How Brose Leverages SLA and SLS Technology to Bolster Automotive Production

One in every three new vehicles coming off the assembly line today has at least one component manufactured by Brose — one of the five largest family-owned automotive suppliers in the world. Started over 100 years ago in Berlin by Max Brose, the company has grown from an automobile accessories trading business into a market leader in mechatronic systems. Their products — mostly seat, liftgate, and door assemblies — are designed and produced for the biggest names in the car world: BMW, Volvo, Ford, Mercedes, Jeep, and more.

Brose’s steady growth and their long-term successful partnerships with these OEMs are due in part to the company’s commitment to continuous innovation and improvement. 3D printing is at the core of multiple initiatives in Brose’s design and end-use manufacturing processes and has helped Brose adapt and respond to all the changes in the fast-paced automotive industry.

We visited Brose North America, their headquarters in Auburn Hills, Michigan, as well as Brose New Boston in New Boston, Michigan, one of their largest end-use manufacturing facilities, to see how they’ve put powerful stereolithography (SLA) and selective laser sintering (SLS) 3D printers into action. Seat Division Prototyping Manager Matthias Schulz who is leading Additive Technology as well in the region, spoke to us about how Brose uses 3D printing throughout their entire process, from design to manufacturing to end-use parts on tight timelines for OEMs.

Prototyping as an application is a perfect — and familiar — fit for 3D printing. While Brose does employ a range of fused deposition modeling (FDM), SLA, and SLS 3D printers for prototypes, their volumes aren’t necessarily what one might expect for proof of concept parts. For Brose, a typical volume for prototypes is closer to 500 or 1000. 

“We use 3D printing on a larger scale. ‘Prototyping’ means we have to print several hundred parts, mostly related to the number of tests that we have to do. Not only do we fulfill internal and external standards, but also federal requirements. Those, of course, require us to do a certain amount of parts, and that usually leads to seven to eight hundred parts that we have to print for a prototype,” says Schulz. 

For one project, the prototype team needed to use a soft silicone dampener which is installed in the seat assembly. As the seat moves forward on its frame, the part dampens the sound and improves the haptic and acoustic feedback of the seat assembly movement. To order these parts from a Brose serial supplier overseas, the minimum order quantity was in the millions — and Brose only needed a few hundred for use in a preliminary design test.

Besides the high cost of ordering several million parts and shipping them overseas, the lead time was several weeks, and the millions of parts that weren’t needed would require storage before ultimately creating waste. Instead of ordering the part, the existing CAD was used to quickly 3D print several hundred of them on Form 4. They were ready in a week, and the solution reduced the overall costs and lead times of the entire project.

When components increase in complexity, size, and required volume, Brose turns to his fleet of three Fuse Series SLS 3D printers for prototypes and production. SLS 3D printing with its self-supporting print bed enables fully packed production volume builds, and the strength and mechanical properties of sintered nylon make the technology ideal for end-use components. For a recent project, Brose’s Additive Technology team used both SLA and SLS technology to prototype a seat suspension mat.

They printed the translucent, flexible parts in Durable Resin on their Form Series SLA 3D printers, and the mat’s connection tubing in Nylon 12 GF Powder on their Fuse Series printers. For each mat prototype, there were six SLS parts and three SLA parts, but in total, the team assembled 150 of these full mats to be tested as part of complete seat assemblies.

With rapid prototyping tools in-house, Brose was able to design, test, and iterate a vital component of their seat assembly product without tooling or outsourcing. “Sometimes the combination of both SLA and SLS is the answer, like on this seat suspension mat. An overmold tool is very complex and expensive, so we designed the parts to snap over the wire for the SLS and installed the SLA parts in a “green state” on the wire and cured it that way,” says Schulz.

Additive manufacturing isn’t only being used as a prototyping tool at Brose — they’re integrating the technology across all departments as part of their Plant Goes Additive initiative, which launched in 2022. Automotive manufacturing is non-stop and highly controlled — every part of the process has been lean and optimized for efficiency as well as safety and product excellence.

As Schulz says, the automotive industry has been changing fast, especially in the last five years. The rise of EVs, the growing demand for customized features, and supply chain concerns have prompted OEMs to invest more heavily in additive manufacturing as a reliable alternative for production.

“We do have more and more customers requesting additive technology. It also plays a role with the customer interface for the end-use customer, because they would like to have more personalization in their vehicles, and therefore, additive technology is being asked for more and more by the OEMs,” says Schulz.

3D printing for end-use parts, especially in the highly regulated automotive industry, hasn’t always been possible. Brose’s additive manufacturing team has made sure they moved to end-use production only when the quality of the hardware and materials could deliver high-performance parts reliably.

Brose uses 3D printing for end-use production as an affordable, fast alternative to traditional manufacturing. When an OEM requests a part, or a change to an existing part, that cannot be tooled and mass-produced fast enough, the additive division at Brose evaluates if 3D printing is suitable. A big part of that is reverse engineering and scanning existing components.

This component is a Bowden release — 20,000 of these parts will be printed on Brose’s fleet of Fuse Series SLS 3D printers and included in the final seat assembly for a large, well-known OEM.

“Brose decided to bring SLS with Formlabs in-house because the SLS technology allows us fast and rapid 3D printing that has less post-processing requirements than we see on SLA. We can print high volume quantities, which is necessary for us to support gap printing or other OEM-related end-use customer parts,” says Schulz.

With three Fuse Series SLS 3D printers working nonstop to produce prototypes, manufacturing aids, and hundreds of thousands of end-use components, reliability and consistency are key. The team uses Nylon 12 GF Powder for its dimensional accuracy and close resemblance to injection molded nylon, even at production volumes. After each full build, a quick maintenance check on the Fuse 1 or Fuse 1+ 30W takes just about fifteen minutes, ensuring continuous, efficient production.

“Formlabs understands how to build a printer that is easy to maintain. The equipment is very reliable and we hardly see any failed prints, so we can commit to printing higher volume parts and have the confidence to go to production,” says Schulz.

Brose’s commitment to continuous improvement has led them to invest in new technologies like additive manufacturing and automation to streamline their processes and deliver innovative solutions for each of their customers. As 3D printing begins to take a bigger and bigger role at the company, champions like Schulz are committed to finding new ways to leverage its quick turnaround times and (frequently) lower costs. 

With fast, powerful tools like Form 4, Form 4L, and the Fuse Series, prototyping, manufacturing aids, and end-use components can be turned around in hours or days, rather than weeks or months. “Formlabs is the right partner to work with. We needed a turnkey solution that could produce parts in higher volumes and with less engineering support. The software, support, and printers from Formlabs are the right fit.”

To learn more about 3D printing in the automotive industry, visit our website. To see the quality of SLA or SLS 3D printing for yourself, request a sample.