Are 3D Printers and ABS feedstock allowed in secure area?
 

I ask because it appears possible to print an AR-15 or other firearm.

While it is probably still possible to sneak a firearm past security at this point (particularly in airports where AIT is being used without magnetometers), one could possibly bring their equipment with them and make one.

It's only a matter of time before the DHS sends out a bulletin warning of a terrorist ring that will attempt to assemble one in an airplane bathroom.

I don't think they made the actual firing chamber out of ABS plastic.

They forbid replicas of weapons, so the firing mechanism is not even needed. Nor is ammo.

As we all know, the armored cockpit door is secretly programmed to open at the mere SIGHT of a replica gun, which is why the TSA needs to ban them.

They didn't print an entire AR-15. They printed the lower, which is the pistol grip, trigger, etc. The barrel, bolt, etc were metal and were not made on the 3D printer.

I'm pretty sure a gun made entirely out of plastic would only work once, and would stand a good chance of injuring the shooter.

I bet you could use a 3D printer to print a working water gun, so I see your point about needing to ban 3D printers, in the name of security.

Have you considered that you may have missed the point and misunderstood what the point is?

Airside assembly of guns from components is already possible. And given the TSA misses guns on the X-ray machines, TSA missing the unassembled components shouldn't be unexpected.

Btw, they also believe that water is explosive.

Unlikely.

For those that have never used or been anywhere near an SDM printer:

The basic steps (at least for my school's Stratasys Dimension printers):
-Design a CAD model
-Use the printer's utility to lay out the components
-Print (read below)
-Lye bath (read below)
-Wash in water and dry
-Assemble

These printers use a different type of plastic as support material, a brittle type of plastic that can be removed by hand sometimes, but some parts have to be put inside a lye bath that dissolve that support material. I dont know if there are printers that don't require it, but if there aren't, well, you need to take something that looks like a deep fryer and some sodium hydroxide to clean this. Quite messy, that's problem #1.

The ABS isn't too sturdy when it gets thin, so you can't make thin components and expect them to be resistant. And if you mess up the tolerances in the CAD file, you've got quite a bit of sanding to do. And the resulting product is not as smooth as something that is injection molded or casted, so you need to sand it down if the ridges will pose an issue.

I have used a 3D Printer before (well, I have had parts printed and watched some of them getting printed). We printed a ~1.5 ft span wing with a chord that was about the same as the length of an iPhone. This was almost a year ago so I don't remember the exact details, but we basically printed out a hollow cylinder, slightly larger than the chord of the wing, and the wing was divided in 2, some additional parts were also printed in there (a small cone for the tip of the cylinder, and some attachments for the wingtips).

In total, it was going to be about 30 hours of printing time, however, the printer failed about 4 hours into the first printing attempt, so it sat idle overnight while displaying an ERROR everywhere, obviously those 4 hours of printing had to be discarded and the printer had to be restarted again.

After that, the parts had to be put in the lye bath (the larger sections had to be printed separately), and I had my parts some 40 hours after the first attempt.

We still had quite a bit of prepping to do, and the lye bath didn't remove all the support material, so we still had some work to do at home.

So based on my experience, I don't anticipate TSA banning these machines, nor people even attempting to run one. They're definitely not that difficult to use, but the process behind is not as simple as some people say, compared to 20 years ago, yes, it's as easy as using an inkjet printer, but the whole process isn't. Think of it as traditional film photography (3D printing) and digital (inkjet printing).

Now, the cheapest Stratasys printer goes for only $9,900, these are the specs.
Size and weight:
Mojo 3D Printer:
63 x 45 x 53 cm (25 x 18 x 21 in)
27 kg (60 lbs)

WaveWash 55 Support Cleaning System:
33.5 x 33.5 x 33.5 (13.2 x 13.2 x 13.2 in)
5 kg (12 lbs)

Maximum Size Part(s): 12.7 x 12.7 x 12.7 cm
(5 x 5 x 5 in)
Volume Capacity: 3.78 L (1 gallon)

So essentially you need all of that plus the chemicals to dissolve the support material, that particular printer seems to use an eco-friendly product instead of lye, but you still need to run it. And if you want anything larger than 5x5x5 then you need a larger printer, which is a lot more expensive, and it isn't really carry-on material. The Dimension printers that we have won't even fit inside the service cart compartment of the galleys, those things are pretty big.

And they can be messy, if an inkjet printer can get messy, imagine what happens when a printer glitches and liquid ABS keeps flowing out of the nozzle. Think ABS cotton candy (I should have a pic of that somewhere).

I don't know if there are better printers that aren't as difficult for this, but I haven't seen / used anything other than that, perhaps someone with industry experience can say something (the roadie???).

This is what we printed before it glitched out, the brown plastic is the support material, the white is the ABS.
http://i.imgur.com/9fLao.jpg

Final parts a few hours after the printer tech gave them to us
http://i.imgur.com/61YfD.jpg

Not all 3d printers require a lye bath - just the high end ones that allow for support material :) I own two that are more hobbyist grade that are much smaller than the Dimension printers - started out a few years with a Makerbot Cupcake, and now I've upgraded to the new Solidoodle 2 (http://www.solidoodle.com/).

Both of my printers have a single ABS extruder. Even being that primitive, they do a surprisingly good job; you can get up to about a 60 degree overhang angle without support material. The printing process is really low fuss - heat the printer to 200 degrees celsius and the build platform to 100 degrees, and then let it do its thing extruding.

Back to the OP's premise, honestly, I find the possibility of a 3D printer producing weapon components airside to be laughable:

- The parts, while sturdy, do have grain from the additive extrusion process. To make a firearm, you'd probably want to do additional machining to ensure they all fit together correctly.

- The build table on my printer is about 6"x6"x6". People do travel with printers my size (http://www.makerbot.com/blog/2010/04...th-a-makerbot/), but the 6" square build envelope isn't super flexible. Making any bigger parts would require a printer that would be much larger than carryon luggage requirements (and therefore wouldn't fit through the xray.)

- These things are SLOW. Slow slow slow. I printed a phone dock (http://www.thingiverse.com/thing:15805) and it turned out great, but it also took three hours of extrusion. If you're printing a gun part, you're going to be sitting there watching it excrutiatingly deposit each layer one by one.

- 3D printers are neat. They attract a crowd - everyone loves to watch them print. Someone's going to notice you loading up "gun-lower-body.gcode" on your laptop, and they're going to wonder why something that looks suspiciously gun-like is slowly being created by your printer.

- ABS is very much not heat resistant - that's the whole premise about how these things work. You'd need to supplement the plastic parts with metal ones - there's a reason plastic guns aren't commonplace :)

I love my 3D printer and it's both a great hobby tool and a great conversation piece...... but it's not an effective weapons factory. There are much, much, much easier threats than manufacturing weapon components airside. :P

Here's a picture of mine printing a whistle. You can see my 13" Asus laptop in the background for scale on the size of the printer, if you're curious - the printer itself is about a 1'x1'x1' cube.

http://i.imgur.com/1Sr7n.jpg?9117

Why would I go to the trouble to 3D print an AR-15 airside when I can get a job with an airside vendor and roll in the AR-15 artfully hidden in the middle of a dolly full of products destined for my airside vendor?

This 3D printer thing is what we call a "movie plot attack".

Ben,

I'm kinda curious about the pattern that's under the whistle, is that something that the machine initially prints and then you can break off, similar to the base made out of support material that Dimension printers build?

So it looks like with a hobbyist printer you can get past how big the Dimension printers are and the issue with the lye bath, but everything else is about the same.

Good question. In short, ABS plastic tends to curl up when it cools, so if you print on an unheated acrylic build surface, you'll have trouble later in the print with uneven layer height. The solution is to print a single, firm zigzag layer at the bottom of the print that exceeds the boundaries of your part; this is known as a "raft". The general idea is that the raft might curl up, but your part in the middle will stay relatively level since ABS likes to stick to other ABS.

The downisde is that you have a funky zigzag pattern you have to peel or cut off your part at the end of the print. This is probably much less of an issue on the Dimension printer since it can use dissolvable support material for the raft instead :)

A better way around this is a heated build platform; if you keep the ABS warm during the entire print, it's under no risk of curling. Mine has a heated build platform - I print on a layer of yellow heat-resistant Kapton tape that sits on top of a 100 degree celsius heating element. With a heated build platform, you don't need a raft at all and parts come out silky smooth on the bottom.

In this case, it was my very first print, and I was using a raft in addition to the heated build platform just to be safe. I've since found it's not necessary, and my recent prints have all been raftless.

Makerbot's instructions have some good discussion of the concept of a raft: http://wiki.makerbot.com/configuring-skeinforge#toc10