1. Recreating legends
2. What is metal additive manufacturing?
3. The Mercedes-Benz R107 rosette dilemma
4. Reverse engineering and the industrial 3D printing process
5. Why we chose 316L stainless steel
6. Achieving the perfect mirror-finish
7. The future of automotive heritage restoration
Recreating legends
Traditional automotive manufacturing relies on subtractive methods like CNC milling, which cuts material away, or casting, which requires expensive molds. Metal Additive Manufacturing builds components layer-by-layer directly from a digital file.
For this project, we deployed Laser Powder Bed Fusion (LPBF) technology using the advanced MetalFAB system. In this process, a high-precision fiber laser melts micro-fine layers of metal powder, fusing them into dense, solid structures. This approach ensures zero material waste and unlocks unparalleled geometric freedom, allowing us to replicate internal channels and complex OEM contours with total accuracy.
The Mercedes-Benz R107 rosette dilemma
The Mercedes-Benz R107 (produced from 1971 to 1989) is celebrated for its interchangeable hardtop and softtop systems. To secure and beautify the roof mounting points, Mercedes designed specialized chrome rosettes.
Unfortunately, the original components were manufactured from soft alloys. Decades of mounting heavy hardtops left these parts prone to structural cracks and deep scratches. Severe material pitting caused by moisture oxidation also led to permanent degradation that cannot be fixed by simple polishing. With New Old Stock (NOS) parts nearly extinct, traditional low-volume recasting is economically unviable. This scarcity left a critical gap in the classic car restoration market.
Reverse engineering and the industrial 3D printing process
To resurrect this part, the OctoClassic team combined historical craftsmanship with a highly disciplined digital workflow:
- Reverse Engineering: We 3D-scanned an original component to capture its exact geometric dimensions.
- CAD Optimization: The digital model was refined in CAD software to guarantee tight tolerances for a seamless OEM fit.
- Slicing: The digital model was sliced into microscopic 2D layers to map the laser’s path.
- LPBF Printing: Inside the MetalFAB system, a mechanism spread an ultra-thin layer of industrial metal powder, which the laser precisely melted. This cycle repeated thousands of times to build the rosette from the ground up.
- Thermal Post-Processing: The finished parts underwent precise heat treatment to eliminate internal stresses, ensuring structural strength comparable to forged or CNC-machined components.
Why we chose 316L stainless steel
Selecting the correct material was paramount to outperforming the original factory alloy. We selected 316L Stainless Steel (1.4404) for its exceptional properties:
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- Superior Hardness: It minimizes the risk of future scratches or dents during roof installation.
- Corrosion Resistance: It resists moisture and environmental exposure, preventing oxidation.
- Material Density: It provides an ideal, uniform base for high-end surface finishing.
By utilizing industrial-grade 316L stainless steel, we created an authentic OEM replacement part designed to outlast the vehicle itself.
Achieving the perfect mirror-finish
An industrial part cannot be placed directly onto a concours-level classic car without meticulous finishing. The raw, as-printed LPBF components feature a microscopic texture that would amplify imperfections if chromed immediately.
To achieve a flawless look, our team implemented a rigorous post-processing regimen. The parts underwent multi-stage vibratory finishing to smooth out the surface, followed by meticulous hand polishing. This specialized process yields a flawless mirror effect, capturing the timeless aesthetic of vintage chrome while retaining the physical integrity of modern industrial steel.
The future of automotive heritage restoration
This project proves that additive manufacturing is no longer just for rapid prototyping. It is a viable solution for producing end-use, industrial-strength parts for the luxury automotive market.
By combining reverse engineering, LPBF 3D printing, and master-level hand finishing, OctoClassic delivers components that meet the highest standards of automotive judges and collectors worldwide. We don’t just replicate rare parts; we re-engineer them to be stronger, tougher, and more resilient for the future.