Design and Development of a Modular 3D-Printed Extruder for Recycled PET Filament Production

Abstract

This paper presents the design, fabrication, and functional validation of a low-cost, modular extruder system capable of converting manually cut PET-bottle strips into 3D-printing filament. The extruder is composed of 3D-printed structural elements, a metal heating barrel, a digital thermostat with an ON/OFF control, and a direct-drive 12 V DC motor for material feeding. The heating profile was stabilized at 230 °C to ensure proper melting and extrusion. The resulting system successfully  produced filament of consistent diameter, suitable for non-loadbearing applications. This work demonstrates the feasibility of decentralized, smallscale PET recycling using accessible components and open-source design principles, contributing to circular-economy practices in the context of Fused Deposition Modeling (FDM).