Despite the 3D printing revolution shaking up the design and manufacturing industries, one thing has been holding it back from fully infiltrating more commercial day-to-day situations – it's slow. Most desktop printers take well over an hour to generate a small object, but a new design from engineers at MIT could completely change the 3D printing game, performing up to 10 times faster than currently available devices and printing complete objects in just minutes.
Associate professor of mechanical engineering at MIT, Anastasios John Hart, and former graduate researcher Jamison Go, focused on three fundamental factors that limited the speed of a conventional desktop extrusion 3D printer: the speed a printhead can be moved, the force pushing the printing material through the nozzle, and the rate the material can be melted to make it flow.
"Given our understanding of what limits those three variables, we asked how do we design a new printer ourselves that can improve all three in one system," says Hart. "And now we've built it, and it works quite well."
The team ultimately redesigned several mechanisms in and around the printhead and also added a laser to melt the plastic filament more rapidly before it passes through the nozzle. The resulting system, which they dubbed "FastFFF" (fast fused filament fabrication), was up to 10 times faster than comparable commercially available printers, taking just minutes to print objects that previously would have taken up to an hour with a conventional 3D printer.
According to the researchers, their prototype FastFFF system boasted a volumetric build rate of 127 cm3/hr, which they say is around seven times greater than commercial desktop FFF systems producing objects of a comparable resolution. However, at its maximum extrusion rate the printhead would be able to produce objects at 282 cm3/hr, which would be around 14 times greater than the team's benchmarks.
But one design challenge still looms over the engineering team before the design can be deemed completely successful. Upping the speed of the printing process meant that there wasn't enough time for each layer to entirely firm up before a subsequent layer was printed.
"We found that when you finish one layer and go back to begin the next layer, the previous layer is still a little too hot," says Hart. "So we have to cool the part actively as it prints, to retain the shape of the part so it doesn't get distorted or soften."
The team is confident that challenge can be resolved, with the implications of speeding up the 3D printing process potentially resulting in some revolutionary outcomes for several industries. Emergency medicine, for example, could 3D print prosthetics in minutes while surgical procedures are taking place.
"If I can get a prototype part, maybe a bracket or a gear, in five to 10 minutes rather than an hour, or a bigger part over my lunch break rather than the next day, I can engineer, build, and test faster," adds Hart. "If I'm a repair technician and I could have a fast 3-D printer in my vehicle, I could 3-D-print a repair part on-demand after I figure out what's broken. I don't have to go to a warehouse and take it out of inventory."
Take a look at the printer in action in the video below.
The new innovation was reported in the journal Additive Manufacturing.
Source: MIT via Eurekalert
Good luck printing automotive parts in PLA and expecting them to function!