052
AUTOMOTIVE & MOTORSPORT
How 3D printing makes McLaren go faster Since its founding by Bruce McLaren in 1963, McLaren Racing has relied on state-of-the-art manufacturing technology, so it was no surprise when it teamed up with Stratasys to push its use of additive manufacturing (AM) to the next level. The competitive nature of Formula 1 (F1) racing pushes teams to develop the best solutions possible in their quest to reach the winner’s circle. Using tools like AM, F1 racing has become an inspiration to other enterprises on how to maintain the lead in their own industry. In F1, every gram of weight is critical. But simply cutting weight is not the only thing the McLaren team has to watch out for. The safety of the driver is of utmost importance as well. For this reason, it’s crucial for engineers to ensure they are meticulous in their approach regarding how loadbearing features of the car’s suspension are bonded together. Too much adhesive and the car will be slower, giving the other teams a chance to pull ahead. Too little adhesive is not an option either. In one clever example, McLaren printed clear surrogate suspension parts to practice the bonding process. The clear material lets technicians see how the adhesive spreads when parts are pressed together and provides visibility to the integrity of the bond joint – something that’s not possible with opaque materials. They can refine the technique with the right amount of adhesive, safeguarding against an insufficient amount but also eliminating excess weight. By taking advantage of the VeroUltraClear material on the Stratasys J850 PolyJet printer, McLaren successfully used transparent 3D-printed test parts to ensure their bonding processes are accurate before the final components
AMT DEC 2021
enter production. Using AM for innovative solutions like this helps McLaren finetune manufacturing processes, reducing costs. “This tool allows us to quickly verify the bonding process integrity between a composite suspension wishbone and its mating metal end fitting,” says Neil Oatley, Design & Development Director at McLaren. “Using AM, rather than machining metal or polymer, allows us to achieve a component quickly with less personnel involved. Less time, fewer people, less material, less wastage.” The J850 printer enables McLaren to create high-resolution wind tunnel models for aerodynamic research. The technical team uses them to make small mechanical adjustments to prototyped parts. This results in a race-ready car faster than testing iterations on full production vehicle components. Using PolyJet technology gives McLaren the ability to reduce time from initial design to physical part, and offers something other technologies cannot – flexible, durable parts. The flexibility of certain PolyJet materials allows the team to make small mechanical adjustments in the wind tunnel to find ideal solutions without having to rebuild the parts. Using GrabCAD Print software, engineers can vary the stiffness of different regions of the model. This adjustability reduces time spent producing and finishing parts for the wind tunnel and allows more time for designing and testing. “Speed is as crucial off the track as it is on the track,” says Piers Thynne, Executive
Director – Operations at McLaren Racing. “An F1 car is made up of around 16,000 parts and on average, one part is upgraded every 15 minutes, so speed of production is really key. From the traditional first race of the season in Australia to the final race in Abu Dhabi, we expect 85% of the designed parts of the car to change. It is a constant race against time not only on the track but in the factory too.”
Printing production parts Like other race teams, McLaren uses composites for aerodynamic parts of their racecars because they’re lightweight but strong. In some cases, however, there isn’t time to fabricate these parts due to the hours required to make new lay-up tools and cure the composite material. The need for alternative parts that are light but strong and stiff led McLaren to employ 3D printing instead, using FDM Nylon 12CF material. This composite thermoplastic contains chopped carbonfibre, resulting in parts with exceptional strength and rigidity. Although traditional composites may result in a lighter part in some cases, the time savings afforded by 3D printing makes the extra weight worth it. In one example, McLaren was able to go from CAD model to physical part in just five days, for a task that previously took 29 days. Instead of racing with inadequate parts on their car for numerous races, engineers were able to have optimised 3D-printed parts on the vehicle for the next week’s race. 3D printing saved approximately 25% in cost compared with
