Comment by pjbk
1 day ago
People print guns and gun parts. More than you think. Now even more since metal printing is starting to become affordable. I print grip and grip attachments for my 9mms and my AR15, trigger guards, barrel clamps, etc. I also find it stupid since, as the article suggests, what kind of algorithm can you implement to do smart detection of something that could be potentially dangerous? Will it also detect negative space? I print inserts in elastic filament with my gun outlines instead of foam (or as foam templates) for my carrying cases. Will the "algorithm" prevent me to do that too? What about my plastic disc thrower toy gun, or my PKD Blaster prop? Both look like guns to me. What about a dumb AI algorithm that lacks common sense?
Printing barrels and FCUs -- the fire control unit, which is the only thing tracked and serialized in a gun at least in the US -- is more difficult but not impossible. Actually, building a functional FCU that can strike a bullet primer, or a barrel that can be used once is not difficult at all and if you look around you can find videos of people that have tested that with a mixture of 3d printing and rudimentary metal working skills. The major issues on designing those parts are reliability and safety. In the Philippines there is a full bootleg gunsmith industry dedicated to build illegal guns that match commercial ones in those aspects too.
Sadly, instead of having better laws we get fallacy rhetoric by people who probably have never touched, much less fired a gun in their lives.
I don't get it - afaik you can get every single part of a gun except for the lower receiver/pistol frame without any restriction - as those parts are legally defined as the 'gun' - the rest are just replacement parts.
Even for those, you can get 80% finished parts for those - just drill a few holes, and file off some tidbits, and you get an almost factory-spec gun.
I'm no expert on US gun law, but afaik, some states even allow you to make your own guns without registration, as the law defines gun manufacturing as manufacturing with the intent of selling them.
So there's plenty of options, many of them better than making a gun with a printer.
But even all this is typically overkill, I dont think criminals go to these lengths to make their own guns, they just get them from somewhere.
Exactly, but it's less effort to steal a gun or have someone else purchase a gun for you then to 3d print a gun.
But even then it's not that difficult, it's entirely possible and legal in many states to print a polymer lower for a AR15 or Glock 17. Then go buy a parts kit from PSA $450 and have fun zero background check or sales tax required as the smaller gun parts stores do not have multistate business nexuses.
It is also not difficult to 3dprint a glock switch, even though they illegal per the NFA https://3dgo.app/models/makerworld/2035005.
This is 100% virtue-signaling from politicians.
The only usable part a plastic 3D printer will make for you is the receiver, which is the whole point, to circumvent that very narrow legal classification. You're right about alternative lawmaking avenues, but given the 2a pushback on controlling "replacement parts" Americans are kind of stuck with the bed they made.
That was the case like 3 years ago. Things have advanced significantly since then.
> The only usable part a plastic 3D printer will make for you is the receiver
this hasn't been true for like 5 years now
1 reply →
The receiver is like the asset tag on computer servers- it's the one thing that is definitely not replaceable since it has the serial number used for entitlement.
This is my attempt to answer your question about "what kind of algorithm can you implement to detect something dangerous". Disclaimer though, I agree that the proposed regulation is way too broad and will have unintended consequences as written.
If you look at how Apple detects contraband imagery, they hash every image that gets uploaded into the photos app. Those hashes are transmitted to servers that compare them to hashes of known contraband.
A similar system could theoretically be used for STL files. So it isn't about detecting exact shapes, it's about preventing printing of STL files that are already known to be dangerous. This would make it harder to illegally manufacture parts for weapons because it would make it much harder to share designs. If you didn't have the knowledge or skill to design a reliable FCU, you would have to find a design someone with that knowledge and skill created - which the printer could theoretically detect with a cryptographic signature.
As the original author of the post pointed out though, this could and would be bypassed by actual criminals. As with most things like this, it's probably impossible to prevent entirely, only to make it more difficult.
> If you look at how Apple detects contraband imagery, they hash every image that gets uploaded into the photos app. Those hashes are transmitted to servers that compare them to hashes of known contraband.
You're spelling out a specific process in detail--which is the only reason I'm picking on details. Do you have anything documenting what you're describing?
From what I remember, Apple's system was proposed, but never shipped. They proposed hashing your photos locally and comparing them to a local database of known CSAM images. Only when there was was a match, they would transmit the photos for manual confirmation. This describes Apple's proposal [1].
I believe what did ship is an algorithm to detect novel nude imagery and gives some sort of warning for kids sending or receiving that data. None of that involves checks against Apple's server.
I do think other existing photo services will scan only photos you've uploaded to their cloud.
I'm happy to make corrections. To my knowledge, what you're describing hasn't been done so far.
[1] https://www.hackerfactor.com/blog/index.php?/archives/929-On...
Aah okay - I remember it being proposed, but perhaps I wrongly assumed it had shipped. I do wonder sometimes if Apple is doing anything that we aren't privy to with photos that end up in iCloud.
1 reply →
what part of the dangerous part is the actually dangerous part?
its a framing trap to think you have to print or cnc the whole thing in one job.
split it up into many smaller jobs, each one not looking dangerous, rezero start the next section as if its a new job, spiff it all up with a session of crank and curse finishing, and the blockade is meaningless.
FCUs are not tracked in US (aside from full auto trigger groups, which however are classified as "machineguns" in their own right).
Receivers are tracked.
That depends entirely on the gun. Sig "receivers" are just frames and the FCU is the controlled element. At least in the p320.
> people who probably have never touched, much less fired a gun in their lives
People should not have to have great experience with killing machines to be able to regulate them.
In the 1980s, my dad machined a lot of replacement parts for a gunsmith, right here in the UK. All legal, all perfectly legit. I will say it took a hell of a lot more skill than just "download file from thingiverse, press print" - but there's nothing stopping you doing it.
And no-one is (yet) suggesting banning lathes, hacksaws, or files.
The difference is this takes years and years of skill learning and hard graft. Downloading a gun file and pressing print requires nothing.
> Sadly, instead of having better laws we get fallacy rhetoric by people who probably have never touched, much less fired a gun in their lives.
Why is this the litmus test for being qualified to write gun legislation? Do we also expect our lawmakers to have tried heroin or downloaded child porn so that they can regulate those activities?
This is a bad example. I've been notionally pro-ownership but also pro-regulation my whole life, and one of the major problems with gun legislation in the US is that it's incredibly poorly written and does not reflect the technical reality of guns.
The government allows private ownership of automatic weapons, but hasn't issued any new tax stamps for 50 years. You can convert any semiauto gun into a full-auto gun for a few cents of 3D printed parts (or a rubber band). The hysteria over "assault weapons" basically outlawed guns that _looked_ scary, while not meaningfully making anyone safer.
I think yes, it is reasonable for Congresspeople to fire a gun before they legislate on it, because otherwise they are incapable of writing good laws.
Good gun regulation in the US would probably look like car insurance, where gun owners need to register and insure their weapons against the possibility of crimes being committed with them. There are so many guns compared to the amount of gun crime that it would probably not end up terribly expensive, especially if you own a gun safe.
The mistake you're making here is assuming that
> The hysteria over "assault weapons" basically outlawed guns that _looked_ scary, while not meaningfully making anyone safer.
This wasn't the goal by the congresspeople, and that them having fired a gun would've changed that goal.
That was the goal. They knew they weren't going to be able to pass any kind of legislation that actually msde people safer, but they wanted to look like they were "doing something".
This is incredibly common. It's the primary reason behind the TSA and its continuous expansion, for example.
1 reply →
Thats defacto gun registration- and worse: registration with a private entity not beholden to due process. Given current realities, anybody who registers their firearm in such a manner can expect a no-knock raid because they were nearby when somebody phoned in an engine backfire as a gunshot.
4 replies →
You can get a stamp for full auto easily, my neighbor is an FFL and gets them frequently
1 reply →
You're welcome to come up with a better litmus test, but it's beyond clear that lawmakers writing gun control regulation have less than a wikipedia level understanding of the topic. See "shoulder thing that goes up", the weird obsession with the Thompson, the entire concept of an Assault Weapon, etc.
Wikipedia has much better information about guns than most of the people talking about them in politics, generally speaking.
It's not too surprising, considering the way the rules are written at the ATF. There's basically zero logical thought that goes into pistol vs rifle vs felony:
https://www.reddit.com/r/Firearms/comments/a4gnr3/makes_perf...
(Sorry for the reddit link, it's a common image but that was the first url I found from a quick search that had it up front and center).
6 replies →
> Do we also expect our lawmakers to have tried heroin or downloaded child porn so that they can regulate those activities?
It would be nice if they delegated to experts, instead of think tanks or populism, when it came to dealing with these. Both are examples of rampant regulatory failure.
Having first hand experience in contraband, and having the knowledge to create and pass laws are very different things. If you think that current lawmakers dont know enough about contraband to regulate effectively, what makes you think someone who knows loads about drug use and porn would be able to contruct decent watertight legislation?
Knowing the difference between a think tank and experts might be hard without some rudimentary knowledge to spot nonsense? I don't know, actually asking. It seems to me that the primary skill we need in our leaders is that of spotting experts talking within their field and actually listen to them while ignoring others. The primary trait, which is even more important, is character so that they act on what they here in our best interests instead of their own.
At this point, I do expect that of them.
In this specific discussion familiarity does seem relevant. I don't think shooting is so relevant, but printing and assembling are.
You don't have to be a life-long user to regulate heroin, but if you start legislating second-hand heroin smoke, people might look at you sideways. You kinda need to know a little even if you've never actually ever seen heroin. If you demonstrate severe ignorance, people are going to call you on it.
I don't think its unreasonable to ask politicians to be familiar with how the machinery they are regulating functions and is used.
To use your heroin example, this is akin to banning spoons or needles because they heard those are tools of the heroin addict. It shows a lack of understanding on the part of the regulator and has a far reaching effect on people legally using the items.
Having a clue about how guns work, or the general reality of any other field one may be attempting to legislate, is absolutely crucial. With guns it just happens that actually firing them is a good way to gain (some of) that understanding.
litmus test wise, regulators of 3d printing should be able to create strong parts with a variety of 3d printing mechanisms.
they should at least be able to understand that a 3d printer is akin to a turing machine and what the real limits are - strength of the printed material vs length of the strip of memory.
Well didn't they? From the Epstein files, it looks like "all" the elite is involved....
It’s more like people who barely use computers regulating software features and development.. oh wait
I don’t own a gun, and think guns should be regulated more and better, but the heroin let alone another one are just flawed. There are no legitimate, non-life-ruining use cases for either of those analogies.