12 April 2017 13:09
Expert Interview: Renault Formula One Team’s Additive Manufacturing Specialist Pat Warner
Pat Warner is ADM Manager at Renault Sport Formula One Team — an in-house additive manufacturing specialist, working to deliver first-class printed components for both prototyping and production purposes. Having been deeply involved in additive manufacturing within F1 for more than 19 years, Pat has witnessed a number of key developments in the technology and its applications, which he was kind enough to discuss with AMFG in the interview below:
AMFG: How did you originally become involved in additive manufacturing?
Pat: I was originally a CNC machinist with the then Benetton Formula Team and moved into the CAM department in 1997. We bought our first SLA machine in ‘98, but didn’t really know what to do with it. The machine was placed into a room adjacent to the machine shop and the task of programming given to the CAM group. By 2000, we’d found enough applications to PX the SLA machine for two newer, faster models. By 2002, we bought two more. In 2003, we added laser sintering to the department and have gradually expanded ever since to the existing department of nine machines.
AMFG: What have been some of the greatest AM success stories you’ve witnessed during your time at Renault?
Pat: There have been so many over the years.
We prototype every new component of the car and assemble it for function/fit. This is nothing new in the world of additive, but means we get to find our mistakes very quickly. The packaging on a modern F1 car is a challenge for the design team, as allowing space for the mechanics to access parts of the car is a difficult thing to achieve looking at a screen.
We manufacture our own investment casting patterns for our structural titanium components, such as the gearbox casing. We’ve put a lot of time and effort into refining this process and usually end up with the foundry we are using requesting to purchase patterns from us (at this point we only make components for the team).
Additive manufacturing has without doubt increased the rate of development in F1’s wind tunnels. When we were running unrestricted wind tunnel hours, we would produce in excess of 600 parts a week, just to feed the tunnel. The amount of conventional manufacturing resources required to achieve the same target would be immense.
Rapid jigs and fixtures have helped with the production of the car and with last-minute modifications at the circuit. Finding an issue on the Friday, making replacement items and delivering them to the track in time to be fitted for qualifying has happened on many occasions.
Of course, we’ve had our little disasters as well, but they all help with the learning process.
AMFG: What are the key challenges you have experienced when it comes to AM as a tool for both prototyping and production?
Pat: Again, there have been so many.
When we first started with it, longevity of the part was a huge issue, SLA materials were very fragile and didn’t take well to humidity. If you could keep a part on your desk for a week without someone breaking it, it would distort as it absorbed moisture from the air. Material development has taken care of these issues and made some vast improvements along the way.
As we started to buy in components from outside suppliers, we found you would rarely get the same part twice, even if it came from the same build, in some cases. This encouraged us to bring more in-house, spending more time understanding the equipment and materials and refining our processes. In 2004, we partnered with Boeing. This partnership helped us both along that road and has led to us being able to put more components on our vehicles. We have developed materials specifically for our needs, which are commercially available (FIA regulations dictate they must be) and are being used elsewhere.
Education has also been a challenge, although the technology has been around for quite some time now, its adoption into mainstream manufacturing has been gradual, as has education. As a result of this, we still get new designers that have had no exposure to additive manufacturing.
AMFG: What new innovations would you most like to see in terms of both printing platforms and materials?
Pat: Both areas have come on a long way in the 19 years I’ve been involved, but there is still further scope for the technology to mature. We still need to pay a lot of attention to our processes to achieve the results we require and we still see inconsistencies in some of the components we buy in. Some of these inconsistencies could be in the equipment we use but good steps have been recently made in this area, some are in the way the suppliers use said equipment and recycle the materials. It’s not all about the platforms and materials though; we also need better design tools for AM.
We’ve all seen the lightweight hollow structures with latticework on the inside. This should be perfect for motorsport and aerospace, but in reality, we are not able to predict strength, stiffness and failure mechanisms of such components well enough to be able to utilise them to their full potential.
AMFG: How do you see the use of AM evolving within F1 in the next few years?
Pat: We’re finding new applications all the time. As the size of the toolbox increases further, so will the number of applications.
Metals are taking huge steps every year, as are high temperature polymers. As they advance further and we better understand how to use them, we’ll be able to get much more from AM parts.
It’s quite an exciting time for AM, it’s gaining a lot of attention and funding. This can only be good for the entire industry, as there is still some way to go before we can fully challenge conventional manufacturing.