This month we have tested a variety of printing materials with the GBX, including recycled PET pellets, grocery store bags, plastic Starbucks cups, and polycarbonate manufacturing waste. And our in-house failed prints and supports? Instead of going into the trash, we’re granulating them into PETG, PLA, and polycarbonate regrind for GBX printing.
A big hurdle for printing with regrind is identifying particle characteristics– size, sphericity, etc– for optimal printing. Using the open source software ImageJ, we’ve determined the ideal particle size to be around 3mm in length, but further testing still needs to be done. For more information on the particle analysis and feed tests, check out our forum posts: ImageJ Particle Analysis and ImageJ Circularity Analysis and Feed Tests