[DD] 3d printing firearms - Page 6

this will be a gamebreaker during a revolution. that's for sure.

cool.

What is it with the it doesn't matter there are plenty of bad guys with guns anyways?
Maybe where you guys live but believe it or not there are still places on this planet where there arn't many firearms
And i do realise this isn't really possible yet with 3d printing but i'd rather have it not possible at all never.

I find it funny how everyone is getting all excited and talking about the ramifications or printing your own guns. Guns will always flood the black market (no matter how strict the gun control) so if you really want a gun that's where you can get it from. If you're a law abiding citizen free of felonies, there's an easier path to gun ownership (even though being under constant fire).

QFT
Edited by Emmanuel - 9/2/12 at 6:03pm

I would question how a printed gun would hold up under usage, I don't see it surviving the chamber pressures of firearms.

As an example; these are the max pressures as set by SAAMI.

• 9MM has a max pressure of 35,000 PSI for a standard round, and 38,500 PSI for a +P round.
• .357 SIG sits at 40,000 PSI
• .357 Magnum is at 35,000 PSI

the list of course goes on.

My point is, what type of bonding agent is there that could be used in a printing process that would handle these pressures? What type of printer could get the materials packed dense enough to not just fracture? Not to mention these are just pistol pressures, you can easily double the operating pressure when you go into rifles and their various calibers. I just don't see printing a firearm as viable, from a safety aspect that is.
Edited by PostalTwinkie - 9/3/12 at 7:25pm

It may be that they are one off weapons for personal defense? They have three models listed, wiki-weapons A and B, and the AR-15. The AR-15 info seems to be only for printing the regulated part and you buy all of the other parts yourself. I don't know if this makes it more viable for repeated use but it may. There's hardly any info on the other 2 weapons though.

I don't see a plastic or synthetic barrel being able to stand up to those kinds of pressures and temperatures. Even if you could get the barrel to withstand the pressure of a gunshot I think the immense heat and friction of a bullet passing down a plastic barrel would quickly ruin the inside surface of the barrel. If you have ever tried to put a unfired bullet into the muzzle of a gun you will know it is an extremely tight fit. I don't see any way that plastic can stand up to that kind of abuse. Especially printable plastic.

I think 3D printers are more for printing up quick prototypes and seeing examples of products in 3d. Not building functional firearms. There is a reason that the best guns that cost many thousands of dollars still have steel barrels.

And a single shot gun is useless for self defense. Besides, small caliber single shot pistols are so cheap anybody can afford them...

Maybe some day in the future when they can print metal. But even then the metal would not be properly tempered or forged. Printing a receiver is an interesting idea. But I'm not sure I want a plastic framed gun. I also think that the tolerances of 3d printing, especially home made repraps. I was at the wiki for that site and they were saying that about 0.3mm tolerances are to be expected. That is absolutely unacceptable for gun tolerances. The cheapest guns are better than that.
Edited by Epitope - 10/4/12 at 12:45am

The technology for metal 3d printing has been out for years.

http://3dprinting.com/materials/metal/3d-printing-metal/

Finally, someone with a basic understanding of the problem. There isn't a material that is used in a 3D printer that can handle the pressures involved, even the printed metal which must then be heated in a very hot oven. Fact is, try to print out an entire gun(minus springs, those MUST be obtained elsewhere)load it, and what you have just done is to create a grenade. One that will maim or kill the operator.

.308 Win ~ 62,000 PSI

A 3D printer is simply the wrong tool for the job. There IS a right tool(s), and that would be a small mill and standard bench lathe combo. The small Chinese made X2/X3 minimills can be converted to CNC and have the capacity to mill full size pistol frames and AR receivers. Or if American made is a concern there's a small company called Tormach that is a touch more expensive, but I would argue worth it for a leap in quality. As for a lathe I recomend a Grizzly Gunsmithing lathe because ti's the onyl affordable one that I know of. Grizzly also has books on the subject as well as on learning CNC programming, and all of the tooling that you will need to purchase like bits, rotary tables, etc..

www_cncguns_com has free to download files for just this purpose and the forums are a wealth of info. Also check out homegunsmith.com and the Sniper's Hide gunsmithing forum.

There are legal issues involved but it turns out that there's a very large loophole in US gun control laws when you make your own firearms/silencers with no intent to sell. Commerce clause can only apply when commerce is actually taking place, after all, and all federal gun control laws had to be based around collecting a tax for people to even pretend that those laws are constitutional. It turns out that what you are not allowed to buy without an FFL, you usually have no problem fabricating legally. Check state and local laws of course.

Oh, and yes it's a SILENCER. At least that's what Maxim called them when he invented the dang things. Or to be honest I prefer the term "muffler" since it's the exact same technology used to muffle the exhaust from an engine.
Edited by Jarhead - 10/6/12 at 5:51am

Printed firearms are still viable even if you need to add an easily obtainable and virtually free metal tube from somewhere else. I can fire .22 hornets (upwards of 40k psi) all day from a metal pipe that used to be part of a coffee percolator. And before any comments on accuracy, rifling doesn't really matter much at the ranges of most self defense or criminal use, which is quite literally spitting distance.

Also, plenty of plastics will easily handle common pistol round chamber pressures safely, at the cost of being inaccurate and disposable. The weapon in question is going to be based around the .22LR. With such a small round and such modest pressures, it's not going to be hard to make a compact weapon that can safely fire it, even if the receiver and barrel are 100% ABS plastic.