Hall 11 at the Frankfurt Messe has over 23,000-m2 of exhibition space, so when you walk through the outer doors, having passed all those huddled guys caging a smoke in the early December chill, it comes as something of a surprise to see that it is filled with an array of technologies for product development—fast product development, in particular—with areas and exhibits featuring simulation, virtual reality, materials, additive manufacturing, design, and more. It’s Euromold 2011, and while there are two other halls that contain, primarily, machinery, software and related equipment and services, it is in Hall 11 where you find the sorts of technology that help get products to market faster.
Some of these things are comparatively small. Like the FreeForm Pico 3D printer from Asiga (asiga.com), a machine that uses LED-based UV light to produce parts within a 30 x 40 x 100-mm volume, a machine that can provide an X, Y accuracy of 37.5 microns and 1 micron in Z, a machine that looks like and is about the size of, a Keurig coffee machine (it measures 220 x 225 x 505 mm). The guys from Asiga are a long way from home in Santa Ana, CA, but they are displaying their machine in the hub of digital fabrication during the four days of the event.
Nearby, there is a bigger machine, a much bigger machine, a machine that is more like a full-blown machine tool than something as visually delicate as the Pico: the voxeljet VX1000 (voxeljet.com), which features a print head with 10,624 nozzles; the machine’s outer dimensions are 2,375 x 2,800 x 1,980 mm, which makes it about 10x the size of the aforementioned Pico. It has a print width of 1,060 x 600 x 500 mm, and thanks to the nozzles, it can apply a 100-micrometer layer of polymethyl methacrylate (PMMA) that’s 450-mm wide in 30 seconds. (As there is a considerable, and visible, environmental initiative in Germany—and voxeljet is based in Friedberg—the use of an inorganic binder for the part build is noted. Grün is gut.)
There are printers—or “additive manufacturing systems,” as some are wont to call them—that make parts out of metal, like the equipment from Arcam (arcam.com) that produce parts with electron beam melting of titanium alloys and other metal powers. Then there are machines like the BluePrinter (blueprinter.dk) that uses a process called “selective heat sintering” to build thermoplastic parts in its 160 x 200 x 140-mm chamber with a thermal print head. (A couple of interesting aspects of this machine: one is that the model being built doesn’t require any supports as it is surrounded by reusable powder (i.e., unmelted) in the build chamber; the other is that it has a 100% web-based interface, working with Windows, Mac and Linux—as a spokesman put it, “We hate installing drivers.”)
“I don’t know a lot about a lot of things, but I know a lot about cutting metal,” says Dave Burns, president and COO of Ex One. Ex One is a company that specializes in 3D printing of functional metal parts as well as cores and molds for sand casting. Burns, prior to joining Ex One, had extensive experience in gear-making processes and equipment, in cutting metal with complex shapes and precision. So with that knowledge as prelude, he rhetorically asks, “What if you had no manufacturing constraints?” And he goes on to explain that metalcutting manufacturing processes are predicated on the limitations of the equipment and tooling. For example, you start with a block of metal and then cut it with a tool on the end of a rotating shaft (as in milling). While there is the possibility of moving that shaft through many points in space, there are still limitations predicated on such things as fixturing. Which is a constraint. But “What if you had no manufacturing constraints?” Wouldn’t it be possible—conceivable, do-able—for parts to be designed such that they’re optimized for functionality because they’re not machined but printed, in metal, directly from CAD data?
While there may be some time considerations—after all, people have been working at optimizing throughput in metalcutting for at least a couple hundred years—Burns suggests that there are considerable inefficiencies in the production of some components (e.g., volute shapes) that can be readily overcome by the 3D printing approach.
And now he knows a lot about that.
Nikolai Zaepernick is talking about global warming. About CO2 emissions. About the Euro 6 standard. About sustainability.
You might think that he’s with an auto company trying to figure out how to deal with social and regulatory environmental demands.
But he’s not. He’s actually with EOS GmbH (eos.info), where his job is “business development.” For the auto industry. And yes, EOS is a company that produces laser sintering systems, systems that can make parts in metal. These parts aren’t necessarily prototypes. Some of them are used in end products. Like the door hinges being produced on EOSINT machines for use on the Airbus 380. (Zaepernick explains that compared to a hinge made with conventional methods, the sintered part is designed so that there are weight savings with no loss in functional performance.)
Given that during the last 10 years there have been fewer than 100 A380s produced, and given that in a typical auto assembly plant, that’s the level of production in under two hours, this seems as though it is good for airplanes and not particularly relevant to cars. And while Zaepernick acknowledges that “the challenge is achieving the high volume, low cost, high quality of automotive,” there is a more immediate, more practical application of the sintering technology: Producing parts for low-volume cars, be they luxury or performance models.
Now, he suggests, that volumes up to 5,000 parts are feasible (taking into account factors ranging from time to cost). In 10 years he thinks that number will grow 10-fold. But in the meantime, there is the potential of mass customization through the process.
What’s more, there is the possibility of producing components in a way that isn’t being done today (“What if there were no manufacturing constraints?”), such as a gearbox case that is produced with a lattice structure, a case that is light, strong and materials efficient . . .
Honda R&D, where the engineering is done for products and process, is known to be a place where they run lean and efficiently. Allen Kreemer worked at Honda R&D in Raymond, OH, for seven years. When he worked there, he was working with the FDM—fused deposition modeling—equipment that they had in the facility. They were using the equipment to crate trim panels and front and rear fascias. To produce prototype tooling with sweeps and extruded shapes that are not possible to achieve with CNC machining.
Kreemer recalls a time when they’d produced door handles for an evaluation vehicle. When the evaluators came in, there
was some consternation. The door handles looked and felt so authentic that they thought that Kreemer and his colleagues had bought the tooling needed to produce the parts, that they didn’t produce it with thermoplastic with the FDM process.
Now Kreemer is the DDM Vertical Market Technology Leader-Automotive, for the company that produces the FDM machines, Stratasys (stratasys.com).
And when Kreemer leaves the Frankfurt Messe, he’s planning to visit with people in the auto industry about the potential of the technology, not just for making things like components for concept cars and evaluation vehicles, but for customized production vehicles.
“Customized” not just in the context of modified fascias and trim pieces. “We can build a custom interior for a person,” he says. When people are paying a considerable amount of money for “bespoke” vehicles—and people are paying this, not many, but in this case volume isn’t what matters—he suggests that it is a fairly straightforward manner to laser scan them then use the digital information to create an interior that is specifically modeled for their physiology.
This is not the future. This is now.
Printed in metal. Imagine the challenges of trying to make that with casting and machining. Far more difficult than downloading an STL file of the part and then pressing “Start.”
Check out amerimold 2012, which will be held June 13-14 at the Suburban Collection Showcase in Novi, MI. It promises to be a veritable showcase of advanced technology and services for those who are looking to accelerate their product development. More info: amerimoldexpo.com
A desktop 3D printer that’s claimed to be three times faster than any other machines in its class and the ability to build parts with feature sizes as small as 0.010 in. and wall thicknesses as thin as 0.025 in. is now offered by 3D Systems (3dsystems.com). The ProJet 1000, which has a work envelope of 6.75 x 8 x 7 in., prints ivory-colored, snap-fit plastic parts at speeds up to 0.5 in/hr. Price point: $10,900.
One limitation of selective laser melting (SLM), a process that uses a high-powered laser to fuse thin layers of metal powder into fully dense parts, is that it requires support structures, or “anchors,” be added to the part as it’s built. These anchors help prevent warping (e.g., if there are overhangs in the part design, as the material hardens there is a tendency for the part to warp upward), but limit part complexity and increase cost (because the anchors have to be removed from the finished part). However, an anchorless SLM-based process (ASLM) able to build complex parts has been developed by researchers at the UK-based University of Sheffield (sheffield.ac.uk).
“Presently, we believe that around 50% of parts that designers would like to make by SLM cannot be made or are too expensive to make because of the need for anchors,” says lead researcher Neil Hopkinson. “ASLM should enable most, if not all, of these currently impossible or uneconomic geometries to be made.”
ASLM involves melting dissimilar materials to form a eutectic system alloy. Eutectic alloys harden at a single temperature, which reduces the traditional stresses as parts are built, eliminating the need for anchors. Currently, ASLM has succeeded in building complex parts using low melt temperature metals, such as bismuth and zinc. The next step is building parts with high melt temperature metals, like aluminum. Hopkinson hopes ASLM can be commercialized within the next two years.
A high-temperature, dimensionally stable material capable of simulating the thermal performance of engineering plastics, RGD525, is now offered by Objet Geometries (objet.com). Parts printed with it will maintain shape and resist warping at temperatures below 65º C prior to curing or 80º C or above after curing, and as long as pressures are below 0.45 MPa.
RGD525 is presently available for use with Objet’s Connex500 multi-material 3D printer, where it can be used with the company’s Tango family of rubber-like materials to simulate overmolding on printed parts. It can also be used with the company’s Eden500V single-head, high-resolution printer.
Looking for a desktop machine that can quickly mill prototype parts within an 86 x 55 x 26-mm work envelope? Check the iModela iM-01 from Roland DG (rolanddg.com). It has a 214 x 200 x 205-mm footprint (a.k.a., 8.4 x 7.9 x 8 in.) and weighs just 3.7 lb. It mills parts out of a combined wax, foam, balsa wood and plastic material with a spindle that can accommodate tools up to 2.35-mm in diameter. And it’s affordable, with a price tag of $1,000.