DEARBORN HEIGHTS, Mich. -- Ten years ago, Ford 3D-printed perhaps 4,000 prototype parts for its vehicles. Today, just one of the automaker's five 3D prototyping centers churns out more than 20,000 parts annually.

The reason for the explosion in 3D printing (or additive manufacturing) of vehicle parts is twofold: As consumer 3D printers have grown in popularity, printer makers have been infused with fresh revenue, which has been used to improve industrial machines and processes. And secondly, manufacturers have become proficient at creating prototype parts, so much so that the work can be done in hours instead of the four to six weeks needed with traditional machine tooling processes.

And time is money.

Ford technologist Leron Jones pulls sand molds from a block after a printing. Jones vacuums the excess sand away from the molds (on top). Sand molds for making metal prototype parts used to take up to 10 weeks. Today, it can take about a week to produce hundreds of molds on a single machine.

"Companies like 3D Systems and Stratasys are spending huge amounts of money on development. So not only are machines and materials getting better, but the process is getting faster and it's helping drive the overall cost down," said Harold Sears, a technical specialist in additive manufacturing technology for Ford.

In fact, without 3D printing, the Ford Motor Co. simply would not be able to meet its new model vehicle build deadlines, according to Sears. The company is today dependent on 3D printing to invent new vehicle parts.

A row of stereo lithography (SLA) 3D printers at Ford's Dearborn Heights facility. SLA printers use a laser to draw out a pattern in a photo-reactive resin. As the laser strikes the resin, it hardens it. SLA printers offer the finest resolution for 3D printed parts.

"Everybody wants to know how much 3D printing has saved in dollars, but when you're talking prototypes, it's time," Sears said. "What would bringing a product to market a month early do for you? That's millions of dollars. It's not something that's easily measured."

Before 3D rapid prototyping, manufacturers had to send blueprints to a machine shop, which could take weeks to produce a part. Once the part was delivered, it would often have to be modified, which would require successive models for the machine shop. Today, engineers use CAD software to draw parts, which are then downloaded to 3D printers that can turn them out in hours. If modifications are needed, they're made on the CAD drawing and simply reprinted until they're correct. Nothing needs to go offsite.

Ford's 3D printers range from something the size of a large refrigerator to a small truck. The 3D printers range in price from $250,000 to high six figures.

While 3D printing is relatively new to the consumer market, manufacturers like Ford have been using it for nearly 30 years. In the mid-1980s, Ford went live with what was only the industry's third stereo lithography 3D printing machine.

A block of powdered silica hides what can be 100 prototype parts printed with laser sintering technology.

Computerworld reporter Lucas Mearian pulls a prototype interior door panel part from the block of powdered silica.

Today, Ford makes use of nearly a half dozen types of 3D printing methods, including stereo lithography (SLA), selective laser sintering (SLS), fused deposition modeling (FDM) and a lesser-known process known as binder jet printing, where layer after layer of sand are epoxied together to create molds for metal parts.

Of Ford's five 3D prototyping centers, three are in the U.S. and two are in Europe. At its Dearborn Heights, Mich. facility, 14 different industrial 3D printers turn out 20,000 parts a year. A single print run on one machine can create anywhere from a few parts to hundreds.

For example, in its laser-sintering lab, several machines perform rapid prototyping of parts by melting hundreds to thousands of successive layers of fine silica together. What emerges from the printer is an amorphous block of powdered silica from which dozens of hardened parts are removed by hand and cleaned with a brush and vacuum.

Some of the prototype parts created, such as engine air intake manifolds and oil pans, are made with special nylon. Those nylon parts are often used to replace conventional parts on working vehicles, which are then driven tens of thousands of miles to test them for production. Test results are used to modify the production parts.

Ford's Harold Sears shows off an engine air intake manifold created by 3D printing.

Similarly, in the 3D Sand Printing Lab, binder jet printing machines churn out large bins filled with 100 or more molds into which molten metal will later be poured to make metal prototypes. A single binder jet print run can take as little as a week to as much as a month, depending on the job size and deadline. Conventional sand molds would take eight to 10 weeks, Sears said.

"We're improving quality too. We're giving engineers the ability to optimize their time. They've still got a deadline, but we're giving them better tools to make sure it's done right," Sears said.

Inside Ford's 3D Prototype Printing Lab

Lucas Mearian covers consumer data storage, consumerization of IT, mobile device management, renewable energy, telematics/car tech and entertainment tech for Computerworld. Follow Lucas on Twitter at @lucasmearian or subscribe to Lucas's RSS feed . His e-mail address is lmearian@computerworld.com.

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