Skip to comments.Surprising Tools of Modern Gunmaking: Plastic and a 3-D Printer (NYT)
Posted on 01/29/2013 5:01:19 PM PST by Brad from Tennessee
A man in Wisconsin viewed it as a technical challenge. Another, in New Hampshire, was looking to save some money. And in Texas, a third wanted to make a political point.
The three may have had different motivations but their results were the same: each built a working gun that included a part made in plastic with a 3-D printer.
What they did was legal and, except for the technology and material used, not much different from what do-it-yourself gunsmiths have been doing for decades. But in the wake of the shootings in Newtown, Conn., and the intensified debate over gun control, their efforts, which began last summer, have stoked concerns that the inexpensive and increasingly popular printers and other digital fabrication tools might make access to weapons even easier. . .
(Excerpt) Read more at nytimes.com ...
Sounds fun but in California it would be classified as a “zip gun” which is illegal (who would have thought?). The plastic AR-15 lower would work the best as it doesn’t have to deal with any stress (that’s all in the upper receiver which isn’t considered a gun by the ATF, only the lower). Still wouldn’t stand up to too much use but would do in a pinch.
The reality is that neither will do you much good if you can’t get bullets and you can’t practice with it. If guns are made illegal what are you going to do? Most likely hide them or bury them. Ask the Scott’s how much good that does (they still find claymore’s in roof thatching every once in a while by the way).
Without some kind of organized resistance there is no resistance and just like in the old CCCP the police (and their informants) are everywhere. This is why modern police states typically do not fall until they have economically collapsed, because as long as they have money to pay for the thugs (police in this case) to keep on beating down the population the lid will stay on the pressure cooker. As went the Soviet Union so will go the USSA, but what comes after may not be any better and could be a lot worse than what comes before.
This printing a gun crap is just ridiculous. Printing the plastic parts is not printing the gun. You could whittle the plastic bits from wood - who cares. Try printing the 4140 steel parts, you useless geeks. Have we reached a univeral retardedness or what?
the plastic lower receiver does not have
look exactly like its metal counterpart.
is there some reason that the part can’t be beefed up
where needed, to make it usable?
Print me a lead bullet and some gunpowder you complete fools. I’m done with this geewhiz print a gun crap.
What is the best way to invest in 3-D gun printing, to keep the technology going?
I agree that the plastic printing stuff is limited in practicality (though it is perfect for testing new parts for fit before using the same data files to run the CNC machine tools). I do like the fact that these 3-D image files are flying around the internet. It helps the goal of the left - full disarmament of the people - slip further from their grasp.
zagger, you seem to be missing the point.
all the parts of a ar-15, can be ordered mail order,
without needing a FFL,
except the lower receiver.
Plastic 3D printed lower with metal parts for completion works well with a 22 cal AR-15 upper. When 3D printers that uses less brittle and bit more rubbery plastics are available for home use, printed AR-15 lowers would be more resilient to handle 5.56mm or .223 cal. Right now one can with a CAD program thicken the stress points of the original AR-15 lower without interfering with the moving parts and upper functions is possible to make the design more resilient with ABS. Problem with plastic is the heat generated from excessive and sustain firing can melt the lower plastic receiver. I do not know how well these ABS plastics can survive cold storage without it shattering under stress. Metal sinter 3D printers are available but very expensive to own privately. IMHO 22 cal AR-15 is possible with a 3 D printed lower. Anything heavier would have problems.
I designed some involute spur gears a few years ago on a 3D CAD system and had some SLS rapid prototypes made. We used SLA (stereolithography) back in the 90s, but it was kind of brittle.
The SLS gears ran fine, but they were not near strong enough to transmit any real torque.
Until these 3D printers use engineered firearm polymers, the idea of making firearms this way is absurd. Then, there is the steel component issue you brought up. That makes the idea of 3D printing a gun with current technology practically useless.
The original gears I redesigned were ABS. It’s not very strong, and UV light severely weakens it’s mechanical properties.
The production gears we used were made from PBT, which is about 4X stronger than ABS.
What if the ABS part was painted with Durocoat, would that block out the UV affects?
“What if the ABS part was painted with Durocoat, would that block out the UV affects?”
It probably would. There are UV stabilizers that can be added to plastic compounds.
I just think there are better plastics than ABS, and firearms’ plastics are specially engineered, not generic general purpose plastics like ABS and acetal copolymer.
Print me a sausage & pepperoni pizza with everything on it!!
You are absolutely right. Something I've been saying is that the politicians are going after stupid 3D printers, that are going to put maybe 20 plastic toy guns out there to be played with by hobbyists. Meanwhile, gangs and punks are getting real guns easily and don't obey any laws. Politicians are hurting the rights of honest citizens and ignoring the punks and their crimes. This news about plastic printers is a waste of time.
How about printing suppressors?
I seriously doubt that would work. Suppressors need to be metal to handle the heat and pressure.
Original stereolithography prototypes were made for “show and tell” marketing demonstrations. My company made some SLA rotors for a flowmeter that we actually tested, but they did not have the long term wear properties for production use.
3D printers can make functional parts now. However, I do not think they can currently make parts strong enough to make something like an engine or a firearm that would be durable enough to have an acceptable lifespan.
They do have metal sintering 3D printers now, and some engines use sintered, or “powdered metal” connecting rods.
A 3D printer can make a part like that, but I’m honestly not sure if it would have the mechanical properties to be strong enough to work.
Perhaps a freeper out there could enlighten us?
Perhaps you could answer some basic questions for me.
I get the concept of directing the laser in three dimensions, but after the ‘soup’ is mixed how does the process proceed.
What holds the first transformed molecule in a fixed position within the ‘soup’, allowing precise and accurate continued ‘building’? Assuming that heat is generated at the point of creating the solid are aspects of fluid dynamics at play at that scale? Is there an armature of sorts that’s seeded?
Is it possible that a carbon fiber wire frame form can be used as an armature upon which layers are added all around, thus providing reinforcing.
Interesting that you closed with “...would be durable enough to have an acceptable lifespan.”. Might well be that acceptable life span could be altered by having the means for production at hand. Barring catastrophic destruction one might accept a shorter product life span knowing that you’ve already got another one in the oven.
And there are scenarios where early catastrophic failure is a positive feature much in the way battlefield weapons are left booby trapped.
I have read that the points are measured in microns so the lasers and the plastic dispenser meet at a very finite point. The 3D is plotted in the x,y and then repeated in the z until each layer is complete.
Theoretically you could lay in some kind of nano-fiber to strengthen the layers similar to the way fiberglass can strengthen cement.
I think the end result will be some form of the above in conjunction with a radical redesign of the firing mechanism.
I think because because early designers were working in steel, the designs didn’t give much attention to the forces created by the bullet.
I think that there are possible designs that could severely limit the impact of the bullet recoil on the frame of the gun resulting in a metal barrel / coil / piston / plastic frame hybrid that would stand up to repeat firing... not going to work using current gun designs though....IMHO
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