Title: FABRICATION OF A LOW-COST PELLET FED 3D-PRINTER

Authors: Jason Trafas, Kevin Hjelstrom, Evan Impink, Eli Gallo, Kai Van Hoy, Nicole Hoekstra

DOI: 10.33599/nasampe/s.23.0228

Abstract: An extrusion-based pellet printer overcomes inherent challenges with alternative technologies. For thermoplastics, filament-based printers require custom formulations extruded into in-spec filament. Direct Ink Writing printers have limited build volumes for thermoset-based compounds. Selective Laser Sintering limits users to powdered feedstock. Pellet printers allow research teams the ability to print thermoplastic specimens and prototypes without the additional challenge of manufacturing in-spec filament or powders. A modified 3D printer which can print thermoplastic / thermosetting polymer blends would enable research teams to select from a much broader range of materials for use with additive manufacturing. 3D printing with pellets is physically and financially advantageous over FDM printing. During filament production, polymer chains experience additional shear and heat degradation. In addition, misprints could easily be turned back into pellets and reprinted without producing filament, tightening the closed-loop supply chain. A LulzBot TAZ 5 3D printer was modified at Western Washington University to allow for printing directly from thermoplastic pellets. The printer utilizes a cooled hopper and feed section, heated barrel, rotating screw, as well as a custom post-processing step that is compatible with the slicing application CURA. The printer is designed with a modular platform that allows for future modifications to enable post curing of thermoset formulations. To date, high impact Polystyrene has been printed into low quality, simple shapes. Design modifications are planned to reduce heat transfer to the feed section.

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Conference: SAMPE 2023

Publication Date: 2023/04/17

SKU: TP23-0000000228

Pages: 12

Price: $24.00