7 Questions with 3D Printing Icon Charles Hull


Charles Hull. Image: 3D Systems

“I kind of look at them as all my children and it’s hard to pick a favorite,” says Charles “Chuck” Hull, the co-founder and CTO of 3D Systems, about existing applications of 3D printing. When you have invented a technology and seen it grow from birth to adulthood over 30 years, it’s natural to feel that way.

An active private pilot and an avid photographer, 76-year old “father of 3D printing” Hull holds numerous patents worldwide and has received several prestigious awards, including being inducted into the National Inventors Hall of Fame, for his invention and commercialization of stereolithography – the first commercial 3D printing technology. His invention, the SLA-1 3D printer, is being recognized as a Landmark by ASME this year. 

After receiving a B.S. in engineering physics from the University of Colorado, Hull moved to California to pursue his engineering career, first as a senior engineer at Bell & Howell and then as an engineering manager at Du Pont. He developed and patented the stereolithography process at UVP, Inc., where he served six years as vice president of engineering. With the founding of 3D Systems in 1986 he initiated the 3D printing industry – a juggernaut that’s reinventing manufacturing in America today.

During his early career, Hull got involved in design projects for plastic components. “The time between when you had the design finished and you saw your first finished part was typically six weeks and then if you found problems with it you had to recycle,” he says.

He recalls working on several applications in ultraviolet radiation at UVP and one of those being UV curable polymers, which were thin sheets of plastic. “When I saw these UV curable coatings,” says Hull, “I thought was there any way I could do some kind of imaging and manipulation to make prototypes of plastic parts? That’s how I got the idea of stereolithography in the first place.”

In ASME.org’s recent podcast, Hull spoke about the early days of 3D printing and how it continues to change the face of manufacturing. Here are a few snippets of the conversation.

Q1. After you invented stereolithography and created the first 3D printed part, what changed?

Hull: I 3D printed the first part in 1983. I spent time after that trying to further perfect the technology and get the first patent application in place. Once that happened it was a question of commercialization. After I presented the business plan to the company I was with, we decided to spin off another company and licensed the technology I had developed into this new company. What changed then was the formation of the first company – 3D Systems – that was really the beginning of the additive manufacturing industry. 

Charles Hull’s self-portrait bust and his SLA-1 3D printer at The National Inventors Hall of Fame. Image: National Inventors Hall of Fame / 3D Systems

Q2. When did you first envision 3D printing being used in manufacturing?

Hull: We started the company in 1986 as a development company. We had our first product then to sell first as a beta system at the end of 1987 and then commercially in 1988. That was the first 3D printer, the SLA-1. We envisioned it for prototyping applications but right away our customers started mentioning the potential for manufacturing applications. One of the first manufacturing applications we pursued was casting patterns. We then started to see a vision of how it could be used in manufacturing. Of course this was all very short-run manufacturing at that time.

Q3. What pushed the technology into full commercial use?

Hull: The first major users of the technology were engineers in the automotive industry. The problem back in that era was that the US and to some extent the EU automotive industry were falling behind Asian manufacturers, in terms of how quickly they could produce new cars. They were looking for ideas and technology to help speed up the design process. 3D printing became a big part of that along with 3D CAD, which was just emerging at that time. These companies along with aerospace companies helped push it forward to commercial use.

Q4. Currently there are several new technologies and 3D printers promising speeds of printing unheard of before. What’s your opinion on that?

Hull: I am a big promoter of that. We recently demonstrated a high-speed system which is a cell of three 3D printers, with robotic arms to pull out the parts and place on finishing stations, and present them at the end for the next step in an industrial production line. Our idea is that we will produce these small high-speed 3D printers and help companies integrate those into the production lines. This kind of technology is going to be very important in taking additive manufacturing to production.

3D Systems at the Grand Opening of the state-of-the-art Healthcare Technology Center. Image: 3D Systems

Q5. The last five years have witnessed a 3D printing boom but will it continue in the next decade?

Hull: Absolutely, and there are a few ways to look at this boom. There was certainly a kind of hype element to it where people were expecting 3D printing to instantly do everything and that hype I think has kind of subsided. The good thing is that it’s created a general awareness in not just industrial people but the population as a whole understands what 3D printing is. Thousands of companies around the world are implementing the technology. It is definitely on a growth curve and in that sense it has spread to all the corners of the world. That will continue to the next decade and beyond.

Q6. As an engineer, what has been your biggest learning from the day you invented 3D printing until now?

Hull: Not a day goes by when you don’t learn something. Probably the biggest for me is that I had been an engineer and as I was developing this technology, I was also studying and learning entrepreneurship, so basically learning how to grow a startup business. I had to learn more about the business side in order to make 3D printing happen.

Q7. What’s your advice to young engineers who hope to invent a disruptive technology?

Hull: It’s very exciting to see lots of young entrepreneurs nowadays. There are really two keys – one is being the very best engineer that you can be. For example, if you are a mechanical engineer or whatever your engineering field is, understand that discipline in great depth and be an expert. The other is to do a lot of interfacing with other engineering technologies and with other professions because it’s the intersection of the knowledge you have with the issues and problems that you encounter in the broader society is where disruptive inventions happen. You need both the elements to be a good engineer.

Listen to the Podcast: How Charles Hull Conceived 3D Printing

Learn more about the latest technologies in 3D printing at ASME’s AM3D Conference & Expo.

The intersection of the knowledge you have with the issues and problems that you encounter in the broader society is where disruptive inventions happen.

Charles Hull,
co-founder and CTO, 3D Systems


May 2016

by Chitra Sethi, Managing Editor, ASME.org