Technicians at General Electric weld together as many as 20 separate pieces of metal to achieve a shape that efficiently mixes fuel and air in a fuel injector. But for a new engine coming out next year, GE thinks it has a better way to make fuel injectors: by printing them. To do it, a laser traces out the shape of the injector’s cross-section on a bed of cobalt-chrome powder, fusing the powder into solid form to build up the injector one ultrathin layer at a time. This promises to be less expensive than traditional manufacturing methods, and it should lead to a lighter part—which is to say a better one.
Unlike machining processes, which can leave up to 90 percent of the material on the floor, 3-D printing leaves virtually no waste—a huge consideration with expensive metals such as titanium. The technology could also reduce the need to store parts in inventory, because it’s just as easy to print another part—or an improved version of it—10 years after the first one was made.
Aerospace companies are at the forefront of adopting the technology, because airplanes often need parts with complex geometries to meet tricky airflow and cooling requirements in jammed compartments. About 20,000 parts made by laser sintering are already flying in military and commercial aircraft made by Boeing, including 32 different components for its 787 Dreamliner planes
Buildup: GE made the aircraft engine component on the left by using a laser to melt metal in precise places, beginning with the single layer seen on the right. Credit: Bob O’Connor
* Using 3-D printing to corrugate the insides of some parts can reduce their weight by up to 70 percent, which can save an airline millions of gallons of fuel every year. That prospect has GE looking for ways to print everything from gearbox housings to control mechanisms. “We’re going on a major weight-reduction scavenger hunt next year,” Rockstroh says.
* Automobiles could similarly benefit from lighter parts, and the University of Louisville’s Gornet notes that printing processes could cut the weight of valves, pistons, and fuel injectors by at least half. Some manufacturers of ultraluxury and high-performance cars, including Bentley and BMW, are already using 3-D printing for parts with production runs in the hundreds.
The time it takes to produce a part will have to improve as much as a hundredfold if 3-D printing is to compete directly with conventional manufacturing techniques in most applications.
Only a handful of plastic and metal compounds can be used in 3-D printing. In laser sintering, for example, the material must be able to form a powder that will melt neatly when it is hit with a laser, and then solidify quickly. The compounds that meet the necessary criteria can cost 50 to 100 times as much by weight as the raw materials used in conventional manufacturing processes, partly because they’re in such low demand that they’re available only from small specialty suppliers.
Computerworld – Declining prices, improved quality and easier-to-use software are opening up demand for 3D printers. Commercial models — capable of cranking out industrial manufacturing prototypes — that once cost $100,000 now start at about $15,000, while personal 3D printers for the hobbyist and education market sell for less than $1,500.
Faster product development
Ben White uses a 3D printer from Z Corp. to produce prototypes of window curtain poles, tracks, blinds and other hardware for Integra Products Ltd. “It’s more economical to lease a printer than it is to keep sending products out for fabrication,” says White, senior product design engineer. “We’re at 10% to 15% of the cost of the service bureau,” he says, and the turnaround is faster and the models are more accurately rendered to the original design specifications. After six months, the company is using the printer to produce 95% of its prototypes.
By using an HP DesignJet for rapid prototyping, Tintometer Ltd. sped up its product development times by 40% to 60%, says industrial designer Amy Penn. And the company, which manufactures industrial instruments that measure color, also uses the 3D printer to build finished products.
After seeing what a 3D printer could do, Ed Fries, the former vice president of Microsoft Game Studios, started up FigurePrints, which uses Z Corp.’s ZPrinter machines to create one-of-a-kind models of personal avatars for World of Warcraft and Xbox Live game enthusiasts.
FigurePrints downloads the characters directly from each game site, and lets users pose them before placing an order. An artist then cleans up the object, smoothing away the series of polygons that describe the figure and adding a third dimension to some 2D elements of the image, such as a cape and hair
It costs about $5 per cubic inch to print a figure, not including pre- and post-processing time. FigurePrints sells the characters for about $15 per cubic inch — and users seem willing to pay. “A common request is for wedding cake toppers,” Fries says. “Couples meet in the games and want their characters on top of the wedding cake.”
Niche versus Mainstream
In 2010, there were over 44 million traditional 2D printers shipped worldwide, according to IDC.
There have been only 51,000 3D printers sold worldwide since 1988 and 2.7 million solid modeling CAD seats worldwide, Wohlers estimates that there’s plenty of room for growth. By 2015, Wohlers expects, shipments of industrial 3D printers will more than double to 15,000 units.
Stratasys expects to cut total pre- and post-processing time for a typical print job in half, from 5 hours today to about 2.5 hours within the next three years, and for prices to drop from today’s $15,000 for its entry-level professional printer to between $7,000 and $10,000 in that same time frame. “In three to five years, you will have the same capabilities for under $5,000,” he says.
In the personal printer space, says Lewis at 3D Systems, prices will drop even further. “In the next year or two, you will see us go past the $1,000 mark. In two years, we’ll be close to $500,” she says.