Over the last ten years, 3D printing has risen from an expensive and relatively obscure manufacturing method to a mainstay in the Arts, Science, Technology, Medical, and Engineering Fields. The many benefits of 3D printing are utilized by researchers, manufacturers and hobbyists alike: fast prototyping and turnaround time, ease of use, affordability, and accessibility. The uses for 3D printing are endless; the manufacturing technique is used to make medical implants and prosthetics more customized and affordable, replacement parts accessible, and the imagination realizable. People have created prosthetics, solar cells, organs, bicycles, furniture, guitars, food and much more.

In most cases, the use of 3D printing, an additive manufacturing process, creates a net reduction of waste; typical manufacturing currently has a scrap (waste) rate saturated at 21%among professionals. Our experience with learners new to 3D printing is much higher, estimated at 60%. The continued increase in utilization of 3D printing has the potential to reduce the scrap rate to roughly 10% in the next 25 years. Furthermore, the waste produced from PLA 3D printers is free from contaminants and is considered biodegradable. Alongside these benefits, local or on-site 3D printing such as can be found at universities, community makerspaces, or even inside homes reduces packaging and fuel consumption from product shipment.

Unfortunately, as the popularity of 3D printers increases and as the printing material becomes more affordable and accessible, there is the potential for a net increase in total waste. Waste from 3D printing is created in two primary ways. Structures, such as supports and rafts, are printed alongside the model to prevent deformation. These are then removed from the print and thrown away. The second way is through failed prototypes and design mistakes. During any development process, project success is a result of optimization and learning from errors – usually in 3D printing the entire model is scrapped in favor of the newer version. Students, technicians, and hobbyists are developing and iterating prototypes much more quickly as a result of this technology. Even in the best case scenario, if we combine the 10% scrap rate with the growing popularity of 3D printing (20.6% per year based on market value) we see that action in this area is needed in order for the University of California to hit the zero waste mark by 2020.

So what exactly is being thrown away? The answer is: Plastic. The two most commonly used plastics in 3D printing are polylactic acid (PLA) and acrylonitrile butadiene styrene (ABS). Some may object here, “aren’t those already recyclable? I heard you can even compost PLA.” While this is technically true there are some important caveats:

• PLA is derived from biomass (often sugarcane or corn starch) and is biodegradable. However, special conditions are necessary to biodegrade this material effectively; industrial composting can decompose PLA within 3 months. Compare this with 100 – 1000 years it would take in a landfill. Although these facilities exist in California, waste from 3D printing often does not end up in one, due to the lack of education and logistical impediments.
• ABS is derived from petroleum and does not biodegrade. It is, however, recyclable. Unfortunately, you often find a trash bin next to 3D printers, not recycling bins.