of the 21st century, its technological roots actually trace back over four decades, with the first patent applications filed in 1980. Just seven years later, the first commercially available 3D printing system, known as the SLA-1, was introduced. This pioneering technology was predominantly accessible to industrial users due to its high cost (approximately $300,000 USD) and complexity of use. Now an artifact at the National Inventors Hall of Fame Museum, the SLA-1 was a groundbreaking product used to create prototypes for industrial products and detailed medical models for surgical planning, among other applications.

2010s – 2020s: The 3D Printer Enters American Households

The following decades were marked by significant technological advancements in efficiency, user-friendliness, and cost reduction. However, it was not until a 2014 Kickstarter project that a 3D printer considered truly accessible to consumers emerged. The resulting M3D Micro Printer became the first of its kind to overcome four major barriers that had hindered earlier attempts to make 3D printers available on a consumer level: price, user-friendliness, machine quality, and ease of maintenance. While one tech review noted the printer’s “inconsistency” in both output and performance, the author emphasized its affordable price ($349 USD), describing the M3D Micro as “geared to newbies making their first foray into the 3D printing world.” To illustrate how profoundly the 2014 Kickstarter project changed the affordability of 3D printers, one only needs to recall that 2007 marked a “milestone year,” with the release of the first 3D printing system priced under $10,000 USD.

2024 and Beyond: Enhanced User-Friendliness, Affordability and Quality in a Growing Billion-Dollar Market

Today, the average entry-level 3D printer costs $200 - $300 USD and offers significantly higher build and print quality compared to those from the early 2010s. Furthermore, just over the past three to four years, several new features significantly enhancing user-friendliness have become standard on entry-level printers. Previously, 3D printers often had cumbersome liquid crystal displays that were challenging for beginners to navigate. In 2024, vibrant touch screens, which even allow users to preview the model they are about to build, are now standard. Additional recent features that have made 3D printing easier include automated bed leveling for higher print quality, flex plates for simplified print removal and enhanced bed adhesion, and increasingly user-friendly software with presets and guides that help beginners prepare print files without needing advanced knowledge. It is also worth noting that the general interest in 3D printing exploded during the COVID-19 pandemic, with an estimated 870,000 3D printers operating in American homes just two months into the outbreak.

The battle for dominance in the consumer-grade 3D printer market is fierce, with over a dozen companies competing to offer the best printers. In the current top five of Amazon’s best sellers in 3D printers, one can find models made by Flashforge, Creality, Elegoo, and Entina, with prices ranging from $162 to $379 USD. The most common type of filament used in 3D printers is Acrylonitrile butadiene styrene (ABS), which is the same material used to make Legos. The number of players in the 3D printing business today is undoubtedly due to the exponential growth of the global market over the past decade, a trend projected to continue. The global market size, which was $4 billion USD in 2013, had expanded to no less than $20.68 billion USD by 2023.

Over the next decade, with entry-level 3D printers already proven to produce high-quality prints in 2024, it is likely that the companies that make them will increase their focus on reducing production costs while introducing more user-friendly solutions and features. This combination could lower existing barriers for consumers to adopt 3D printing technology in a market expected to reach the size of $117.78 billion USD by 2033.

3D-Printed Weapons: From Disposable “Liberator” to Semi-Automatic “FGC-9” and the Growing Open-Source Communities

The Liberator: Starting Shot for a New Era in Ghost Guns

On May 6, 2013, Defense Distributed, an open-source company providing firearm designs in the form of CAD (computer-aided design) files, released the blueprints for a 3D-printable pistol named the “Liberator” on their website. Despite its relatively rudimentary design and limited lifetime, the Liberator is known for being the first widely accessible, fully functional 3D-printed pistol. The pistol is made from 15 printable parts made of ABS. A one-kilogram spool of ABS costs about $20 USD, and is more than enough to make print the parts of a Liberator. The whole pistol can be assembled by adding only a single metal nail for the ring pin. When printed and assembled correctly, the Liberator is expected to endure 8-10 shots before needing to be discarded.

Ghost Gun
A fully assembled 3D-printed Liberator pistol. (Photo: Unknown)

3D-Printed Guns in 2024: Semi-Automatic “FGC-9”, Bump Stocks & Fully Automatic Machine Guns

Over the decade following the introduction of the Liberator, 3D-printed guns have undergone significant advancements, primarily characterized by improvements in technical features, material quality, and accessibility. From rudimentary and unreliable designs that could pose high risk to the user, the downloadable weapons of the 2020s are marked by complex and robust designs, utilizing a combination of high-strength polymers and metal components produced by more advanced 3D printers. This evolution has led to firearms that are not only more reliable and durable, but also easier to produce, with detailed instructions and pre-assembled components available for download. Additionally, the increased accessibility of sophisticated 3D-printing technology and the proliferation of online sharing platforms have made it easier for individuals to both access and distribute these designs.

A fully assembled 3D-printed FGC-9 semi-automatic 9mm firearm. (Photo: Unknown)
A fully assembled 3D-printed FGC-9 semi-automatic 9mm firearm. (Photo: Unknown)

One of the 3D-printed firearms that exemplifies the above advancements, and remains readily available to download, is the “FGC-9” (an abbreviation for “Fuck Gun Control 9mm”). The FGC-9 is a fully functional, semi-automatic 9mm pistol-caliber carbine that incorporates metal components and high-strength polymers, enhancing its durability and reliability. The FGC-9 is designed to be assembled with commonly available materials and parts that can be printed or sourced locally, making it accessible to a broader audience. Its sophisticated design includes a rifled barrel produced through electrochemical machining, which significantly improves accuracy and performance compared to earlier 3D-printed guns. In addition to semi-automatic guns like the FGC-9, bump stocks turning licensed semi-automatic guns automatic, and even fully automatic 3D-printed machine guns are among the designs fully developed and operational in 2024.

The Rise of 3D-Printed Firearm Open-Source Communities

The rapid evolution of these designs has not occurred in a vacuum; it has been driven by 3D-printed firearm communities and influential individuals. A key actor in this community is Cody Wilson, an American gun rights activist and co-founder of Defense Distributed. The company initially launched with a “Wiki Weapon Project” fundraiser, seeking donations by promoting the idea that “defense systems and opposition to tyranny may be but a click away.” Defense Distributed is also the parent company behind DEFCAD, the largest search engine and repository of 3D-printed gun files in 2024.

As a result of the legal turmoil that has followed Defense Distributed and DEFCAD since 2013, a decentralized community known as FOSSCAD (an abbreviation for Free Open Source Software & Computer Aided Design) quickly emerged. The movement leverages advancements in 3D printing technology and CAD software to create digital files that can be freely shared and used by individuals to manufacture their own weapons and accessories. Eventually, FOSSCAD transitioned to a more scene-based model, but continues to maintain an open membership on IRC (Internet Relay Chat) and hosts an extensive GitHub archive of various files released over its history.

Today, 3D-printed firearm enthusiasts connect through various platforms such as Subreddits, like r/FOSSCAD with over 104,000 members, and Discord channels. Additionally, members of the community meet in physical arenas. The National Gun Maker’s Match, featuring “3D Printed […] competitions for Rifle, PCC and Pistol,” is an annual event where ghost gun producers meet up to showcase their latest innovations in 3D-printed firearms.

Legal Battles and the 2024 Federal Task Force

Only two days after the Liberator was published in 2013, the U.S. Department of State demanded Defense Distributed to unpublish the patterns, initiating a series of complex legal battles. Initially, the government prevailed in these court cases, successfully blocking the publication of 3D-printed gun files on national security grounds. However, a 2018 settlement and subsequent legal challenges gradually shifted the landscape, with a federal ruling in 2021 ultimately allowing for posting plans for 3D-printed firearms with a license issued by the Bureau of Industry and Security. While most laws concerning the manufacturing, sale, and possession of guns also apply to those that are 3D-printed, these legal proceedings highlight an ongoing tension between technological innovation, free speech, and regulatory control.

In September, 2024, in response to the growing threat of untraceable firearms, President Biden signed the Executive Order on Combating Emerging Firearms Threats and Improving School-Based Active-Shooter Drills. The order included establishing a federal task force that will address the proliferation of 3D-printed guns and enhance oversight. The report, due on December 25, will include a risk assessment and strategy covering topics such as the origins and distribution of 3D-printed firearms, the feasibility of restricting software that enables the production of undetectable guns, and improved law enforcement coordination to identify and report these weapons.

While the order includes measures to enhance school safety, such as improving active-shooter drills and training law enforcement to identify undetectable firearms,  it does not mandate action to restrict minors’ access to 3D-printing technology or the firearms they can produce.

The Santa Rosa Case: Tracing the Five Steps Allowing Minors to Manufacture Semi-Automatic Weapons

Following the arrest of the teenager on February 14, 2024, Santa Rosa police released a photo of the items they obtained from the search of his family’s home. The photo (shown below) shows a printer  known as the Creality Ender-3 V2 towards the top of the image. Below, towards the bottom, the printed frame of an unfinished Glock 19 9mm semi-automatic pistol is visible. Together, the printer and the gun reveal the probable steps taken by the teenager to reach this stage of production. Furthermore, by retracing these steps, the existing loopholes that allowed the teenager to progress this far become evident.

 A Creality Ender-3 V2 3D Printer found in the home of the Santa Rosa teenager together with the printed frame of an unfinished Glock 19, ammunition and other items obtained during the execution of the search warrant. Photo: Santa Rosa Police Department
 A Creality Ender-3 V2 3D Printer found in the home of the Santa Rosa teenager together with the printed frame of an unfinished Glock 19, ammunition and other items obtained during the execution of the search warrant. Photo: Santa Rosa Police Department

Step 1: Purchasing the 3D Printer

It is plausible that the teenager’s first step was to purchase the 3D printer. The Creality Ender-3 V2, first released in 2020, currently retails for just under $200 USD, with used models available for under $100 USD. In addition to their capability of producing deadly firearms, 3D printers can also pose significant safety risks. These include serious burns from heating elements and electrical faults, and health hazards such as lung injury from fumes released by melted plastics. Moreover, UV lights used in some 3D printers can cause eye damage. 

Despite these safety risks, there are currently no laws in the United States regulating age restrictions or requiring parental control for purchasing and using 3D printers. This lack of regulation also applies to printer filaments. Additionally, there are no laws requiring 3D printer manufacturers to restrict or control the types of designs their machines can produce, including weapon designs.

Step 2: Looking Up 3D-Printable Weapon Designs

Assuming that the teenager already knew what kind of gun he wanted to produce, the likely next step would be to retrieve the CAD files for a printable Glock 19 pistol. A quick Google search yields several websites that offer these files for free upon visiting the site. If the Santa Rosa student was uncertain about where to begin or which gun to download, reframing the Google search to a question could quickly direct him to Reddit threads where similar questions have been posed, as well as YouTube tutorials offering guidance on 3D-printing firearms.

Despite U.S. lawmakers urging action in a 2018 letter, Google still lacks filters against open-source websites offering free weapon designs and the online communities that facilitate access to them. Additionally, the most prominent 3D gun community on Reddit, r/FOSSCAD, does not have any age restrictions. Few, if any, of the YouTube videos promoting various types of 3D-printed guns and their ease of production appear to have age restrictions.

Step 3: Downloading the Gun Files

Leaving the search engine, none of the websites providing downloadable weapon designs appear to have any immediate age checkers when entering the site. Often topping the search results, DEFCAD, the largest repository of 3D-printed gun files in 2024, requires visitors to create an account in order to download any of their gun designs. When registering a new account, however, a new user only needs to provide an email address and create a username and password. Only under the terms of service, which is located on a separate page, is it mentioned that “you must be at least 21 years old.” However, new users do not need to enter their current age or verify it, and can easily browse available weapon designs that can easily be purchased by using fake ID. Regardless, many of the designs DEFCAD offers are widely circulated on the web for free.

An example of such a site, also highly ranked on Google, is Odysee. A decentralized video-sharing platform on the blockchain-based file-sharing network LBRY, Odysee offers a myriad of video tutorials and easily accessible designs, ranging from the Liberator to the latest version of the FGC-9. Unlike DEFCAD, Odysee does not require users to create an account or provide any personal information to access its content. There are no age verification measures in place, which allows visitors of any age to freely view and download these files.

With the exception of the State of New Jersey blocking access to DEFCAD, platforms like Odysee—where users can access and download printable gun designs for free without any restrictions—remain readily available to residents across New Jersey and the rest of the United States.

Step 4: Ordering Non-Printable Gun Components

Most 3D-printed firearms require specific metal parts to ensure longevity and safety. These parts are typically listed in a text document accompanying the firearm’s STL files. For example, when downloading an open-source Glock 19 design online, the associated text document categorizes the “off-the-shelf Glock parts” into upper and lower part kits and provides information on specific U.S. vendors offering these parts.

Notably, many websites supplying metal components such as barrels and sliders do not have an age verification process. Ordering these parts generally requires only access to a credit card. Full kits to complement a self-printed pistol frame range from just over $100 to $500 USD, depending on the design and the number of parts needed.

Step 5: Printing and Assembling the Weapon

Based on the photo released by the police, the Santa Rosa high school student had finished printing and started filing the frame of the pistol. Although 3D printers have become faster, printing the necessary parts to make a pistol can still take 15-20 hours. Assembling the remaining parts is also time-consuming, often taking several hours. Despite advancements in technology, 3D-printed firearms still tend to jam, as evident in the surveillance footage of Luigi Mangione shooting Brian Thompson, where his 3D-printed ghost gun malfunctioned mid-attack. Makers may need to refine or adjust the printed parts further to ensure precise fits, reducing the risk of jamming and improving the firearm’s functionality.

Limited Cost and Skill Required for Minors to Produce 3D-Printed Firearms

In summary, producing a 3D-printed firearm like the Glock 19 has become alarmingly accessible, even to minors, due to the relatively modest financial investment and basic skills required. Acquiring a 3D printer and the necessary filament materials can cost under $200 USD, while additional metal parts and kits range between $100 to $500 USD. The process involves straightforward steps: purchasing equipment, sourcing design files, downloading and printing parts, and assembling the firearm. These tasks demand minimal technical expertise, and numerous online resources provide detailed guides and support. Despite some challenges in ensuring functionality, the barriers to creating a functional 3D-printed gun are low, making this technology easily exploitable by individuals with limited experience and financial resources.

Conclusion

The rapid evolution of 3D printers and printable ghost gun designs over the past decade is deeply concerning. Once a technology celebrated for its potential to revolutionize manufacturing, 3D printing has also become a gateway to producing sophisticated, unserialized semi-automatic weapons. Now affordable and advanced, 3D printers have transitioned from industrial tools to household items, while firearm designs have evolved from rudimentary pistols to complex rifles readily downloadable from the internet. The convergence of these developments underscores the urgent need to address the risks posed by this technology.

The Santa Rosa case provides critical insights into the steps and loopholes that allow minors to create 3D-printed guns, offering a foundation for solutions. To address current vulnerabilities, future research should explore implementing mandatory age verification for purchasing 3D printers, accessing firearm blueprints, and ordering non-printable gun components. Additionally, restricting search engine access to websites hosting weapon designs could significantly mitigate risks. While each measure raises barriers individually, together they hold the potential to prevent the first school shooting involving a 3D-printed gun from ever occurring.

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