In a presentation at Virtual Engineering Days, Joe Cretella, applications engineering manager at ProtoLabs, offered technical examples about how multijet fusion (MJF) can best be used, while Brent Ewald, solutions architect from HP, talked about developing strategies for using MJF and encouraged companies to think about how the technology can complement their more traditional manufacturing efforts.
Cretella began by noting that the ideal applications for multijet fusion can include prototypes and end-use parts; complex geometries requiring hinging or light weighting, high strength, and temperature resistance; jigs and fixtures, brackets, clips; and component housings.
He cited a recent case study that ProtoLabs did with a university in France and its German counterparts to produce reusable face shield. Cretella said they were able to optimize the design so that it could be printed as a single component. “So it could fit a large number of those face shields into a single build,” he explained. “And that's really going to be key on thinking about designs, especially as we're getting into talking about the parts, we want to be able to fit a high volume.”
Moving parts into a single build will maximize efficiency, reduce costs, and reduce overall time, he said, especially when compared with injection molding and the time needed to generate tooling and scale up.
Multijet fusion uses Nylon material PA 12 black and PA 12 40% glass-filled black, Cretella said. The 40% glass-filled gives a little bit better mechanical properties in terms of being stiffer and also increases the heat deflection temperature of the material itself, he said.
MJF will have a smaller minimum feature size, as compared with SLS, he said, and it is also good for slots and channels. He encouraged manufacturers to follow traditional injection molding principles of having universal, uniform wall thicknesses.
Cretella finished his portion by inviting viewers to submit their geometries to ProtoLabs for a quote. “We've seen a lot of different parts,” he said. “We have a lot of experience and can create a solution that could get you a part that's going to be really beneficial.”
Ewald pivoted the discussion to some scenarios where it might make sense to incorporate multijet fusion into manufacturing processes. He spoke of using additive manufacturing as bridge production to meet time-to-market goals. “Lost time to market will end ultimately lead to lost sales,” he said. “So, when we talk about using additive manufacturing to stay on schedule, it doesn’t even have to accelerate the schedule, but just to stay on until you have a stable design that will enable you to start production early and then change over to a lower-cost traditional tool later on,” he said.
He also spoke of bridge manufacturing for times of uncertainty. “Uncertainty comes in many flavors,” he said. “It could be that it's financial uncertainty. You don't want to spend the money on the tooling this quarter and you want to wait, there's some decision that you trigger there and additive manufacturing offers a great delay here.”
Another uncertainty he mentioned could be an unstable forecast. “You're launching a fairly new product, and you don't know what the demand will be,” Ewald explained, noting that delaying investing in tooling can be an advantage.
Ewald stressed that he doesn’t consider 3D printing to be competitive with injection molding or traditional processes; rather, it is complementary. “There are things it can fundamentally do that others can't, and that other technologies can,” he said. “By integrating it into the product life cycle, you can get better results. Through utilizing hybrid push-pull, supply chain, and other sort of other strategies, you can create a package that makes sense to integrate into your production,” he concluded.
"Tips and Tricks to Leverage Multi Jet Fusion in Your Product Development Cycle" was held June 15 and is available on demand for 30 days.