Last month, I accepted an invitation from Pat Warner, the ADM manager for Renault Sport Formula One Team, to visit its additive manufacturing (AM) facility in Enstone, Oxfordshire, UK. The invitation came following an online discussion Pat and I had as the result of my feature for Disruptive Insight on the reality of post processing and ancillary equipment required for industrial AM applications. Pat is a long-time AM industry veteran and our paths have crossed many times over the years; I have always found his insight and opinions as a super-user of AM technology to be valuable.
The opportunity to take a day, catch up with Pat in person and get a tour of a Formula 1 factory was not to be passed up. Moreover, the reality check that comes from visiting a real manufacturing facility is always worthwhile. While it can be argued that a Formula 1 constructor does not fall under the typical definitions of a manufacturer, because it has very different priorities and motivation to, say, its road car peers, it is nonetheless driven by factors that resonate with any manufacturing environment. There is also an argument that in some respects it is even more demanding.
Globally, Renault is an automotive giant and has had a solid 115-year relationship with motorsports in general, while its specific relationship with Formula 1 has been somewhat more off and on again. Right now, the Formula 1 commitment is stronger than it has ever been with significant investment being made in the Enstone facility to expand and upgrade it considerably. One of the first things to come into view, approaching the facility, nestled in the Oxfordshire countryside, was a huge crane (with a strict no photographs policy on site, you’ll just have to take my word for it though). Pat told me that the footprint of the expanded site will be about 30 percent bigger when completed.
It’s no secret that Formula 1 teams were among the earliest adopters of additive technologies, using them prolifically for rapid prototyping applications in the 1990s and early 2000s to speed up product development times. They were also quick to jump on the rapid tooling capabilities of AM as processes and materials improved. Today, an increasing number of additive manufactured parts are being placed directly in the race cars. Renault Sport Formula One Team’s history with additive technology follows a similar trajectory and is the result of a long-term and ongoing partnership with 3D Systems. Pat currently manages an impressive AM department in Enstone, housing a suite of stereolithography (SLA) and plastic selective laser sintering (SLS) machines.
For historical perspective, he told me: ‘We bought our first SLA 5000 in 1998, [but] had no real idea how we were going to use it. That didn’t last long. As we started to understand what it could do, working with dedicated application engineers from 3D Systems, its value in proving or disproving concepts and reducing development time became essential to the workflow. We also pushed the boundaries as we came up with new applications. By 2000 we had outgrown it, so we traded it in for two, faster SLA 7000s and started producing wind tunnel models. Then in 2002 we acquired two more, as well as an Optoform system. In 2003, we added two SLS machines. In 2005, we returned the Optoform and added a Sinterstation Pro as well as another SLA 7000. Then, in 2010 we increased the size of our wind tunnel model, so traded in four of the 7000s for five 8000s. And last year we upgraded the sintering machines.’
Machines and materials
Thus today, the facility is running six SLA machines and three SLS machines in-house for a range of prototyping, aerodynamic wind tunnel models and production applications for the track car.
In terms of the evolution of the applications, Pat attributes this to the development of improved, highly functional materials for both SLA and SLS processes. All new materials undergo extensive testing, to achieve repeatable mechanical properties and the necessary confidence to put AM parts on the car. Of note here is the high-performance ceramic (HPC) filled resin, which is the latest SLA material, specifically requested of 3D Systems by Renault Sport Formula One Team. For the SLS process, carbon filled nylon powder has been a priority development, with a view to improving the strength and temperature resistance of parts.
The years of development work in partnership with Boeing (a relationship that started in 2004) are now producing results, and the SLS machines at Renault Sport Formula One Team frequently produce end-use parts built with the encapsulated carbon fiber nylon material. It is a very specific formulation that mixes the carbon fibers within the polymer in such a way that each spherical particle has fibers embedded in it. Thus, when the material is rolled out, the demonstrable and extensively tested result is an isotropic orientation of the fibers, with the vastly improved mechanical and modulus properties as well as greatly increased temperature deflection capabilities desired for demanding aero and F1 applications.
With the catalyst for this visit being the post-processing debate, it didn’t take long for the conversation to turn to this topic. Pat showed me the equipment that they use in their facility and, unsurprisingly, it took up almost as much floor space as the additive machines themselves. One specific example that Pat highlighted was the washing equipment for parts off the SLA machine. He explained: ‘Equipment is available on the market, specifically branded for post-processing SLA parts quickly and efficiently. After assessing our requirements and the standard equipment commercially available—at a premium—I looked for an alternative solution. I talked with a local firm knowledgeable in de-greasing and ordered a bespoke solution that achieves high-quality results for considerably less (60 percent) than the off-the-shelf ancillary equipment would have cost.’ This illustrates that the costs involved in post-processing can be reduced, but the time and effort involved in converting the parts off the machine in to the ‘finished’ part remains a considerable, often ignored, part of the process.
It’s not all about the hardware, however. For all additive parts, both plastic and metal, the design stages of the manufacturing process are an essential part of post-processing at Renault Sport Formula One Team. As Pat said: ‘We can minimize the post-processing considerably at this point by designing the part in the right way—for the process. In real terms, we can save hours of post-processing by understanding the materials we are working with, how they will be built and how they will come off the machine.’
Moreover, Renault Sport Formula One Team are not constrained to only the SLA and SLS additive processes. They also contract out a significant number of parts to service bureaus, most notably metal parts, which are increasing in number.
Overall my day at Renault Sport Formula One Team highlighted some real progress with additive technologies as evidenced by the rate at which the number of AM parts on the car continues to increase, but also, most strikingly, by Pat’s revelation that part of the expansion and upgrade of the AM department will see the team investing in a metal system. He told me that they were now at the ‘tipping point’, where it made commercial sense to bring a metal AM machine in-house. The significance of this cannot be overstated, actually.
But while the progress is encouraging to say the least, challenges remain. Perhaps the most striking, from Renault Sport Formula One Team’s point of view, is that Pat relayed how a high number of parts have been identified that would benefit from design optimization and production via AM (in terms of weight and performance). However, there remains a high degree of reticence for many of them, specifically the most critical of critical components, because of the reliability issues with metal AM.
I drove the 200-mile journey home grateful for such a good day with good people, the opportunity to see real progress with AM in action and talk, realistically, about some of the challenges still to be overcome … as well as, of course, preparing to cheer on Jolyon in the Hungarian Grand Prix!