Five myths about 3-D printing

Richard A. D’Aveniis the Bakala professor of strategy at Dartmouth’s Tuck School of Business. He is the author of the forthcoming book “The Pan-Industrial Revolution: How New Manufacturing Titans Will Transform the World.”

Like any fast-developing technology, 3-D printing, described more technically as "additive manufacturing," is susceptible to a variety of misconceptions. While recent debates have revolved around 3-D-printed firearms, most of the practical issues in the field come down to the emergence of new manufacturing techniques. The resulting culture of innovation has led to some persistent myths. Here are five of the most common.

Myth No. 1: 3-D printing is slow and expensive

Early 3-D printing was indeed agonizingly slow, requiring expensive equipment, pricey materials and tedious trial-and-error fiddling to make improvements. In 2015, Quartz magazine said that 3-D printers are "still slow, inaccurate and generally only print one material at a time. And that's not going to change any time soon." When the stock price of the leading printer manufacturers was free-falling in 2016, Inc. magazine announced that 3-D printing was "dying," mostly because people were realizing the high cost of printer feedstock.

But a variety of new techniques for additive manufacturing are proving those premises wrong. Desktop Metal's Single Pass Jetting, HP's Multi Jet Fusion and Carbon's Digital Light Synthesis can all make products in minutes, not hours. Lab tests show that these printers are cost-competitive with conventional manufacturing in the tens or even hundreds of thousands of units. Many of the newest printers also use lower-price commodity materials rather than specially formulated proprietary feedstocks, so the cost is falling rapidly.

Myth No. 2: 3-D printers are limited to small products.

By design, 3-D printers are not large. They need an airtight build chamber to function, so most are sized no larger than a copy machine. Nick Allen, an early 3-D printing evangelist, once said, "Producing anything in bulk that is bigger than your fist seems to be a waste of time." TechRepublic warned in 2014 that 3-D printing from "plastic filament can't make anything too sturdy," which would further limit the size of printed objects.

But some techniques, such as Big Area Additive Manufacturing, work in the open air and can generate highly resilient pieces. They've been used to build products from automobiles to jet fighters. A new method for building involves a roving "printer bot" that gradually adds fast-hardening materials to carry out the construction. This spring, a Dutch company completed a pedestrian bridge using 3-D printing methods.

Myth No. 3: 3-D printers only produce low quality products.

As anyone who's handled a crude 3-D-printed keychain can probably guess, the hardest part of 3-D printing is ensuring that a product looks good. When you print layer upon layer, you don't get the nice smooth finish of conventional manufacturing. "There's no device that you're using today that can be 3-D printed to the standard you're going to accept as the consumer," said Liam Casey, the chief executive of PCH International, back in 2015. The Additive Manufacturing and 3D Printing Research Group at the University of Nottinghamin Britain likewise predicted that high post-printing costs, among other challenges, would help keep 3-D printing from expanding much beyond customized or highly complex parts.

But some new additive techniques, such as Digital Light Synthesis, can generate a high-quality finish from the start. That's because they aren't based on layering. The products are monolithic - they emerge smoothly from a vat of liquid, similar to the reassembled robot in the Terminator movies. Other printer manufacturers are building automated hybrid systems that combine 3-D-printed products with conventional finishing, so you get most of the benefits of additive with only a bit more cost.

If we think of quality more broadly, additive is likely to improve on conventional products. That's because 3-D printing can handle sophisticated internal structures and radical geometries that would be impossible via conventional manufacturing. Boeing is now installing additive support struts in its jets. These struts are a good deal lighter than conventional equivalents, but they're stronger because they have honeycomb structures that couldn't be made before. Adidas is making running shoes with complex lattices that are firmer and better at shock absorption than conventional shoes.

Myth No. 4: 3-D printing will give us artificial organs.

One of the most exciting areas of additive manufacturing is bioprinting. Thousands of people die every year waiting for replacement hearts, kidneys and other organs; if we could generate artificial organs, we could eliminate a leading cause of death in the United States. We've already made major advances with customized 3-D-printed prosthetics and orthodontics, and most hearing aids now come from additive manufacturing. Why not organs? A 2014 CNN article predicted that 3-D-printed organs might soon be a reality, since the machines' "precise process can reproduce vascular systems required to make organs viable." Smithsonian magazine likewise announced in 2015 that "Soon, Your Doctor Could Print a Human Organ on Demand."

But scientists have yet to crack the fundamental problem of creating life. We can build a matrix that will support living tissue, and we can add a kind of "cell ink" from the recipient's stem cells to create the tissue. But we haven't been able to generate a microscopic capillary network to feed oxygen to this tissue.

The most promising current work focuses on artificial skin, which is of special interest to cosmetic companies looking for an unlimited supply of skin for testing new products. Skin is the easiest organ to manufacture because it's relatively stable, but success is several years away at best. Other organs are decades away from reality: Even if we could solve the capillary problem, the cost of each organ might be prohibitive.

Myth No. 5: Small-scale users will dominate 3-D printing.

In his best-selling 2012 book, "Makers: The New Industrial Revolution," Chris Anderson argued that 3-D printing would usher in a decentralized economy of people generating small quantities of products for local use from printers at home or in community workshops. The 2017 volume "Designing Reality: How to Survive and Thrive in the Third Digital Revolution" similarly portrays a future of self-sufficient cities supplied by community "fab labs."

In reality, relatively few individuals have bought 3-D printers. Corporations and educational institutions have purchased the majority of them, and that trend is unlikely to change. Over time, 3-D printing may bring about the opposite of Anderson's vision: a world where corporate manufacturers, not ordinary civilians, are empowered by the technology. With 3-D printing, companies can make a specialized product one month, then switch to a different kind of product the next if demand falls. Such changes would be costly and time-consuming with conventional techniques, but 3-D printing makes manufacturing far more flexible. General Electric's factory in Pune, India, for example, can adjust its output of parts for medical equipment or turbines depending on demand.

As a result, companies will be able to profit from operating in multiple industries. If demand in one industry slows, the firm can shift the unused factory capacity over to making products for higher-demand industries. Eventually, we’re likely to see a new wave of diversification, leading to pan-industrial behemoths that could cover much of the manufacturing economy.