Green fab lab applications of large-area waste polymer-based additive manufacturing

Abstract

Fab labs, which offer small-scale distributed digital fabrication, are forming a Green Fab Lab Network, which embraces concepts of an open source symbiotic economy and circular economy patterns. With the use of industrial 3D printers capable of fused particle fabrication/ fused granular fabrication (FPF/FGF) printing directly from waste plastic streams, green fab labs could act as defacto recycling centers for converting waste plastics into valuable products for their communities. Clear financial drivers for this process have not been studied in the past. Thus, in this study the Gigabot X, an open source industrial 3D printer, which has been shown to be amenable to a wide array of recyclables for FPF/FGF 3D printing, is used to evaluate this economic potential. An economic life cycle analysis of the technology is completed comprised of three cases studies using FPF for large sporting equipment products. Sensitivities are run on the electricity costs for operation, materials costs from various feed stocks and the capacity factors of the 3D printers. The results showed that FPF/FGF 3D printing is capable of energy efficient production of a wide range of large high-value sporting goods products. In all cases, a substantial economic savings was observed when comparing the materials and energy related costs to commercial goods (even for customized goods). Using locally-sourced shredded plastic represented not only the best environmental option, but also the most economic. For the case study products analyzed even the lowest capacity factor (starting only one print per week) represented a profit when comparing to high-end value products. For some products the profit potential and return on investment was substantial (e.g. over 1000%) for high capacity use of a Gigabot X. The results clearly show that open source industrial FPF/FGF 3D printers have significant economic potential when used as a distributed recycling/manufacturing system using recyclable feed stocks in the green fab lab context.

3-D Printable Polymer Pelletizer Chopper for Fused Granular Fabrication-Based Additive Manufacturing

“…Fused granular fabrication (FGF) or the more generic fused particle fabrication (FPF) (indicating any size or shape of polymer feedstock) have been developed and designs are flourishing in maker communities [19][20][21] as well as in industry with commercialized printers [21][22][23][24][25][26]. Academia has also taken a keen interest in the technology [27,28] for virgin [29] and recycled materials [30,31] including multi-head [32], industrial robot adaptations [33], electronics printing [34], flexible materials printing [35], and biopolymer printing [36]. To date, however, only a small subset of the thermoplastic materials capable of being printed by such systems have been investigated.…”

Open Source Waste Plastic Granulator

“…The particle sizes demonstrated in Figure 10 are small enough to use in a wide array of recyclebots (both commercial and homemade) as well as for direct printing via FPF/FGF as demonstrated in references [58][59][60].…”

“…Figure 10 shows the resultant particles and particle size distribution, where it is clear that the majority of particles are fines with total areas under 10 mm 2 . These particle sizes are appropriate for the majority of recyclebots as well as direct material extruder-based 3D printers such as the Gigabot X [58][59][60]. Using the initial acoustic measurements, an expansion chamber was designed ( Figure 9) that could be attached to the five-gallon bucket shop vacuum, and a 3D model was produced to utilize PVC and a 3D printable components to reduce noise from the operation of the device.…”

“…The volumes that the device can process are appropriate for small businesses [13], community centers, libraries, maker spaces, and fab labs [59,66] that could potentially become community distributed recycling centers. There are challenges with this approach throughout the world.…”

“…These fused particle fabrication (FPF) or fused granular fabrication (FGF) 3D printers are becoming established in the academic [49][50][51][52][53][54], maker [55][56][57], and commercial venues (e.g., GigabotX, PartDaddy, Cheetah Pro, David, Erecto-Struder, etc.). FPF/FGF printing is possible with recycled materials [58][59][60], as is using FGF printing of molds for distributed injection molding of larger replicate products [60].…”