Mr. Yee, what about banning pressure cookers? We've just proved even morons can make effective explosive devices out of pressure cookers!

... but they'll have to walk barefoot across a huge room with a floor littered with thousands of loose legos first!

I'm pretty sure black power is just sulphur, charcoal, and saltpeter... and that's without bothering to even google the recipe. People have been casting their own bullets out of lead for hundreds of years now. Machining your own brass shell casings is probably more trouble than it's worth, but there are literally billions of them already out there, and they are generally reusable. Hardest part to make is the primer, but understand those are made out of mercury fulminate, which my dorm mate made in his room in college -- and he was a computer scientist, not a chemist. Wan't to skip all the complicated stuff, go back to using single-shot muzzle loaders, preferably flintlock. 200 year-old technology pretty easy to replicate today. And most likely pretty easy to make one that won't trigger a metal detector.

Mostly plasting, except for the metal end carrying the primer, and of course the metal shot inside. But yes, I'm sure somebody has by now made non-ferrous ammo to go with the non-ferrous guns that have been around for a long time. In fact, ceramics are pretty strong now. I wouldn't reuse them like brass shell casings, but I'm pretty sure they could be designed to survive a single shot.

Zip guns are single-shot. Printed guns take clips and are multiple shot until they jam, which should happen within the first few clips. Both are fun toys, but nothing I'd bet my life on when a Glock or Walther PPK are still relatively cheap.

Nobody buys a $1000 3D printer to make just one item, just like nobody plants a field of marijuana to get just one joint. Yee doesn't want the people that now go into the drug business to go into the gun illegal gun parts manufacturing business. But Pandora's box is already open, and stuffing everything back inside is now impossible... existing 3D printers can be used to make more 3D printers, in fact most 3D printers come with blueprints to replace easily warn parts and recommend that he first thing you make is spare parts!

Kind of like Restraining Orders... because obviously anybody planning on breaking the existing laws against assault and/or murder is going to totally change their mind when a judge says coming within 100 yards of their intended victim is now against the law!

Practically ALL rapists have male genitalia... let's outlaw having male genitalia!

A homemade gun is a lot less reliable than a cheap firearm, and no harder to trace than any weapon with the serial number filed off. Wait, don't tell Lee that, or next he'll propose outlawing files!

My coworker is a lot smater than Leland Yee-haw, and has figured out that the best way to make knife blades is by taking old hardened carbide steel files and grinding them down. I check his prototype, and yes, it had a much better edge on it than you could possibly get with a 3D printer. And yes, anything you can make with a 3D printer you can make much better with a full machine shop, provided you know what you're doing. When I was in college, my dorm mate went down to the local chemical store and bought everything he needed to make pyrotechnics (ok, the mercury for the mercury fulminate he made was stolen from the college chemstry lab). Kids can't do that anymore, because lawmakers can't tell the difference between pyrotechnics and explosives. Every fireworks display uses mortars, with the same name and principle of operation as the mortars used on the battefield. We now strongly discourage all Americans from learning how to make things for themselves, and as a consequence the Chinese are now much better at machining than we are.

I though .22 gage zip guns were made from car radio antennas... silly me. Yes, some steel pipe would be a lot more sturdy.

Does Leland Lee really not realize you can use a 3D printer to build a 3D printer?!?

http://www.youtube.com/watch?v=ng-l4gdoSQE

Oracle has a HUGE economic interest in making sure MySQL sucks bad enough that customers buy Oracle databases instead.

$1600 seems an awful lot to pay for being a fanboy. Actual developers should be having their company pick up the expenses. Who pays the expenses of fanboys?