Back in the discussion of 3D printing an AR lower, AmericanLoki requested that I start a new thread once it came time to actually test my printed lower.  Well, I finally got around to the testing phase over the past few weeks.

To recap, I have an old Stratasys 3D printer (mid-to-late 90s machine, but works fine) and early last summer I printed a modified version of the lower from cncguns.com (I beefed up the front takedown lugs, bolt hold lugs, and added an integral trigger guard):


(the white one was a 75% scale version of the unmodified lower done as a feasibility test)

I assembled it first into a .22 pistol:


It's had over 200 rounds of .22 through it so far and runs great!  To the best of my knowledge, this is the world's first 3D printed firearm to actually be tested, but I have a hard time believing that it really is the first (if anyone can point me to earlier work, it would be much appreciated).

But you guys want more than rimfire, I'm sure.  Last weekend I finally re-assembled a .223 upper and gave it a go:



No, it did not blow up into a bazillion tiny plastic shards and maim me for life - I am sorry to have disappointed those of you who foretold doom and gloom.



However, it is giving me feed and extraction issues.  As these issues persisted when I switched over to a standard aluminum lower, my problems appear to be with the upper.  I'll give it a good cleaning/oiling and try it with some brass cartridges instead.  Nevertheless, yes - a 3D printed lower is entirely usable.  My model could stand to have a little more material on the buffer tower, but I'm extremely pleased with how well it's working so far.  Further details on the construction and intial .22 testing are on my blog:
http://haveblue.org/?p=1041
http://haveblue.org/?p=1321

Also, keep an eye on oryhara's work on printing AR lowers - I think he may soon become the leading authority on the matter:  http://rommie.digitalcrowbar.net/wordpress/

Very cool. What is the media made out of? Do all 3d printers use the same media or is it product dependent?

This is very cool. Can you give a rough price on what it cost to make? I'm sure there can't be more than a few dollars in actual material in it. I know the machine to make it can't be the cheapest though.

Very cool. Are the pins showing any signs of stressing the receiver? Or are there any other points wearing visibly?

Thats pretty cool

Looks good.  If your pin holes start to egg consider using bushings.

CMS

Congratulations on your successful test.  I could see this as a way to test new lower designs among other applications.  Well done...

amazing

Do you have a direct link to the file you used to print your lower?

Thanks
Wes

pretty slick! not sure i'd trust it for a full size centerfire rifle but a .22 i'd do for sure. i'm assuming it's delrin your using? that stuff is pretty tough.

How long until a 3D printer is considered constructive intent?

TRG

This is the future.

If we can spread this core technology to every kitchen tabletop, there will no longer be a meaningful way to restrict and infringe on the private civilian ownership of modern firearms.

Thread is oh-so-tagged.  Nice work, OP.  



It won't be.  The technology is so wide-spectrum in application and so abstract in essence that it would be like the FDA declaring tapwater to be tightly regulated as a medical substance.  People, groups, and industries from all walks of life would descend upon them in wrath and fury and nothing would be left behind except maybe a warning to other parts of the bureaucracy to not be as foolish.

Riddle - the material is ABS plastic.  Unfortunately, I don't know which specific resin, but it's similar to SABIC MG47 or Stratasys P400.  It is not as strong/durable as a composite lower made of glass filled Nylon 66, but I'm seeing what other materials I might be able to use.

MPD142 - I believe I paid about $100 for the spool of material this was printed from (closeout price), and I used perhaps a tihird to half of the spool.  The cheaper (yet more finnicky) PA-747 based material used in RepRaps, Makerbots and the other low cost printers exploding onto the market would bring the cost down to perhaps $10 each worth of material.  It will only get cheaper.

phurba and cms81586 - my original idea was to sleeve the holes with brass tubing to act as bushings, but the pins fit in quite nicely, so I'm running it as-is for now.  The only wear I'm seeing is a little bit of back-and-forth movement on the hammer pin, only perhaps 10 thou.  I'll keep running it and see if it wears further, or if that's the extent of the break-in.

Wangstang - I posted the .STL file on Thingiverse: http://www.thingiverse.com/thing:11770

fatkid35 - I don't believe I've seen acetal (Delrin) available in filament form that could be run through a 3D printer, but it is certainly up to the task of serving as a lower when machined.

That is awesome! I have a friend with a 3D printer, I never thought to ask him if this was possible... I have to grab a 12 pack and go talk to him!

I can't wait to see how this develops.  What other receivers would be feasible to print in such a machine?

very cool!

I have a MakerBot, but have yet to print anything...having calibration issues. While I'm glad the printed lower worked fine with your testing, I would be very scared to use a printed lower myself. The plastic is like the plastic used to make LEGOs, so cracking is a very high possibility over time. Printed parts are great for test-fitting new designs or changes to existing designs, and seeing an actual functional printed lower is very exciting indeed...just be safe! Keep us updated on how things go!

how does it compare, weight wise, to a standard aluminum lower?

i know a lot of the resins that were the laser sensitve resins used in many 3d printers would break down over time.

very cool that it works

Wow!

I once had the chance to see a small company's "rapid prototype" machine and it gave me ideas along these lines. Very cool, keep us posted.

It depends on the resin, and there are a number to choose from. Even if a printed lower fails, it's unlikely to be a catastrophic failure in the sense of injuring the shooter. Since the kerplosion is entirely contained in the chamber, it is possible that the lower would splinter (and possibly be dangerous in that respect) but it's not like its trying to contain the pressure of the round going off.

Incredible
 

Where will we be in 10 years?


Neat stuff ! ! !

Nice!  Did you print the threads for the buffer tube, or undersize them and tap yourself?

If so, did you have to play with the toolpaths/raster thickness to get them to come out right?

We just got a pallet of black ABS at work... I might have to... uhh... get the machine set up to use it

Very cool.

Your post makes no sense to me.  Are you arguing that because it will become easier to manufacture a firearm that the ATF will no longer try to regulate it?  I call BS, and I can see them taking great interest in this thread.

This is a hot topic on the 3D printer forums. Some people want to make plans for gun parts readily available, either to prove gun laws irrelevant or to circumvent them; while others feel that guns are icky and no such thing should happen.

Anyone who knows me here knows that I am hardly an advocate for gun control, however it is simple for an ineligible person to print a gun and buy the non-gun parts online. Is that something that could be regulated? Not really, unless you regulated the printers. The easiest way to control that is to stop the plans from being posted on public forums. But lets be honest here: anyone who wants to circumvent these laws could go learn machining and mill their own AR receiver, and the same thing goes for learning CAD software and running a polymer printer. Does that mean that machinists classes and forums should be regulated? Certainly not. I really feel the same argument applied to 3D printers: basically, there's nothing that anyone can nor should do.

I honestly didn't realize that you could manufacture a firearm without filling out any forms until just now.  In that case...PRINT AWAY.  I wasn't even thinking about restricted persons.

Wow.

That's the future.

So, do you have to add a serial number?

Assuming it follows the same laws as finishing an 80% lower, no, it is not required, though it is recommended. The same regulations regarding manufacturing of course would apply - building for personal use only. Occasional sales (as in because you got bored with it) would be permitted.

awesome project I would love to know more about this material
keep torture testing the lower

I believe that the ATF would run afoul of the 1st Amendment if they tried that.  IIRC there was a case some years ago where some scientific journal won a court case on 1st Amendment ground when they printed or wanted to print an article on how to build an atomic bomb.


Vulcan94

I'm way too stupid to fully wrap my head around 3D printers.  So basically, I consider this some sort of magic or witchcraft.


Very cool.  I have way too many questions to ask, but I should probably read up on 3D printers to get an idea of what exactly is going on.

Now do you want to test fire it with a 3D upper as well? 3D Printed Upper

Awesome to see one tested. I wanted to print a lower rather than the upper, but I didn't think that would go over to well at college with it technically being a firearm once printed.

So you guys can print buttstocks, pistol grips, etc?  

I know what I want for Christmas; a 3D printer!

Nice, glad someone finally got around to it

Let us know if it starts to fatigue and crack around the buffer tower.  I don't see it blowing up in your face, but it probably won't last forever

Depending on the type of polymer, it may run for years with no problems, though.

I'm getting my printer put together, a MendelMax. Still waiting on a few parts. Once it is done and calibrated, I'm doing this.

Just youtube MakerBot or 3D printer and you can watch all the amazing things these things can do. Cool thing about 3D printers is you can print a lot of the parts that are needed to build one, so in essence, you can almost print a factory of 3D printers...minus the extruders, power supply, axis guide rods, and other metal and electronic parts, of course.

I will be using my MakerBot to print prototypes and not actual final pieces for actual use.

Let us know how much the MendelMax ended up costing you, if you don't mind sharing. I bought a MakerBot and am looking to try other 3D printers as well. Once I get my extruders calibrated correctly, I will try to print some pieces to make another 3D printer. Right now my MakerBot is nothing more than a monotone rock concert with a light show...lol

Very cool.

It cost Just over $1,250 for a complete kit. The guy who was selling the MendelMax kits just merged with Trinity Labs. There was a bit of a delay due to backorders, but they have since worked out most of the supply issues. Since you've already got a printer, look up the printed parts for the MendelMax 1.5 on Thingiverse. I really like the Misumi aluminum extrusions, they make the machine rock solid. As it stands right now, I've got the entire printer frame out together and am waiting for the last parts for the hot end and extruder to arrive.

Only real problem for durability here is one of heat.  A printable plastic (ABS melts about 230C, PLA at 205C) is too low-temp for sustained use in a firearms application like this.

Keep temps down, or it'll start melting near the hot bits.

Completely usable and fun if you keep the ROF (hence, temps) down.

Licensed 07s, would have to embed a metal plate to carry the required serial number.

I had to scan through a few articles this morning to get the gist of what they were capable of , for now at least . It was kinda similar to what I was thinking . The printers now look like they are limited to materials that are easily 'extruded' . I didnt actually see the printer running in any of the vids I watched , but I'm assuming it works like a precision . . . uh . . . caulk gun , I guess . . . squirting out the molten material , back-and-forth . . up-and-down, building up a programmed shape , kinda like decorating a cake with a CNC . . . . I think .

The sintered metal units will be great once they come down in price but it's going to be a while before most folks have them in their garages . Watching Jay Leno talk about them at the link posted ( in this or the other link-thread) , he makes it sound a little more useful than it is at this point . For decorative body parts like scoops and trim pieces , it's great and the parts made could be used as they came off the printer , however , the steam engine parts like he was playing with would only be useful as test-fit items and reference pieces . The scanned dimensions could be passed on to a machine shop to be milled and turned from steel , but an item made from the ABS or whatever,  has no strength or heat/corrosion resistance . . . . for now .

The AR15 lower is kinda stretching it's limits , you'd not make an upper that could withstand the pressure , at least not yet Still , it's very cool and extremely promising with all the directions you could go .

As far as the manufacture of firearms goes , I dont think these machines will force any law changes , one way or the other . It's still just a matter of making something , whether it be a decorative widget for your daughter , or a suppressor baffle for your buddy in the militia . . . .somethings are GTG , and some are verboten .

Laws are laws , and they're already in place to say what you can and cant make , and what you can or can't do with it once it IS made . I dont think the ATF is going to care HOW you made the suppressor baffle , but the fact that you made it in the first place . Whether you hand carved it with a Dremel and file , spun it up on your bench-top Southbend , hammered it out from a store-bought washer , or spit out 400 an hour from your $400 antique screw machine or $400,000 CNC turning center . . . . the baffle is still illegal to own without jumping through the proper hoops .

I sure as hell hope not... I don't doubt that it works but damn craftsmanship is going to shit

So you are saying you think this technology will become as pervasive as shoelaces?

TRG

Just YouTubed some videos.  That is some wild stuff.

I wonder if someday, they'll be able to use some sort of super durable plastic in a 3D printer.  Glock frames, anyone?

Have you tried the "throw it down the driveway" torture test yet? Please YouTube it!

Awesome, just simply awesome. The wave of the future.

Did you have to thread the holes, or is the resolution fine enough to recreate those as well?





Excellent work!




 

Maybe it's just me, but posting pictures of an operational lower reciever that doesn't have a serial number....That just sounds like your asking for the feds to pound on your door.

Either way, it's still pretty cool.