Have you ever wanted a machine that could make almost anything? A machine like this is now becoming easier to own. Desktop 3-D printers are storming the market. A 3-D printer is a machine that can make objects out of plastic, anything from an iphone case with your initials to a fully functional whistle. Essentially, it can make anything you can imagine. 3-D printers have been around for over 30 years but have been primarily industrial and experimental rather than a personal product. Recently, companies have been making 3-D printers that are a lot more affordable. Until recently, they still cost more than $1,500. There are many individuals getting into the 3-D business and trying to design a machine that is both affordable and reliable. A new company has recently emerged with a printer called the Solidoodle that costs $500.
Imagine a machine that is a foot wide, a foot tall and a foot long made of stainless steel. It is like a very precise hot glue gun. It takes plastic filament and heats it up to its melting point, from 210°C - 250°C. A stepper motor, a very precise motor that measures in steps, pushes out the melted plastic filament in a very thin strand (0.3 mm). The strand is approximately the thickness of a strand of human hair. There are different types of plastic you can use. One of the most common ones is ABS (acrylonitrile butadiene styrene). ABS is the same plastic used to make Legos and most toys. You can buy the plastic in 1 kilogram (2.2 lbs.) spools of filament. The current price for a spool is around $45.00. According to the companies, these spools should last you awhile. You can buy different colored spools. Right now you can only make monochrome objects. So if you put red plastic in the 3-D printer, the object will be all red and if you put green, the object will be all green. 
The thin strands of plastic are put on an aluminum plate that is heated so the plastic will stick to it. The 3-D printer then prints layer after layer of your object until your object is finished. How does the robot know what to print? To make something on a 3-D printer, you have to first design it by using 3-D modeling software such as Google SketchUp, Maya or any other modeling software that can save in STL (STereoLithography). You can also go to a website called Thingiverse.com that has thousands of designs that you can download and print.
I think that in the next 10-15 years, most people who already own a computer and an ink jet printer will also own a 3-D printer. Picture wanting to have something and being able to hold it in a matter of hours. 3-D printers are revolutionizing manufacturing.
