UNIVERSITY PARK, Pa. —  It’s an old idea, really. One of the oldest.

To make useful things, humans remove the bits that aren’t part of the thing we want. We've learned how to then make giant factory machines that assemble the different parts into a more complex whole. It’s called “reductive” manufacturing — with some assembly required — and has dominated our lives for thousands of years.

From chipping flint arrowheads millennia ago to carving wooden tools, to assembling chairs or tables from Ikea, to Michelangelo saying his job was to whack away waste marble, from a shapeless block, anything that didn’t look like an angel; to drilling and molding and stamping and extruding and assembling parts for rocket engines and patio furniture and giant oil tankers — we make things, by the billions, mostly through variations of reductive manufacturing processes. And, we’ve gotten very, very good at it.

But that approach is changing, and with it our future.

“3-D printing” — the colloquial name for “additive manufacturing” — is a technology that theoretically enables us to make almost anything by building it up rather than cutting something away.

Food. Guns. Toothbrushes. Shoes. Art. Clothing. Jewelry. Building materials. Electronic devices. Car dashboards. Moon habitats. Office buildings. Transplantable human organs and living tissue for medical research.

Penn State faculty and a growing group of students are fully engaged in research and practical experiments in this new world, and these programs are gaining attention and enrollments.

3-D printing as a reality has been around for a decade or more. With this technique, objects are built up in layers — sometimes only microns thick — in three dimensions. The technology has been used mostly to make models in architecture, car designs and other fields. In the past couple of years, however, boosted by the rocket fuel of the Internet and a culture of collaboration and Open Source communities, and breathtaking advances in software and computing power, it is starting to hit the mainstream. And it is sparking innovation through advances in computer aided design (CAD) software and the Internet as it links researchers, tinkerers and entrepreneurs together.

It may reduce fossil fuel use by requiring less raw material and shorter supply lines, and can create completely new designed objects that cannot be made with old methods. The ripples of change on a global scale will ride faster development of new designs, less dependence on fossil fuels for transportation and faster retooling or increased customization.

3-D printing studies at Penn State

Richard Devon, professor of engineering design in Penn State’s College of Engineering, and recent doctorate recipient and instructor David Saint John are guiding a growing number of engineering students to build printers to learn the technology from the inside out. They’ve built and shared printers with Mark Shriver in the Department of Anthropology, and he has used it to scan and “print” faces. Another is in the hands of the Department of Material Sciences and Engineering, and another is slated to go to the architecture school. Work with 3-D printing to fabricate models and practical-use objects is happening across the University, including the Penn State Lunar Lion project and the Applied Research Laboratory.

“Something possessed me to purchase a kit with my own money — perhaps it was a degree of frustration at what it would take to use actual funds to do so at the time,” Saint John explained. “When I got my kit running, Richard was willing to post a course where we built our own printers, which I had the opportunity to run. We’ve added content and course expectations as we went.  

“That first section was in spring of 2011 — we had 11 students, met once per week and worked on three kits. The second semester had something like 24 students, and we built four units. The third semester involved the construction of three kits and the beginning of our print service, where we offer to print prototypes for other students,” he continued.  

“By the fall semester of 2012, we had two sections and 42 students. We built four printers and explored a variety of other aspects to the subject, as well as introducing a blog component to the course.” During the spring 2013 semester, Saint John noted, they had 23 students and worked on six new machines, for a total of about a dozen systems, after delivering one to the materials science and engineering department, to print pastes as well as polymers, and to Penn State Brandywine.

According to Michael Policelli, graduate student in aerospace engineering and chief technologist for the Penn State Lunar Lion X Prize Team, “As the technology’s use and acceptance within the aerospace community grows, additive manufacturing will be a cornerstone of the new space industry. The Applied Research Laboratory is beginning to leverage our extensive capabilities and experience to develop the next generation of spacecraft components and hardware. The Lunar Lion team is already building partnerships with companies to build additive manufactured rocket engines with advanced geometries, and dramatic cost and schedule benefits.”

Devon ponders the global economic impact of the disruptive nature of an emerging manufacturing process, but notes that 3-D printing won’t be able to replace everything.

“Digital fabrication means a cultural revolution that says if you can think of it you can draw it, and if you can draw it you can make it for a very modest investment. You are not limited only to making things in large numbers for a defined market at great manufacturing expense,” he said, because either you must build a large plant or retool one. “There are differences in scale here that translate into differences in imagination. Digital fabrication is a mass market tool that unleashes creativity at the local level.

“This may tip the competitive advantage in radical ways, but go to the dollar store and see what they sell today,” he added. “3-D printing can't compete on price over traditional mass production. It competes on customization, on uniqueness. How big is that market? But it also has big supply chain advantages in time, lower transportation costs and so forth.”  

According to Peter Weijmarshausen, the CEO of Shapeways, which creates 3-D objects for consumers, “We’ve just gotten started, really, and we don’t yet know what we can do. It is like the early Internet years, when we couldn't imagine Web browsing or Facebook or Twitter or Skype. We'll get more exciting materials, we’ll get a mix-up of materials. We can already print semiconductors, and one printer prototype I know can already print batteries — if you have batteries and semiconductors, you have devices.”

Researchers in England are learning how to print aircraft parts in titanium. Instead of wasting 90 percent of a block of the expensive metal as they cut away everything that doesn’t look like a landing strut, for instance, they start with titanium powder and fuse it with lasers or an electron beam and build a landing strut from nothing. Excess powder can be reused, and the finished part only requires about 10 percent as much titanium. Their larger goal is to “print” an entire airplane wing, which will be lighter and stronger than one made the old way, saving enormous amount of fuel. Cutting one kilogram from the weight of an airliner can save as much as $3,000 per year.

“This is a technology which enables and inspires,” Saint John said. “You can achieve much more than you might be capable of otherwise when you have a 3-D printer next to you. In our experience, it helps speed up the development cycle, whether that's the development of a business prototype or the development of the student's capabilities."

The growth of 3-D printing promises to be transformative, which is a nice word to softens a harsh reality that includes both destruction and creation. It won’t happen overnight, whole sections of some industries will go out of business while new ones are born, and a lot of cool-sounding ideas will fail along the way.

“Some results of 3-D printing will be trash and some will have knock-on effects that end up in digital manufacturing with mass markets, but the process is grassroots and will change more things than we can imagine. We are using an open source practice that has accelerated the development and diffusion of the technology immensely. 3-D printing will mature, and will have a huge impact in labs where prototypes both inanimate and animate will be made with truly rapid prototyping in all labs,” Devon said.  

“And time to fabrication and hence social change will become very small. As with social media and journalism, old ways will look like just that as the world of knowledge and design flattens and explodes.”

Peek into the near future if you dare

Pretend it’s a couple of years from now. (Or maybe a little longer.)

You are part of a crew of coal miners working a mile or two below the surface, and a part breaks on the boring machine. Everything stops, since the part has to be replaced for work to continue.

Today, you’d have to make the long trip to the surface, get someone to call the parts supplier and have a replacement part ordered and delivered via an overnight service to the mine. It then would have to make the long descent back down to the coal boring machine. It could take a few days.

But what if the company has equipped each work crew with a portable 3-D parts printer, a computer loaded with CAD digital plans for all the field-replaceable parts on the boring machine and raw materials?

If that were the case, and you were trained to operate the computer and printer, you would log on and print a new part — printing in metals is already being tested — and it would be installed on the spot, rather than in days.

Or imagine a printer that is able to take cells cultured from your body, and a high-resolution CT scan of your aorta. It is theoretically possible in the near future to print an exact replica for a transplant with little risk of rejection, since the cells are your own. With some recalibration, and a different design file stored in the attached computer and using other cells cultured for the purpose, the printer could print human liver tissue to be used by a pharmaceutical company to test a new drug with no risk to a human subject.

Actually, this last example is not futuristic at all.

A San Diego company is developing ways to print living human organs and parts today in the lab. They are making “mini-livers,” just half a millimeter deep and 4 millimeters across that can perform most functions of the real thing. According to an article in New Scientist, “The realistic structure and functioning of the mini-livers make them good predictors of the toxicity of drugs and other substances. They produce albumin, the liver protein that bulks up blood and ferries hormones, salts and drugs throughout the body. They also make cholesterol, which carries fat in the bloodstream, and produce major detoxification enzymes, called cytochrome P450s, that metabolise drugs in the liver.”

What is 3-D printing, really?

For the moment, it is more of a curiosity than a threat to the status quo. It’s relatively more expensive than mass-produced objects and can only compete now on customization, not cost.

Chuck Hull invented and patented stereo lithography in the mid-1980s, when he founded 3-D Systems Inc. Since then, advances in the technology have been — and continue to be — made, including the size of the printers themselves, the materials they can use and more.

Plastic has been the most common raw material so far because of cost and versatility, but objects are increasingly being built from various powdered metals, ceramics and recycled materials. One company is developing a system that, rocketed to the moon, could use moon dust to make habitats for human occupants before they arrive. Another is erecting a building in Amsterdam from printed building materials.

There are various methods of 3-D printing and a handful of materials that can be used. Some items can now be printed in ceramic, glass, stainless steel and precious metals. Researchers are trying to figure out how to print objects from more than one material at a time.

Another key advantage is that objects can be produced with 3-D printing that were simply not possible with older machining and molding and manufacturing techniques. And over time, with experience and new materials and economies of scale, the costs will come down.

Designers are beginning to realize that intricate shapes can be produced that a traditional lathe or stamping machine could not attempt. It’s also theoretically possible to mix different raw materials and print fully assembled complex items with all components already in place.

Imagine a cell phone that can be “printed” from a mix of materials, including plastic and metal and ceramics, complete and functional in three dimensions, with all circuit boards and even batteries included. Or consider car dashboards with all internal components such as wiring harnesses, dials and knobs, coming out of the printer ready to install in your new car.

Or, imagine going to a furniture store and buying what they say is a chair — made with a specialized printer out of special materials but rolled up in a tube. When exposed to water, the material begins to shape itself into a chair. The possibilities exist to make things that assemble themselves, smart things — programmable matter that can think in primitive ways and respond to stimuli.

These might not be profitable yet, because mass production techniques and economies of scale are much cheaper today. But it is conceivable that subcomponents could be printed as a whole in the near future, eliminating some manual assembly labor costs.

For the time being, ordering “Tea. Earl Grey. Hot” and an organic blueberry muffin from your home replicator is probably a decade or two in the future. But one can order custom-printed objects both artistic and practical over the internet now.

The possibility of things even more fantastic, and a technological revolution on a par with the printing press or the Internet, is being built here in labs and classrooms — and around the world.