What Is It?
In the early days of manufacturing, everything was custom made. If you wanted a desk, you went to a carpenter and ordered one. Your desk might be similar to others owned by people in your town, but each one, crafted by hand, possessed its own idiosyncrasies and distinct features. This process, while well suited to match the individual needs of consumers, represented an extraordinarily inefficient use of time and resources where common goods were concerned. So along came guys like Honore Blanc and Eli Whitney who promoted the concept of interchangeable parts. By using assembly lines to build large quantities of materials to standard specifications, a new era of mass production was born that enabled the industrial revolution. Eventually, most of us started ordering our desks from Ikea.
Today 3D printing, or "additive manufacturing," is swinging the pendulum back to the era of custom consumer products. Using digital data from a regular computer, 3D printers a little larger than a hat box can build virtually any solid object you conceive of from a variety of materials (though plastic is most common). Since they were developed around 2003, the cost of the mini manufacturing units has gotten lower and lower, while ease of use and accessibility continue to rise.
How It Works
The nascent technology works with 3D image files that can be created using a wide variety of programs, from Google SketchUp to Adobe Illustrator. The files, often large in size, can then be sent to the printer using a standard USB cable. 3D Printers are so called because they create objects layer by layer, similar to the way a printer creates text and images line by line. The material used is melted down and poured through an extruder in the appropriate pattern, and then additional micron-sized layers are added until the three dimensional object takes the appropriate shape. Depending on the size and density of the object, the process can take from a few minutes to a few hours.
You don't have to be a drafting expert or industrial design grad to create something that can be made with a 3D printer. An online community called Thingiverse collects pre-rendered designs of all sorts of things, from sunglasses to salt and pepper shakers, that were dreamt up and generously donated by crafty makers from around the world.
The larger the 3D printer, the larger the objects that are possible and the larger the price tag. A 3D printer that you might buy for home use will typically make objects up to about six inches tall. An industrial printer that might be used in a lab could theoretically build objects much larger. The most common types of plastic used to create objects are ABS, which is what Legos are made of, and HDPE, which is used in milk jugs. 3D printers that can use metal are currently under development. Some printers available today can even be customized to work with frosting in order to create edible treats.
Where You'll See It
3D printing has grand implications wherever custom manufacturing is concerned. One example is the case of prosthetic limbs and even artificial organs. Today, a replacement arm or leg that is well matched to its natural counterpart can be prohibitively expensive to manufacture. With 3D printing, a perfectly matched limb built using MRI data could be produced at a lower cost with much greater specificity. Scientists are already envisioning the day when a machine can construct a new organ by assembling layers of human cells to form the appropriate tissue.
On a smaller scale, a 3D printer can be a reality today for anyone willing to shell out a little over a thousand bucks. MakerBot Industries, proprietors of the Thingiverse, make the cheapest, most user-friendly 3D Printer-- the Thing-o-Matic -- which is available on their website for $1,299 (some assembly required). For those who don't want to deal with the hassle of owning and operating their own 3D printer, an online service called Sculpteo will print and ship your three dimensional object for you using your own specifications and state of the art printers. Sculpteo calculates its fee on an item-per-item basis based on the size of the object and its level of detail.
Check out a MakerBot in action at CES in the video below.