The History and Future of 3D Printing - What Is 3D Printing? - Idiot's Guides: 3D Printing (2015)

Idiot's Guides: 3D Printing (2015)


What Is 3D Printing?


The History and Future of 3D Printing

In This Chapter

· The development and history of 3D printing

· How the RepRap project accelerated development

· Predicting the near future of consumer 3D printers

If you want to understand something, it’s always a good idea to begin by looking at the history. It’d be difficult to truly understand how a car works, for example, if you didn’t know how the internal combustion engine was developed. 3D printers are no exception to the rule, and for such a new product they have quite a rich history.

In this chapter, I take you through the history of 3D printing and the effects of its evolution on you now and in the future.

3D Printing Is Born

3D printing has just entered the public consciousness in the past few years as consumer 3D printers have become available. But 3D printing has actually been around for decades in the industrial world. 3D printing revolutionized the way companies produce prototypes, and that provided the basis for consumer 3D printing.

So how was 3D printing actually developed? Who invented it and why?

Hull’s and 3D Systems’ Contributions

The first patent for a 3D printer was filed in 1984 by Charles W. Hull. His patent was for a 3D printing process called stereolithography (SLA), which used UV light to cure photopolymer resin in a vat to form parts. Hull, an engineer specializing in materials science at the time, came up with the idea for SLA while working on resin coatings for tabletops.


Photopolymer resin is a type of liquid resin that solidifies into plastic when exposed to light (usually in the ultraviolet spectrum). Manufacturers can produce the resin in many varieties, with different mechanical and chemical properties.

The company Hull was working for at the time, Ultra-Violet Products (UVP), employed him to develop UV-curable coatings to improve the durability of tabletops. These coatings were a liquid resin that reacted with UV light to become solid plastic. While working with this resin, Hull started imagining a device which could cure this resin in successive layers to form a three-dimensional object.

Hull took his idea to UVP and was granted permission to work on a prototype device on nights and weekends, while continuing his normal duties during the day. The development process was not without its hurdles, one of the biggest being how to translate a 3D computer model into printing instructions for his SLA printer.

At the time, in the early ’80s, computer-aided design (CAD) was still in its infancy. 3D modeling was a difficult process, and not a whole lot could be done with the resulting models. Hull knew he needed 3D models in a file format that could be used to create instructions for his printer, but no suitable file format existed. So Hull created his own: the SLA file format, abbreviated as STL, which is still the standard today. (These days, because the STL file format is used in a wide range of manufacturing processes, STL is often considered an abbreviation for standard tessellation language.)

The STL file is created by taking a 3D model from CAD software and converting it into a surface mesh consisting of many triangles. The beauty of the STL format is that the number of triangles determines the detail of the resulting surface mesh, making it scalable. With this file format in hand, Hull was able to create software to translate the 3D model into a series of instructions for his printer to follow.

In 1983, Hull successfully printed his first 3D model: a basic cup. Knowing he had a viable and useful new method of rapidly creating prototypes, he filed his patent for SLA in 1984. In 1986, his patent was granted, and in the same year he created his company 3D Systems to develop and sell SLA printers.


While Charles W. Hull did patent his SLA process, he didn’t patent the STL file format that he developed. This has allowed STL files to be used by other 3D printer manufacturers and even in other types of machines, like computer numerical control (CNC) mills. For this reason, the STL file format has become the standard for 3D printing and CNC milling.

The Invention of FDM Printing

The fused deposition modeling (FDM) printing process—a technology used by the vast majority of consumer printers today—was originally developed by Scott Crump in 1989, in order to ease the process of prototyping at IDEA, Inc., a company he cofounded in 1982. Crump, along with FDM printing itself, also developed some of the necessary associated technologies (such as ABS filament, which I’ll discuss more in Chapter 4).

After inventing the FDM 3D printing process in 1989, Crump founded Stratasys—currently the largest 3D printer manufacturer—with his wife Lisa. In 2009, Stratasys’s FDM printing patent expired, opening up the market for consumer FDM 3D printers, usually referred to as fused filament fabrication (FFF) for non-Stratasys 3D printers.

The Development of Other 3D Printing Processes

During the same time frame that Stratasys and 3D Systems were developing SLA and FDM 3D printing, other 3D printing processes were being developed independently. At the University of Austin in the mid-1980s, selective laser sintering (SLS) was developed by Dr. Carl Deckard and Dr. Joe Beaman with sponsorship from Defense Advanced Research Projects Agency (DARPA). This technology was originally sold by DTM Corporation, which was then purchased by 3D Systems in 2001.

Meanwhile, in the early ’90s at the Massachusetts Institute of Technology (MIT), inkjet 3D printing was invented. Z Corp. gained the license for this technology and produced inkjet 3D printers until 2012. On January 3, 2012, Z Corp. was purchased by 3D Systems in order to acquire the associated inkjet printing patents and licenses.

Due to the expiration of key patents, many of these technologies are starting to enter the consumer market (or will be soon). But it was FDM printing that jump-started consumer 3D printing. This was mostly thanks to the RepRap project.

The RepRap Project

3D Systems, Stratasys, and others revolutionized research and development with 3D printing. But for many years, 3D printers remained expensive and complex tools. The high learning curve to use them meant that most users needed special training, and their high cost meant they were out of reach for an individual person. That remained true until the RepRap project was launched in 2005 by Dr. Adrian Bowyer, an engineering lecturer at a university in the United Kingdom.

Initial Intentions

When Dr. Bowyer first founded the RepRap project, his intentions were simple: to develop an inexpensive open-source 3D printer, with a long-term goal of self-replication. The name “RepRap” is a contraction of “replicating rapid prototyper.” The idea is that the best way to get a 3D printer into as many hands as possible is to design a 3D printer that can 3D print a copy of itself. If each person prints two new printers for friends, the spread would be exponential, and before long, everyone would have small-scale manufacturing at their fingertips.

The goal of self-replication is a long way off from fruition; it is a lofty goal, after all. Such a design would have to be capable of not only printing the plastic frame pieces, but also motors, electronics, and other complex nonplastic parts. But that optimistic long-term goal has yielded bountiful developments for consumer 3D printers.

The Importance of Open Source

One of the core tenants of the RepRap project, possibly the most important of them, is that it is completely open source. Every design and development is completely public, allowing anyone to use the designs and contribute to the project.

Anytime a new breakthrough is made, it can be immediately released and integrated into the design of new printers. A good example of this is the RepRap Arduino Mega Pololu Shield (RAMPS) control board, which is essentially the brain of the 3D printer. The RAMPS board connects to an Arduino (another open-source project) to provide computer control of the 3D printer’s motors and extruder. The development of RAMPS allowed people to quickly, cheaply, and easily control their 3D printers, so it was quickly integrated into the design of subsequent RepRap printers.


Arduino is an open-source platform for developing and prototyping electronics. Arduino models are generally small circuit boards without inputs and outputs for controlling various electronics. The Arduino Mega is used by the RAMPS control board for 3D printing.

The same is true of any other new RepRap development. Because it’s open source, there are no patents to deal with, and the new development can be freely used and improved. This concept has been essential to the success and rapid evolution of RepRap 3D printers, and consumer printers in general.

Rapid Development

Due to their open-source nature, RepRap printers have evolved extremely quickly. The first complete design, the Darwin 3D printer, was released in 2007. Darwin was a very basic design, wrought with limitations and capable of only mediocre-quality printing, but it proved that 3D printers could be inexpensive and built at home by hobbyists. Like most subsequent RepRap printers, and consumer printers in general, Darwin utilized the fused filament fabrication (FFF) 3D printing process. FFF is exactly the same as FDM in practice (filament is melted and squeezed out of a nozzle in lines, forming layers) and was only named differently to avoid legal problems with Stratasys, who patented the FDM process.

The RepRap Darwin, which was the first design released by the RepRap project.

In 2009, a new RepRap design called Mendel was released. It made a number of improvements to the Darwin design, which increased reliability and print quality and decreased the difficulty of building the printer. Mendel integrated many developments that had been made between 2007 and 2009 into a complete package, which would be a continuing trend with new designs that followed.

By the time the Prusa Mendel and Huxley RepRap designs were released in 2010, the community had already grown tremendously. Many offshoots and derivatives of the standard models already existed, making improvements and customizations to suit individual tastes. Today, there are at least 30 official RepRap designs, with derivatives numbering in the hundreds. Current designs rival the consumer printers being released by companies like 3D Systems and Stratasys, who independently developed their own (closed-source) designs. RepRap printers have achieved quality and reliability so high that they’re even being used in professional prototyping settings.


RepRap models, following the convention set by the original Darwin, are named after notable evolutionary biologists. However, some derivatives, such as the Prusa Mendel, are named after their designers or names they chose.

Refinement, Availability, and Your Wallet

The jump from expensive professional 3D printers to consumer 3D printers happened astonishingly quickly. In just a few years, consumer 3D printing went from being experimental, unreliable, and difficult to something that could feasibly be taken advantage of by the average hobbyist. So how did that rapid evolution happen, and what drove it? That was largely due to the development pioneered by the RepRap project.

Until the RepRap Darwin proved that consumer 3D printers were feasible, virtually all 3D printers were expensive professional machines meant for corporate buyers. But with the success of the RepRap project, consumer 3D printing was suddenly on everyone’s mind.

3D printer manufacturers specializing in inexpensive models intended for home use began popping up rapidly. Some of these manufacturers sold printers based on RepRap designs, while others developed their own. However, even those that developed their own did so with knowledge and information that often originated with the RepRap project.

In the short time since Darwin was released in 2007, the consumer 3D printer market has grown exponentially. Prices have dropped from the tens of thousands of dollars to just a few hundred dollars for the least expensive printers. But it’s not just the price that has changed. The quality of available 3D printers has evolved by leaps and bounds as well. Just like with the Cambrian Explosion, the market has gone from being essentially nonexistent to being a huge and diverse ecosystem full of evolved and refined 3D printers.

What does that explosion of 3D printer evolution in recent years mean for the current market? With such a short history, you might expect that 3D printers aren’t quite ready for mainstream use, and to an extent you’re right. 3D printing in the home is still pretty experimental, and it’s not as simple as printing on a sheet of paper with an inkjet printer. But 3D printing is a revolutionary and exciting technology, and the pace at which it’s improving is astounding.

Maturation of Technology

No matter what the particular product is, you can bet that it will improve as the associated technology matures. This has been especially evident since the advent of personal computing. The first personal computers were big, expensive, slow, and weren’t particularly useful. But the technology improved so quickly that within a few years, prices had dropped dramatically and usefulness had improved exponentially. Of course, now the technology is so good that computers are ubiquitous.

A similar metamorphosis is happening with 3D printers right now. We’re already past the “expensive and useless” stage now, and we’re well into 3D printing entering mainstream use. As the technology has matured, proven formulas and design principles have started to emerge.

In the early days of consumer 3D printing, everything was still highly experimental. Engineers were still trying to figure out the best way to design printers, individual parts were still being cobbled together from whatever was available on the market, and printing methods and practices were still being developed. Now we’ve entered a stage of refinement. We’ve got the basics down, there is a solid knowledge base with which to work from, and industry standards have started to form.

At this point, printer manufacturers are no longer trying to simply invent a practical 3D printer; instead, they’re improving the functionality of proven designs. In the same way that auto manufacturers refine existing engine designs rather than inventing new engines, 3D printer manufacturers are now working on refining their printers to make them better and more useful.

Availability of Parts

As a technology matures, there is also a significant increase in the availability of parts specific to that industry. When a company like Dell decides to build a new laptop, they don’t manufacture all of the individual parts from scratch. Instead, they purchase processors from Intel, memory from Corsair, hard drives from Seagate, and so on. These parts are all standardized, and Dell can purchase them knowing they’ll work together. They can then assemble the parts into a working computer of their design.


Just 10 years ago, in 2004, the most inexpensive 3D printers available still cost about $25,000. Now, in 2014, functional 3D printers can be purchased for as little as $200. This perfectly illustrates the effect that development and parts availability has had on 3D printer prices.

The same process is true in most industries. But until recently, 3D printing was so new that individual parts simply weren’t available to printer manufacturers. Manufacturers were forced to either repurpose parts used in other industries (which may not be well suited to 3D printing) or make them themselves (in which case, quality and cost became a problem). The lack of parts available in the 3D printing industry was a huge factor in the high costs of early consumer printers.

But that has started to change. Many parts are starting to become available to printer manufacturers. Just like Dell can order a processor from Intel, a 3D printer manufacturer can now order a hot end, control board, or heated bed for use in their printers. This has greatly reduced the costs involved in designing and manufacturing 3D printers and has also improved quality.

Instead of the printer manufacturer having to try and design each and every individual part with marginal results, they can now order them from a company which specializes in that individual part. E3D, for example, is a company that makes hot ends for 3D printers, and that’s all they do. Because it’s their sole focus, E3D can concentrate on just trying to make the best hot ends on the market. Printer manufacturers can then purchase those hot ends for theirprinters and have a high-quality part without a massive design and manufacturing investment.

A hot end manufactured by E3D that’s intended for use on a variety of printers.

With companies like E3D producing parts specifically for the 3D printing industry, the quality of consumer 3D printers has increased very noticeably. And that will only get better as new manufacturers of parts enter the market and competition increases.

The Race to the Lowest Price

That competition between part manufacturers, and the competition between 3D printer manufacturers, has done wonders for the consumer market. Competition in the marketplace always fuels progress and innovation, and that has been particularly evident with 3D printers because it’s happened so fast. In the short time since the RepRap project was started, a large number of 3D printer manufacturers have sprung up. Virtually all of them have the same goal: to provide a high-quality and easy-to-use printer to consumers at the lowest price possible.

Originally, that lowest price was still pretty high. But as parts availability has increased and designs have matured, those prices have been falling like a rock. 3D printers are now under $350, when originally the cheapest consumer printers were still thousands of dollars.


While prices are certainly going to keep going down, they’re already starting to level out. So if you’ve been waiting to purchase a 3D printer until prices drop, don’t expect them to get dramatically lower (at least not for a worthwhile model).

However, the race to have the lowest prices can only go so far before it levels out. Materials and manufacturing are always going to be an unavoidable expense for 3D printer manufacturers, and there will be a point when it’s just not possible to sell printers any cheaper. We may not even be that far from that point today.

The good news is that just because prices can’t drop anymore, that doesn’t mean progress can’t still be made. Once prices level out, the new race will be toward making the best printer at that price. A $500 computer that you buy today will vastly outperform a $500 computer from 10 years ago. And something similar is likely to happen with 3D printers in the future. Prices might level out at around a couple hundred dollars, but what you get for that money will continue to get better and better as time passes.

The Least You Need to Know

· 3D printing was originally invented by Charles W. Hull. He also started 3D Systems, which remains one of the largest 3D printer manufacturers. FDM 3D printing—the technology used on most consumer 3D printers—was invented by Scott Crump, who went on to found Stratasys with his wife Lisa.

· The consumer 3D printer market was largely nonexistent until the RepRap project fueled open-source development.

· 3D printer prices have decreased dramatically as the technology has matured and parts have become available. Quality, reliability, and ease of use have simultaneously improved as a result.

· While the cost of 3D printers is sure to lower a little bit more, prices are starting to level out. However, the printers themselves will almost definitely improve a great deal in coming years.