3D Printing Increases Watch Assembly Quality
While studying for a master’s degree in architecture at Delft University of Technology, Michiel Holthinrichs began to collect and repair vintage watches. He turned his passion into a business, founding Holthinrichs Watches in 2013.
Holthinrichs produced his first design iterations traditionally, developing them into hand-drawn technical drawings and taking into consideration that the parts would be produced using CNC machinery or on a manual lathe. However, he did not have the machinery or skills to produce them himself, so he needed to find a manufacturing partner. Additionally, the Netherlands does not have an established watchmaking industry.
After researching the trend of 3D printing for manufacturing, Holthinrichs discovered Renishaw plc, a manufacturer of metal additive manufacturing systems. He contacted Philippe Reinders-Folmer, the general manager of Renishaw Benelux, who suggested a reputable 3D printing bureau in Belgium that had recently installed a Renishaw AM250 system. Holthinrichs worked with the bureau to print prototypes, including the first Ornament 1 watch.
The case, crown and buckle of the Ornament 1 were printed in stainless steel 316L. The watch case has a diameter of 38 millimeters and is only 10 millimeters thick. It features a raised inscription of the Holthinrichs brand on its edge with the words “stainless steel,” “3D printed case” and “Swiss movement” in capitals on its reverse. These intricate details were only possible with additive manufacturing.
The batch of watches took approximately 30 hours to print on the Renishaw AM250 system. Following post-processing, the watches were returned to Holthinrichs, who finished them with hand filing and polishing. The post-processing, assembly and adjustment by hand took an additional 30 hours per watch.
Once Holthinrichs was able to produce Ornament 1, he wanted to investigate how reproducible it was and to streamline the labor-intensive finishing process. In addition, his manufacturing costs were relatively high because the metal 3D printing, machining and other automated post-processing all had to be outsourced. After an evaluation by Renishaw, it was concluded that a Renishaw Additive Manufacturing Solutions Center (AMSC) would take Holthinrichs forward on his journey in metal
Renishaw Additive Manufacturing Solutions Centers allow customers to rent time with Renishaw additive manufacturing technology with the support of Renishaw engineers. Services at an AMSC can cover the full production process from design for additive manufacturing through to finishing and inspection. Customers have access to complementary technologies, such as machining and metrology.
Based on the success of the Ornament 1, Holthinrichs wished to offer the watch in an alternative material. Renishaw recommended titanium because of the high-polished finish and that it’s suitable for investigating chemical post processing, which could reduce finishing time. Also, titanium is lighter than stainless steel, providing an additional difference in the design range. Through training at an AMSC, Holthinrichs was able to draw his design with 3D computer aided design software.
“If Michiel wants to tweak a design or change an engraving or a signature he can do that on his computer and there’s no knock-on effects further down the process line,” explains Charlie Birkett, a Renishaw additive manufacturing applications engineer who supports customers in the UK AMSC.
Renishaw exported Holthinrichs’ new design into its QuantAM build preparation software. Once the build was prepared in QuantAM, the file was sent to a Renishaw AM400 metal additive manufacturing system. The AM400 was chosen for its flexibility in terms of material changeover and ability to reproduce sharp corners and the fine detail in the design.
Renishaw and Michiel will now investigate several manufacturing and post-processing solutions to improve his production time, ensuring all the while that the parts are of the highest quality. “We are just at the beginning,” states Holthinrichs, “so I am very curious as to where it goes.”
For more information on additive manufacturing, call 847-286-9953 or visit www.renishaw.com.