3D printing is full of innovations made by small firms who’ve tweaked the same basic ideas just a little bit, but come up with radically different outcomes. Collider, a small startup based in Chattanooga TN, is producing a DLP resin printer that prints hollow molds and then fills them.
That’s really all there is to it. The Orchid machine prints a thin shell using a photocuring resin, and uses this shell as the mold for various two-part thermoset materials: think epoxies, urethanes, and silicones. The part cures and the shell is dissolved away, leaving a solid molded part with the material properties that you chose.
This is a great idea for a couple of reasons. DLP-based resin printers can have very fine features, but they’re slow as dirt when a lot of surface area needs to be cured. By making thin-walled molds, this stage can go faster. The types of UV-curing resins out there for use in resin printers is limited by the need to photo-cure, while the spectrum of two-part plastic materials is much broader. Finally, resin printers are great for printing single topologically-simple objects, and molds are essentially just vases.
While we’re sure that there’s a market for these kind of machines in small-scale manufacturing, this is also an eminently DIY procedure. We’ve personally even made some hollow 3D parts and filled them with epoxy to strengthen them up, but never taken the last conceptual leap to thinking of the 3D-printed part as a disposable one-off mold. We’ve even cast chocolate in 3D-printed molds, with varying degrees of success. We’ve also seen great things done in lost-PLA casting. 3D printing and mold-making are made for each other. Building a single machine to run all of the steps, and taking care of the messy details, is a neat idea.
[via Engineering.com] and thanks to [RandyKC] for the tip!