The results look awfully zippy to me:
Posted on 08/24/2012 8:35:19 AM PDT by marktwain
This is something that would definitely prod me into getting one of these 3-D printers.
Heat it, it will soften and warp. It's not terribly resistant to abrasion. Its tensile strength is nowhere near that of aluminum, much less steel.
A printed plastic AR lower, with judicious use of metal inserts on bearing surfaces, might have a useful service life. An upper would likely fail after a few dozen rounds (if that). A barrel or bolt would be destroyed by the first shot.
I hope somebody is working on a printer that uses metal powder instead of plastic ... print it then sinter it. That process might make truly useful parts for high stress machines like firearms.
Your technical expertise is much appreciated.
This is not about making weapons of war en mass. This is a direct technological assault on the *idea* of gun control. If anyone can print out a cheap .22 that will fire a few shots before self destructing (in a controlled way), and most people acknowledge that fact, then the political control of guns to prevent crime makes no sense, even to the those who never thought about it much.
This is all about information warfare to maintain freedom.
It is much harder to sell gun control as political control than it is as crime control.
And with that in mind, I think that sitting right here at this computer, I could design a completely functional firearm, chambered for a relatively low pressure rimmed pistol cartridge (.22LR, .38SPL, .45 Colt), that could easily be built using a 3D printer and some hardware store material. It would not be a replica of a current design, but based on the strengths and weaknesses of the materials in use. If I had to do so, I would stake my life on such a weapon.
And that, as you say, clearly illuminates the risible idiocy of "gun control".
I used to work for such a company. I don't know about high stress, they mostly do molds and artistic pieces.
exone.com
“I hope somebody is working on a printer that uses metal powder instead of plastic ... “
http://production3dprinters.com/slm/spro250-direct-metal-slm-production-printer
Reminds me of the movie “In the Line of Fire” where the assassin makes a pistol using resin casting. One time use weapon (although two-barreled).
Not as friendly as the plastic printers, yet, but definitely getting there.
I'll have to watch them ... may need to convince my boss we need one.
Hmmmm ... That’s more like it.
This is a direct technological assault on the *idea* of gun control.
As the Liberator pistol of WW2 fame demonstrated, all that one needs is a firearm that can fire reliably ONCE, and that can lead to the acquisition of additional (and far higher quality) firearms and ammunition. Once a single firearm can be printed that can function reliably even once, it is effectively game-over for the idea of gun control.
...and magazine control is utterly dead, since there are several designs out there for plastic magazines for ARs (and if you can do that, you can do it for any magazine).
The highest tech used in making it was an electric drill.
The 3D printers do not change the reality. They change the perception of the reality in a way that large segments of the population can relate to.
Um, you really need to keep an eye on what’s going on.
The technology is already here:
http://www.gpiprototype.com/services/dmls-direct-metal-laser-sintering.html
(I love the corny representation of engineering schedules and pressures - these guys actually “get it” - and while the public will think the whole “pressured engineer” thing is silly, I assure you, in Dilbert-land, this video is a hit).
And then there’s another company:
http://production3dprinters.com/sites/production3dprinters.com/files/downloads/sPro-Family-USEN.pdf
OK, so you don’t like the cost of big industrial lasers. Let’s talk about using 3D printing, glue and casting sand to create molds with 3D printing:
http://www.youtube.com/watch?feature=endscreen&NR=1&v=Z8MaVaqNr3U
I hear people scoffing: “Who builds guns with investment casting? That’s ancient stuff!”
Ruger, that’s who. Go check it out. Ruger’s investment casting business is so successful, they have a whole subsidiary that does nothing but investment casting:
http://www.ruger.com/casting/index.html
An AR lower can be printed out of thermoplastic or polymers and work. The worst physical stress the lower will undergo is monkey-hammering by the operator and holding the buffer behind the recoiling bolt. There’s at least one company I know of selling polymer AR lowers now - not 3D printed, but selling for-real .223 AR lowers.
The issue of the rest of the gun is to print it in metal, and that technology is here, right now, today. People just don’t know about it widely yet. The 3D thermoplastic will be more widely known because it is cheaper - 200W sintering lasers aren’t cheap.
But as with all of this technology, it will only become cheaper over time.
I’d say that DMLS can do that today - out of the materials you describe.
What you want is usually priced higher than your price point - Guild rifles with all that stuff run significantly more than $3.5K. The one outfit I know making a double square bridge Mauser receiver out of titanium is asking more than your price point for the action alone.
Price of printed objects would depend on the number of pieces, just as with all CNC production. Want one piece done on a CNC machine? The price is through the roof compared to a guy spinning handles on a lathe or Bridgeport. Want 100K pieces? Now there’s no contest between the technologies.
And cocking piece peep sights are just nonsense, BTW. Why would I want my rear sight to move? ;-) It looks trick and swank, but there’s little way to get all the slop out of the cocking piece and still have a reliable action. I saw a rifle awhile back with a rear quick-detach scope base that had a rudimentary flip-up peep sight, which I thought was quite functional. Hideously expensive, tho.
Looks like 1/2”...
Actually, I believe you can even sell them, you just can't be in the business of manufacturing them for sale. So ATF's not going to believe you if you say you made 100 last year for your own use, then changed your mind and sold them.
The results look awfully zippy to me:
But a little redundancy is nice. Double-barrelled designs are available, or one can simply build a pair of single shot wapons and carry one in each hand.
I paralleled yur experiments. My ignition system used the percussion firing units from one of the 4-flash *magicube* AG1-b flashcube units used with pocket cameras of the day. That eliminated any metallic content from the battery and wiring and the projectiles were patched glass marbles- tempered, and stout enough to penetrate a 3/4-inch plywood board.
The total cost of the units I built from diethane engineering polymer and PVC tubing was around $4 apiece. At that cost, it wasn't worth my trouble to reload them.
And it would be eliciously ironic if the power of the First Amendment would eventually come to reinforce tht of the second, in a wy that the founders might not have anticipated, but which surely would have delighted them.
Perhaps, like Ben Franklin, I may start calling myself a *Printer.*
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