Engineering news
Engineers at Massachusetts Institute of Technology (MIT) created the desktop printer, which they say cuts the standard printing time for “a few Lego-sized bricks” from one hour to a few minutes.
The printer uses two speed-enhancing components: a screw mechanism which feeds polymer through the printing nozzle at a higher force than standard “pinch wheel” feeders; and an in-built, high-temperature laser which rapidly heats and melts the material, allowing it to flow quickly.
The technique could make 3D printing a more viable production technique, said MIT mechanical engineer Anastasios John Hart.
“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,” he said. “If I'm a repair technician and I could have a fast 3D printer in my vehicle, I could 3D print a repair part on-demand after I figure out what's broken. I don't have to go to a warehouse.”
Emergency medicine and 3D printing objects in remote locations could be other applicable fields, said Hart.
Printing 10 times faster would also be a “massive benefit” in educating the engineers of the future, said Simon Biggs from engineering firm Renishaw to Professional Engineering. The education outreach officer runs 3D printing workshops for children aged 10-16, transforming designs from sketches into physical objects. The technology’s accessibility can encourage them to try careers in engineering or other STEM subjects, said Biggs.
However, technical limits do exist. “One of the downsides at the moment is obviously the build time,” he said. “Teachers tend to stay away from it slightly because it’s taking so long to build something… it could be eight hours to print a student’s prototype project. If you can reduce that time with a new 3D printer, that’s going to benefit every teacher, every classroom. It’s definitely a step in the right direction.”
The new printer’s advances also create other potential issues, said the MIT engineers: it is so fast that previous layers do not always melt before the next layer starts to go down.
“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,” said 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.”
As well as tackling the cooling issue, the team also hopes to apply the technique to more advanced materials such as high-strength polymers, and to use the new design for larger-scale printing.
The MIT work was published in Additive Manufacturing.
Content published by Professional Engineering does not necessarily reflect the views of the Institution of Mechanical Engineers.