Rapid manufacturing proponent 3D Systems (3DS; Rock Hill, SC) has made the broad claim that its stereolithography (SLA) and selective laser sintering (SLS) 3D manufacturing printers can match the productivity of traditional injection molding in the direct manufacture of functional parts.
To prove its point, the company released a video on Youtube showing production of mini lamp shades at the rate of 2400 for 20 hours, translating to 30 seconds per part. 3DS says it is debuting a series of videos that demonstrate how its fab-grade printers can manufacture thousands of parts at speeds comparable to traditional injection molding operations. The first one features what appears to be the skeptical boss of an injection molding firm visiting 3DS' headquarters to break the news that injection molding productivity will never be surpassed by 3D printing.
|Has 3D printing matched and even surpassed injection molding cycle times?|
|Mini lamp shades: 2400 manufactured in 20 hours.|
The molding shop boss is converted by the time he leaves the 3DS headquarters, saying: "3D printing is that fast. It's a fact!"
According to 3DS, "this breakthrough opens up the possibility of just-in-time, high volume, flexible additive manufacturing using the company's precision enabling manufacturers to produce functional, precision parts in seconds, without the need for tooling or a lengthy supply chain." The company adds: "Today's announced production speed records are shifting the manufacturing paradigm again: from low volume production to high volume direct manufacturing of complex parts across a range of use cases and industries."
"Our unwavering commitment to customer success through innovation has literally broken the mold this time - challenging the myth that 3D printing can't match the productivity of injection molding," said Cathy Lewis, 3DS' CMO. "This is just the beginning. We are working on additional applications that defy traditional manufacturing constraints, allowing our customers to go from idea to product in hours, instead of months - to truly manufacture the future."
Unsurprisingly, injection molding machine suppliers are somewhat at odds with 3Ds' claim. Admittedly it might make sense for 3D printing if a limited run of 2,000 parts was needed in double-quick time because a tool wouldn't have to be built. But if one is talking of hundreds of thousands of widgets, they say injection molding machines retain the upper hand. "Such mini-lamp shades could be molded in a 16–32-cavity tool in a cycle time of 20 seconds," notes machine builder Engel, "or less than 1.25 s per part). Engel also questioned the mechanical integrity of 3D-printed parts versus those injection-molded at pressures of the order of 1000 psi.
And then there's the question of machine cost. A high-performance injection molding machine is probably still a lot cheaper than an industrial-scale 3D printer. Further, many more materials are currently injection-moldable.
Engel feels that 3D manufacturing will first make its mark in the metal market, where laser-sintered parts will compete successfully with machines metal parts. But make no mistake: While 3DS' latest assertion might be a bit hyped, 3D printing is here to stay. And it will continue to make rapid advances to the point where it will compete more widely with injection molding and other processes. Just don't expect the mature, versatile, productive and cost-effective injection molding machine to disappear from the shop floor any time this century; perhaps even longer.