Although principally associated with the aerospace industry, five-axis machining is now also being used extensively by auto and motorcycle racing teams. The benefits being sought are fundamentally the same—increased manufacturing flexibility and faster delivery of new or replacement components. While the cost of five-axis equipment has never been a problem for leading Formula One teams, falling prices for machines and the software that drives them have made this technology available to more companies involved in other areas of racing.
At the same time, new developments in machining software have made programming five-axis operations much easier. Delcam’s PowerMILL CAM system is one such product; it speeds day-to-day programming and cuts the time and cost of training. Furthermore, the wider availability of reasonably priced reliable simulation software has helped companies eliminate the cost of machining trials and reduce programming errors.
The major benefit of five-axis machining is the ability to machine complex shapes in a single setup. An obvious time saver, it also cuts down on the number of mistakes that might be made during multiple setups because there is always a possibility of incorrect alignment each time a part is moved.
The ability to machine much more of the component in a single setup means that human intervention is reduced. Add this capability to the increased confidence gained by performing simulations and overnight, unmanned machining becomes a real possibility—even for complex operations.
Another benefit of five-axis machining is that shorter cutting tools can be used since the head can be lowered toward the job and the cutter oriented toward the surface. As a result, higher cutting speeds can be achieved with no loss in accuracy. Adjusting the angle between the cutter and the part can also result in better surfaces, reducing time spent finishing.
The flexibility of five-axis machining can also remove design restrictions. For example, designers were previously asked to align holes along the same axis so they could be machined in the same setup. Drilling a series of holes with different compound angles on a three-axis machine is extremely time consuming because a different setup is needed for each hole. It is also easy to make a mistake when changing the part’s position in a long series of complicated setups.
Similarly, designers might be asked to avoid undercuts in their parts because more complex casting equipment is needed for their manufacture. With a five-axis machine, however, undercuts can be cut directly into the part, often without adding significantly to the overall machining time.
Two-Wheeled Five-Axis
For the Proton KR motorcycle team, the move into five-axis machining with Delcam’s PowerMILL software has realized three major benefits: more manufacturing work has been brought in-house; engineers have achieved more freedom to design; and most frame components can be machined from solid stock instead of being fabricated from sheet metal. Proton KR, which is owned and managed by motorcycling legend and triple World Champion Kenny Roberts, is the only independent team taking part in the current Moto Grand Prix (GP) series. Unlike the other teams, which race on motorcycles supplied by the major manufacturers, Proton KR develops its own unique racing designs at a manufacturing facility outside Banbury in the United Kingdom.
The Proton KR toolbox includes a new DMU50 eVolution five-axis machine from DMG. Andy Stokes, the team’s programmer and machine operator, admitted that it took a little time to take full advantage of the new machine. “With five-axis machining,” he says, “you have to look at the job a bit differently. You need to adjust your approach to fixturing and workholding to give access to the maximum number of features in each set-up.” Stokes goes on to explain, “Once you’re used to it, five-axis machining makes things easier, even for parts that could be made with our three-axis machine. We still can’t do larger parts and, with only one machine, we don’t have the capacity for longer runs of engine parts but, otherwise, we can now make everything in-house.”
The most important benefit of moving to a five-axis machine, says Stokes, has been the change from fabricating frame components to producing them from solid stock with a combination of wire cutting and five-axis machining. “Manufacturing from solid gives better structural integrity at lower weight than the equivalent fabricated parts,” he says. “With our new methods, we have reduced the weight of the bike by more than 15 kilos.”
An added benefit is consistency: “Previously, we always had to grind new parts to make them fit. Now, we can take spares off the shelf and know that they can be fixed straight onto the bike.” And there’s the possibility of even better results in the future. Team designers are changing the way they think. Where Stokes often had to ask for designs to be simplified so they could be manufactured on the old three-axis machine, now he can make almost anything that designers come up with.
Zytek Engineering
PowerMILL is also being used by Zytek Engineering—a specialist in automotive control systems, race engine design and development, powertrain development, and hybrid-electric vehicles—to build A1 Grand Prix series racing engines. This addition to the facilities at its manufacturing center in Repton Derbyshire, UK, is a result of a three-year contract to supply all the engines and electric gearshift systems for the new racing series scheduled to debut this September.
“For the new A1 Grand Prix series,” says Zytek Production Manager Ian Edmonds, “each team must have exactly the same engine so we will have to produce at least 40 identical examples. We realized that we would need to speed up our manufacturing techniques, especially the time we were taking to machine the engine ports, in order to produce these increased volumes.”
This is why the company had to introduce continuous five-axis machining. It already used positional five-axis techniques on some of its Mori Seiki machines, but the company’s CAM system was unable to produce continuous five-axis toolpaths. “We needed to look for an alternative,” says Edmonds.
In a multisystem investigation, PowerMILL won out. “PowerMILL is a genuine CAM system that is being developed constantly,” he says, “not just an add-on to a CAD software package.”
The biggest benefit expected from the addition of the Delcam software is in machining efficiency. “We are looking to reduce the time for finish machining of the engine ports by two-thirds,” says Edmonds. And early results show it’s an outcome within reach. “Even though we chose PowerMILL for its five-axis capabilities, we are also seeing some big improvements in the productivity of our three-axis machines,” adds Edmonds. “In fact, I may be forced to add a swarf conveyor to one of our three-axis machines because we are cutting metal so much more quickly.”
The Checkered Flag
As demands for faster delivery and higher productivity put the pressure on racing suppliers and other subcontractors to adopt five-axis machining methods, reliable, easy-to-use software will help them remain competitive. Fortunately, the continued development of such software will combine with market pressures to ensure that the overall cost of five-axis machines will continue to fall. The process will then make it easier for smaller companies to invest in new equipment and contribute to wider adoption of these techniques, both on the track and off.
Peter Dickin has worked at Delcam for more than 12 years. Previously, he spent 16 years at the plastics and rubber consultancy Rapra Technology in various management positions. You can send him an e-mail about this article c/o DE‘s Editors.
