16-Year-Old Builds Machine That Turns 3D-Print Waste Back Into Filament

A 16-year-old Massachusetts student has built a desktop machine capable of turning discarded 3D-printing plastic back into reusable filament. Benjamin Davis, a student at Bishop Feehan High School, developed the system to address the scraps, failed prints and leftover plastic that regularly accumulate around additive manufacturing.

Davis’ design combines two plastic-processing techniques — pultrusion and extrusion — into a single recycling system. According to the Society for Science, combining the two approaches made the process around 45% more efficient than using them separately. The resulting machine is designed to produce higher-quality recycled filament while remaining simple enough for nontechnical users to operate.

Cost is another important part of the project. The Society for Science says Davis’ design costs around 90% less than commercial recycling alternatives, potentially making small-scale plastic recycling more accessible to schools, makerspaces and individual 3D-printer users. The problem itself is significant: as much as 67% of filament used in a typical 3D-printing project may eventually become waste.

Building the machine took considerably more than one successful prototype. Davis reportedly spent more than 800 hours developing the system, went through over 50 component iterations and completed several major redesigns before reaching the version presented at the Regeneron International Science and Engineering Fair.

The work earned Davis a $75,000 Regeneron Young Scientist Award at ISEF 2025, where he was one of the competition’s top winners. Since then, he has continued developing the technology and has said he plans to make the extrusion-pultrusion system more efficient and commercially viable. The larger promise is straightforward: instead of treating failed 3D prints as unavoidable waste, recycling could happen directly beside the machines producing it.