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Solid Concepts Manufactures First 3D-Printed Metal Pistol
Zothecula writes "In a prime example of past meets future, a Texas-based company has used a century-old classic firearm as the blueprint for the world's first 3D-printed metal gun. Solid Concepts' use of a laser sintering method to create a fully functional Model 1911 automatic pistol is the latest demonstration of the potential of 3D printing techniques in industrial processing. The company's 'The gun proves laser sintering can meet tight tolerances. 3D Metal Printing has less porosity issues than an investment cast part and better complexities than a machined part. The barrel sees chamber pressure above 20,000 psi every time the gun is fired.'"
better complexities than a machined part.
But weaker parts.
When making metal parts the the metallurgical properties are more important than the shape. The direction of the molecules in the metal make the difference between something that's hard and brittle vs. something that's soft and elastic.
I work with a lot of different rapid prototyping processes - including DLMS - on a weekly basis. In their current form you cannot change materials mid-part on a DLMS machine. Even if the machine itself could handle it (i.e., had multiple material-handling streams), you would have a tough time getting the dissimilar metals to properly fuse. As a welder how good the results of welding aluminum and steel are, or titanium and steel. Mixing these metals tends to result in brittle intermetallic phases, which are perfect places for fracture. Even worse is that, because the machine works layer-by-layer, the boundary between the two metals would be planar, making fracture all that more likely.
What is more, because the process is akin to SLS, what you end up with is a box - the build envelope - completely filled with powder, inside of which is the part you've made. You can ordinarily reclaim most of the powder and use it again. If you were to change materials mid-stream, you would have to junk most if not all of the leftover powder, because you wouldn't have a good way to separate the powders.
For the same reason that they refer to intermediate cartridges as "high power": journalists are morons.
Well, not exactly. It protects against many more threats than just criminals with firearms. It protects against anyone that seeks to do substantial physical harm to you or your family regardless of their means (aka baseball bats, lead pipe, brass knuckles, etc.)
As for the last assumption, you are most likely referring to the Kellermann report which stated that a firearm in the home is 43 times more likely to kill a family member, friend or acquaintance. That report has been debunked many times as it specifically excluded most accounts of self defense and included suicides and even police actions against criminals in the statistics. And of course these are all statistics 30 years out of date, where the murder rate of US citizens has steadily declined to less than half of what it was in 1986. (despite what the media portrays)
I've been trying to sort out the "guns" issue from a scientific point of view. After some extended searching, I believe the answer is "more guns is better".
This is made enormously difficult by the vast ocean of misinformation put forth by advocates on both sides of the issue. It's an interesting exercise in clear thinking just to sort through the claims to come up with an opinion unfettered by bad logic. I've included some examples below.
In summary, the best measurable statistic appears to be "chance of death from all causes" at the national level. This statistic avoids most of the bad math and bad thinking, and it's easy to measure and verify. The US does not have good health care, and this [national] attribute has a large effect on the mortality rate unrelated to gun-related deaths, so you can't use the US for comparison purposes at the national level. A better comparison is made between two countries with similar national health care and different gun policies. England and Switzerland, for example.
Comparing England and Switzerland indicates that "more guns" is associated with "less mortality". This echoes comparisons made within the US at the local level, where areas with public access to guns have less crime and mortality.
It's pointless to debate the issues in this forum due to the enormous and convoluted "poor statistics" cited by people on both sides of the issue, and virtually everyone is cognitively dissonant and emotionally invested in the answer.
A good analysis of the issues can be found here.
Below are just a few examples of popular claims, and how they mislead the reader into one side or the other. There are misleading claims on both sides, so don't read too much into the choice of examples.
Example 1: "Guns do not make a nation safer, say US doctors who have compared the rate of firearms-related deaths in countries where many people own guns with the death rate in countries where gun ownership is rare." (source) (False comparison: when gun ownership goes down, deaths due to other causes rises.)
Example 2: England has fewer gun-related murders, but a much higher rate of beating murders. (Undecidable: In the US, a non-suicide gunshot victim is automatically a murder, in England it's not a murder unless there's a trial and conviction.)
Example 3: If you have a gun in the house, you're more likely to accidentally shoot a family member than a burglar. (Wrong statistic: Having a gun depresses the chance of crime for your neighbors, the overall gain in safety for the community may be more than the loss of safety for the individual. See Polio vaccine.)
You talk about designing new launch vehicle engines and then you say the sky's the limit.
Your rockets are in a lot of trouble, sir.
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The thing is, people make their own guns all the time in gun fans' equivalent to makers meets. They use a combination of tecniques. You really want the barrel and receiver to be forged, not cast. But you can take roughed-out forged parts and them CnC mill them to perfection, and get the strength easily enough.
There's little point in trying to CnC mill the entire gun, but a combination of forged blanks, a rolled tube for a barrel, some milling, and simply buying all the other pieces mail order (they sell kits for this), and you have a perfectly serviceable AR15 with no serial number. In most places that's perfectly legal, as long as you've avoided any legal landmines along the way and especially that you never sell it.
That's the thing, legally. In most places in the US you can legally make your own gun, but making a gun for someone else makes you a firearms dealer. People are arguing over where selling the code to allow someone to make a gun automatically lands, legally (if you follow kit cars at all, you'll find this all familiar).
Outside the US, in places where you can't legally make your own gun, this is a much bugger deal.
Socialism: a lie told by totalitarians and believed by fools.