I build a lot of rapid prototypes (3d models). It will work, but like others have said, it is a question of when will it fail, not if it will fail.

If you have access to a machine shop you could make the tight tolerenced areas to maximum material spec. Then give those areas a once over with a mill.

Thanks man, make a new thread when it comes time to test it.

This pleases me.

 

Hay guys I totally didn't read the thread but has anyone suggested sleeving the holes yet?

I haven't posted this yet in this thread, but as a citizen of a ban state, this possibility makes me very happy


http://www.thingiverse.com/thing:11636

ETA:

and
http://www.thingiverse.com/thing:11669

Yes.  I'm going to try running without sleeves to begin with.

you're going to break off the receiver extension in a heart beat.

There is NO indication that simply printing or machining your own AR-15 at home violates any laws at all.

Frankly, it is frightening how many people on this and other gun-specific sites are ignorant of the legality of home-building of assault rifles, pistols, etc.

A good comparison would be members of a "beer appreciation forum" who ignorantly believe that home-brewing of beer is illegal.

The fact is: most adult citizens who can lawfully own a typical gun can also "make" such a gun at home IF it is for their own personal use.

In the U.S.A., we do NOT register guns (although some states do have such infringing laws on their books). Unless state law requires it, a home built gun does NOT require any serial number on it at all - although it is recommended and I personally think it would be very foolish not to put some sort of made-up, fictitious number on such a gun.

Like the beer analogy above, the gun must be made WITH THE INTENT to use it yourself, so you could not (for example) start selling your home-made beer or a home made gun out of the trunk of your car for profit.

Also, you have to do the work YOURSELF. I can't ask the local brewery to take my beer kit, make beer for me & then I simply claim "look what I made!" (I did not make anything in such a case) - same goes for guns. A gunsmith CANNOT make the gun for you!! A special FFL holder who is licensed to "manufacture" guns could take on such a project - though in that case a serial number IS required, along with NICS check, taxes, etc. as you are simply purchasing a firearm that was lawfully manufactured.

At any rate, please understand that: under certain circumstances, a person can make guns at home in the U.S. (for now).  That includes printing them out, as long as you own the printer to do it and you have the intent to keep what you make.

So if you loan me a tap or a drill bit to finish my 80% aluminum lower, that means I didn't actually do the work myself?

I'll say two things:

1) Don't believe people who tell you that your ideas won't work. Nearly EVERY SINGLE thing that I've done that's been innovative I've been met with by people with opinions telling me that it won't work. XYZ will fail, et cetera.

2) Don't test it by shooting it yourself. Set up a fixture and engage it from a safe distance. Take it apart and find the weaknesses. You may only get one failure to mess yourself or someone else up permanently. I would look into trying different sizes designed to fail (for instance, thinner sidewalls and buffer tube to find out where the stress is) and then add reinforcement to those areas. I would be most concerned over having extra strength at the takedown pins and buffer tube. A failure that screwed up would allow the angle of the buffer tube to change while firing would be bad.

Does anyone know how much force is exerted against the bolt when the gun fires? If the bolt were to shoot into you from blowback pressure, how extensive would you expect the injuries to be?

I'd also be curious how it handled the heat of continuous firing.

Funny you say this as i was just thinking about this the other day
about how many people talk an inventor out of inventions.

Saying they will never work etc, too many followers and not enough leaders.

No. AFAIK, BATF has never stated that the maker must own the tools used to make the firearm.

In your example, then no.  In fact, some people apparently do a "group buy" on a tool such as a jig & lend it back & forth (using it themselves to do the work).


The problem with not actually owning the tooling come in when someone inevitably takes the logic to the Nth degree, disregards the requirement to DO THE WORK PERSONALLY and tries to get a gunsmith or machine-shop to actually perform the work.  THAT SCENARIO WILL NOT FLY.  

So how WILL someone take that logic too far with 3D printers?

Some fool will buy a 3D printer, start making lowers and set EVERYTHING UP to print one.  Then, he'll go on the internet & invite others to make lowers on his 3D printer. The "invitee" would concievably show up, push "enter" and then try to claim that he "did the work" to make the lower (buy pushing one buton).  Internet pics follow.

PRESTO! .gov gets involved and ruins things for EVERYONE.  

Think it can't happen?  Ask about the 7.62x39mm handgun fiasco.

Are you starting to see WHY I couch things in the most cautious language possible & try to AVOID any possible grey areas?  If you want to print lowers, here is my advice: BUY THE DAMN PRINTER & DO IT YOURSELF.  You can sell it later.

Technically, 3 stepper (or servo) motors did all the "work".  Neither the person who set it up or the person who pressed 'enter' on the keyboard did it.  Unless you want to get ridiculous and count the infinitesimal amount of work done by pressing keystrokes.  

But by that logic, we might as well say the UPS driver who delivered the printer worked on it, too.  Did far more, actually.  Probably expended an order of calories more moving the box from his truck to your garage.

Besides... there isn't really much setup work on a cnc 3d printer.  It's not like a CNC mill where you have to align your part to the work surface and the spindle and zero everything out in the controller program.  And then align it to known reference points for multiple operations.

It prints goop out in a single "setup."  There's no stock to align.

Once again, the law is retarded.  Reality and human ingenuity can't help but make a constant fool of it and the people who wrote it.

Everybody saying as long as you "press the go button" or are there in person "you" built it, that's fine but I'd be real careful.  



I can't remember the name of the company, they were marginally well known.  Hopefully someone here will remember the details of the case it's been a few years back.  Anyway the way it worked was you bought 80% lowers from this company, and then went there for "build parties."  You would use all their programmed CNC shit to complete your piece into a functioning lower.



The ATF took a dim view of this and caused much grief for all involved.  

I remember that guy.  IIRC, he also had alot of middle fingers to the ATF and the Feds in general on his website.

That's KT Ordinance and they are still in business.

How well do magazines fit in the full sized part?





 

I agree.  It’s an interesting project to do because you can.  However, the costs and reliability issues make it not worthwhile.  Other than testing a new concept, it would be easier and cheaper to mill a lower from 6061.

Ya'll do know there are 3d Printers that do titanium and other metals as well, right?

Doesn't sound any different than bending up your own AK receivers from flats.  People do it all the time, no serial number needed.

I mentioned DMLS earlier.  They are very expensive.  Yes it would work.  Does anyone want an Inconel receiver set?

Ah, I didn't recognize the acronym, now that I look it up I do.  I used to have access to one.

+1

If the ATF finds out, and decides they don't' like you, it'll be a 100,000$ upper, at best.  Kinda fucked up.

ETA: An Inconel receiver would be *bad ass*.  Also, probably 10k or something stupid.

Turbine parts or medical devices?

Hmmm, the scaled down receiver is interesting.  A functioning .22lr of that size would be just too cool.  There would be a huge market for children as well.





 

 

extra "i" there



http://www.ktordnance.com/
 

Someone on this board posted a scaled down build he was doing, I want to say it was 17hm2, but I don't recall for sure.

The geek in me is seriously intrigued....

some of these parts could be plastic...

Be cool to get one of these as an AR pistol up here in NY

Where can I learn more about this lower?

I'd be interested to see how it works.

http://web.archive.org/web/20050524052907/http://www.geocities.com/elmgrove1765/project6/project6.html

Interesting...

None of those pieces alone would constitute a 'firearm' and so you wouldn't need an FFL to order half the kit!