It’s not a new idea, but in the last year 3-D printing has become newly available: In 2007, when he first started the company within the incubator of Royal Philips Electronics, Weijmarshausen would have paid as much as $500 to print a self-designed iPhone case, for example. At Shapeways today, a designer will pay around $20. This promise recently spurred Andreessen Horowitz to lead a $30 million round of funding in the company.

It’s hard to imagine how a machine could “print” an iPhone case until you’ve seen it. So, last Friday afternoon a group of Fortune reporters and editors headed out to Long Island City for an inside look a the mass manufacturing technique considered so promising that President Obama called it out in his January State of the Union speech.

MORE: Hey Newt, it’s called a ‘smartphone’

The Shapeways factory officially opened last fall, but it’s still under construction. We passed through the administrative area where a half-dozen Brooklyn designer types were fulfilling orders out to the factory floor where nine machines are up and running so far. When the factory is complete, there will be as many as 50.

In front of us, one of these hulking machines gives off heat. It’s the size of a refrigerator; inside, a rectangle tray the size of my favorite chili pan is being filled layer-by-layer with dust. We push our noses up to the small window to watch: A layer of dust is spread. Then, a laser burns a series of lines into the dust, heating it to the point of almost melting to form the object. It will take 24 hours for this chili-pan size tray to be complete.

For now, the Long Island City factory only prints materials in a white nylon plastic, though that will change in time. Shapeways is able to manufacture in other materials — stainless steel, sandstone, ceramics — from its other facilities. The company also has offices in Seattle and Eindhoven in the Netherlands.

A diagram of the tray’s contents hangs to the right of each printer. Weijmarshausen explains that Shapeways maximizes each tray by pairing elements of different customer orders. These diagrams look like a cross between a 3-D sonogram and a katamari. This optimization brings the price down. Once the tray is completed, employees bring it over to a post-production area where they remove all the dust that hasn’t been sealed by the laser. The result is a jumbled collection of parts that are cleaned and separated and buffed, much like bone-hunting archeology. Depending on the order, many are also dyed in bright hues.

MORE: Never forget where you parked again

The 3-D printing buzz has been a bit overblown this year as companies like Staples (SPLS) begin making them available directly to consumers — earlier this month The Cube, which is manufactured by 3D Systems (DDD), went on sale for $1,300 through Staples.com; it will likely be available in stores starting as early as July. But just as with any first-generation tech products, these printers won’t be capable of doing all that much. The fanfare over the world’s first 3-D-printed gun is also a distracting sideshow.

The real potential for 3-D printing will be felt in enterprise — as companies like Airbus explore using 3-D printing to make, say, airplane parts. That’s the bet that fuels Weijmarshausen’s ambitions. As big business takes an increasing interest in 3-D manufacturing, the costs of materials will come down. and the machine technology will improve. Customers will be able to order more types of objects in more materials. Today, perhaps it’s the iPhone case. Tomorrow, potentially, the phone itself.

[cnnmoney-video vid=/video/technology/2013/01/21/t-ts-shapeways-3d-factory.cnnmoney]