The world of 3D printing has a complicated relationship to sustainability. It’s difficult for both industry and consumers to precisely identify if and how 3D printing can contribute to a more sustainable world, specifically within the manufacturing industry.
To try clearing the smoke a bit, so to speak, let’s take a look at two common misconceptions about 3D printing as it relates to sustainability.
3D Printing will reduce transportation costs by shifting manufacturing leverage to localized factories or consumers’ homes.
At the surface, this idea seems plausible: if manufacturers or makers can ship one product to themselves and manufacture exclusively with that product (i.e. a 3D printer), shouldn’t that prevent some of the negative environmental costs of shipping dozens of individual parts?
The fallacy in this line of thinking lies in the limited capabilities of 3D printing. The vast, vast majority of consumer-grade products are made of multiple materials in multiple forms, very few of which 3D printing can realistically produce. A manufacturing operation or a maker that utilizes 3D printing would therefore have to ship all non-printable parts in addition to the printer and print material.
This allows for a few special cases where additive manufacturing would still reduce transportation costs, such as the production of many objects from just one material with a 3D printer or a hobbyist/maker committing to use fully 3D printed objects instead of shipping many non-printed objects.
In any case, this misconception hides the fact that 3D printing’s largest environmental impact is energy consumption. While reducing transport costs with one of the specific operations described above would be productive, it ultimately may take focus away from reducing energy consumption.
Since it’s an additive rather than subtractive manufacturing method, 3D printing automatically reduces waste production.
To be clear, 3D printing does have great potential to reduce waste, but this outcome must be pursued intentionally.
Some 3D printing processes, such as FDM/FFF printing, can produce a print that’s a mere fraction of a percent waste byproduct. Consider any print that lies flat on the print surface, has no steep overhangs, and utilizes a low-warp material like PLA: the only waste from this print would be a skirt or brim or a failed print. Other 3D printing processes, though, produce prints with much greater waste percentages. On the industrial side of things, Polyjet printers waste a minimum of 43% of its liquid polymer (more if the model requires supports); unused metal powder from metal sintering processes deteriorates, leading to 20% unused metal powder loss per print.
For makers, high-waste prints include models requiring lots of support material, failed prints due to careless tuning or slicing, and non-functional models that never actually get used.
With efficient design, mindful printing, and careful preparation, makers and industrial manufacturers can indeed reduce waste production, but they must do so with intention and forethought.