Arc Bicycle: The world’s first 3D printed steel bicycle frame

When it comes to 3D printing, the choice of materials with which to bring your creation to life is almost limitless compared to the early days of the 1980s. The process of 3D printing, or additive manufacturing, can now render a scale model or even fully functioning end product using anything from plastics and nylon through to silver and gold; even wood has been successfully 3D printed at a commercial scale. In a world-first however, a team of five students from TU Delft in the Netherlands have pushed the boundaries of 3D printing, creating a full-sized, fully functioning 3D printed bicycle from stainless steel.

Designed and developed as part of a research project into the viability of 3D printing using a welding machine, the team made their bike frame a reality with the help of robotic 3D printing pioneers MX3D. The open mesh frame was printed using a mechanical ‘slave’, or robotic arm, that welded on tiny beads of molten steel in a process known as wire and arc additive manufacturing (WAAM). By using these robotic arms, metals and even resins may be 3D printed in mid-air in any direction, without the need for external supports.

Harry Anderson of the ARC Bicycle Team said, “3D printing has exploded in popularity in the last decade, but for those wanting to print medium to large scale objects, there are still significant limitations in the technology. This method of 3D printing makes it possible to produce medium to large scale metal objects with almost total form freedom.”In the search for a real, functional object with which to put the printing method to the test, the students say a bicycle frame, given the complex forces exerted on it when used, makes for the perfect guinea pig. Weighing in at just under 20kg, the bicycle may be a little on the heavy side, but it proved as strong as any other when the students took it for a spin around the cobbled streets of Delft.“Our main concern when designing the frame was the strength. We didn’t know how the material would behave, so we chose to make it extra strong and sacrifice a bit of weight. Our frame proves it’s possible to produce a bicycle frame in this way, and that was our goal,” said the team.

Building the bicycle up steel bead by steel bead was no quick process, taking the mechanical arm around 100 hours to complete the project. The final pieces were then welded together by hand, before students added the finishing touches and took it for a ride.

The first of its kind ever produced, the team hope others will build on their research in designing the bicycles of the future. As for the 3D printing method, the frame is a functioning proof of the concept developed by MX3D. So sure is the research and design company of their groundbreaking technology, MX3D have released plans to use their multi-axis robotic arms to 3D print a bridge across water in the centre of Amsterdam.