There are a lot of secrets in the world of design – materials, processes, handshakes and very few know how many raccoons it takes to gnaw a smooth continuous surface out of a chunk of clay. Perhaps that’s changing and perhaps it’s beginning with knowing a little more about the secret process behind modern concept car design.

As a matter of fact, you may slap the stingy portion of your friends back to find out our 3D printing pals over at i.materialise have been behind one of the secrets this whole time… they don’t mind it either. Following up with them on an Autotopia article about 3D Printing, we asked Joris Peels of i.materialise about the process of going from concept model to 3D print to make these concepts come to life.

What does Materialise do to go from customer concept, their model, to 3D print?

“This depends on a lot of factors. But typically a design will come in either uploaded to us or sent to an engineer at Materialise if it’s a business customer. Typically the i.materialise customer designs are relatively easy to print and most of the process is automated. But, even then we have a person evaluate a file just to be sure. The file is checked and repaired if need be. We have a department that does this. We also have a CAD department that looks at the challenging parts and projects to determine if they are buildable and how it would be done.

With the technical and complex projects we often need to work with the customer to get it just right and to make sure we understand what they want. Because we have to get it as perfect as we can in the system so everyone can check and immediately see what idea we have to make. We’re a factory for people’s ideas. In order to make sure that we 3D print the right idea, we have to understand the customer and their part. We also need to know what kind of finish they want and what the part has to do. Does it need to conduct electricity? Do they want to paint it? Shall we? How accurate does it need to be? What is it going to be used for? Is it a buoy someone wants to toss into the ocean, a bobsleigh, a prototype for a consumer electronics device that has to look perfect for the CEO? This kind of understanding is crucial to advise them on what we can do for them and which 3D printing process and finish is appropriate.

Once we’ve determined the level of finish and technical requirements this is stored in the system. The part is sent to a person who determines which orientation the part should have in the 3D printer in order to get the best result. Then support structures are generated for the part. The part is nested in a virtual 3D printer build volume and sent to the machine. The machine then 3D prints the part, this might take only a few hours but for the largest parts it takes days. Then the part is removed from the 3D printer, the support structures are removed and the part is washed and UV cured. Then the part is taken to the finishing department.

Sometimes customers don’t need a high level of finish and this is then easy to do. But, in the case of a concept car, a master for a mold or something that requires a very high level of finish there is a considerable level of work to be done. A person in the finishing department gets the 3D printed part and reads up on it to understand it. They will first remove all traces of the support structures by sanding by hand. Then they will sand the entire part by hand with three levels of sanding. The person has to keep checking to make sure the part is completely smooth.

At the same time they have to understand the designer’s intent in order to continually weigh the options. How important dimensional accuracy is versus a smooth part for example. They have to make those decisions themselves and be part engineer, part designer and all artisan while they carefully sand for hours to get the perfect result. Then the part is painted, we can do any color and many different finishes. For some customers we also do assembly. Then it is sent to the shipping department and they concoct a container to ship it with. Again with small parts this is easy with larger ones we have to build them by hand.

Now that, is exactly what you don’t hear about. Thanks Joris. Wondering what the culmination of all that work is? Well, here is what you’ll see at the car shows, on the auto blogs and the concept car calenders. This is the Citroën GT, a car that was birthed on the Playstation game Gran Turismo 5 and then re-birthed through the process of 3D printing. Six of the cars are being built for a price of $2 million each (source). If you’re wealthy enough to have purchased one, you can thank 3D printing and i.materialise for making it happen.

Big hat tip to Butch Lively of TDA for sending in the article on 3D Printing Concept Cars!


Josh is co-founder of EvD Media. He engineers and designs, is the Director of Marketing for Luxion, is CSWP certified for SolidWorks training and support and excels at falling awkwardly. He is editor of and co-host of, a weekly podcast about design, engineering and what makes it all happen.