3D printing

thumb|right|165px|A 3D printer making a model of a double helix
3D printing, the colloquial name of a digital technology called fused deposition modeling, a subset of additive manufacturing techniques, is a combination of laser printer and polymer injection technologies which can be utilized for small-scale manufacturing of customized parts. The process has been refined since early experiments in the 1980s, to the point Lisa Harouni, co-founder and CEO of Digital Forming, gave a TED talk where she made it clear that "almost anyone on earth can do this sort of thing."For the good of all humankind. While some folks argue that the availability of both inexpensive hardware and software has turned this technology into a potential capital windfall for economies that have seen manufacturing jobs moved off-shore in recent decades (c. 1990-2010),A Brief History of Outsourcing 3D printing as a viable method for curing illness is still in its infancy, and requires massive amounts of capital before it becomes anywhere near viable,James Jeffery "3D printing human organs - but where's the money for it?" The Guardian, 17 July 2013 though preliminary applications, such as low-cost customized prosthesis Ashlee Vance "How About Them Gams: 3D Printing Custom Legs" BusinessWeek, 03 May 2012 and customized orthopedic implants"Transplant jaw made by 3D printer claimed as first" BBC News, 06 February 2012 are already appearing.
With the gradual decline in American manufacturing, it seems almost for-granted that this would be a common sense idea wherein small businesses might spring up to produce goods more economically to replace box-store foreign competition.
3D printing is an expensive method of manufacturing on a per-unit basis. It has the major advantage, however, of costing just as much per unit for one-offs as for lots of ten thousand, which facilitates both small-batch manufacturing and inexpensive prototyping for components designed to be cast or injection molded (which have much lower unit costs but vastly larger capital requirements). This can also make it possible to economically produce one-off parts with the desirable surface finish and other properties of a casting but much less sunk cost by using a polylactide model of the part as a positive for investment casting, as at least one user has done.
As with nanoassembly before it, various futurists are predicting it will turn into Star Trek Replicators at some point in the near future. Any… minute… now…
==Gun control==
The spread of consumer-level additive manufacturing in recent years has fed into the gun control debate in the US. As soon as the technology started to enjoy increasing popularity, people pondered its use in gunmaking. One or two groups have made guns this way. For research purposes, of course. Early designs were primitive and fragile, and even their creators didn't bill them as effective firearms.What happened to the mythical undetectable plastic gun? and Unimpressive 3D Printed Zip Gun Drives Internet Insane Hysterical press coverage following the unveiling of the first printed gun was driven, broadly speaking, by a combination of a desire to build sensational headlines out of "new" technology not yet widely understood and ignorance of how easy it already is to make any given item ( for instance) the "old fashioned" way.
Subsequently, a Japanese enthusiast did fabricate an array of more functional (though ridiculous-looking) handguns, including a revolver, on a 3D printer, though this has generated rather less publicity.
The most functional such handgun to date is likely the crude Hexen Pepperbox revolver, published by a European user under the name Franco. The Hexen's apparent durability results in large part from the use of 6 mm Flobert, known in the US as .22 CB - by a significant margin the weakest gunpowder-driven cartridge in current production.
Developer WarFairy Arms has published designs for an array of receivers specifically designed to be printed in pieces and assembled by the end user. This is primarily a legal issue: on an AR-15, the lower receiver is the component that bears the weapon's serial number and therefore is legally the part that is considered the "gun," with all other parts being accessories. Constructing a lower using home manufacturing skips all regulatory steps such as background checks and waiting periods which would normally be part of purchasing a firearm.
There also exists an IRC community dedicated to, among other things, the design and fabrication of printed firearms, which maintains the primary repository of published designs for them. Organized development notwithstanding, 3D printing appears to have lost its political-football status with the renewal of the .
It is also important to note that while some components, such as grips, stocks, forward grips, etc… can be made by 3D printers, critical components like the bolt carrier, bolt head, firing pin and barrel need to be made in metal, typically steel, to be even remotely practical. A completely plastic gun could fire one round and then break (assuming it does not explode during the first shot), but to fire several rounds a gun requires metal components. Newer plastics, such as carbon fiber reinforced Delrin (Acetron) may have the tensile strength required to cope with lower pressure firearm rounds, but the durability of these materials has been called into question.
A fully functioning 3d printed revolver has been made, requiring only a metal nail for a firing pin. 
An updated version was released in December 2015.
However, metal 3D printers exist, and the company Solid Concepts created a fully functional M1911 pistol made of laser sintered steel (though they appear to have used store-bought springs) that has a quality approximating a traditionally made firearm after hand-finishing of the printed parts. Solid Concepts obtained a license for making firearms in order to comply with US BATFE requirements. While this might seem frightening, the industrial printer used cost between $500,000 and $1,000,000 at the time depending on the precise model, far more expensive than purchasing machine tools and making the weapon the old-fashioned way.
==Innovation in 3D printing==
4D printing is one of the biggest innovation in entire history because it creates an object which changes its shape when external stimuli such as light, electricity, heat are applied to it. 4D printing has many applications in real-time life such as self-assembling shoes and furniture. NASA has developed special flexible material which is used in a spacesuit for astronaut by 4D printing. This isn’t to be confused with printing in the fourth dimension, which contrary to popular belief isn’t time itself but rather the mathematical extension of 3D space by 1 more dimension.
==External links==
* Hackaday
* Makezine
* Instructables
==References==
Category:Technology
Category:Gun control