Five-axis machine tools represented a major advancement over earlier machines, with greater range of movement and the ability to create more complex shapes. Now, with increased automation and greater tool capacity, five-axis machines are becoming more productive than before.
Five-axis development has been going on for the past 15 years, executives said. That development has been assisted by advances in software and customers’ growing capability to create their own five-axis machine programs. Also, they said, processing speeds are faster and five-axis work is spreading from automotive parts to more complex and high-end aerospace components. Automation is seen as a way for manufacturers to get the most out of their five-axis machines.
“The need to justify the ROI on expensive five-axis machines is another factor leading towards the desire to increase automation,” said Fred Puzon, national sales manager for milling at MC Machinery Systems Inc. (Elk Grove Village, IL). “Lack of a skilled labor force has driven manufacturers to find more ways to automate the process.”
New applications are also powering this trend. “More and more things are being driven to one setup,” said Joe Wilker, product group manager for Mazak Corp. (Florence, KY). “We never had gear applications before. Now gear applications are common on five-axis multitasking machines. Manufacturing continues to push the technology to new levels.”
More shops are using lights-out machining, which typically requires sophisticated automation. “There are compelling reasons to automate, especially for consistent throughput and added production capacity on off-shifts,” said Marlow Knabach, chief technical officer for DMG Mori USA (Hoffman Estates, IL). “Automation can facilitate increased efficiencies of personnel.”
For example, he said operations such as deburring, washing, and palletizing can be automated. “Eliminating these types of non-value-added tasks from the [machine] operators has the potential of concentrating efforts to decision-based operations that the operators can be trained to if the skills did not previously exist.”
The evolution of five-axis machines coincides with the broader advancement of Industry 4.0, with connected machines managed via smartphones and tablet computers. Industry 4.0 is requiring better trained workers who oversee multiple machines.
“Your employees must understand the complexity and programming of automation,” Puzon said. “So we as a manufacturer need to better train the customers and workforce on operations.”
What follows are how companies view changes in five-axis machines.
The automotive industry pushed automation of five-axis machining, some executives said. Automotive requires mass output of parts and vehicles compared with other industries. Now, the automation used in five-axis machining auto parts is migrating to industries such as aerospace and oil and gas.
Five-axis machines are also adjusting to Industry 4.0. Data from machines helps to determine when maintenance occurs and to maintain production and reduce downtime.
Mazak is a company where Industry 4.0 is a factor. The company has what it calls its iSmart factory concept.
“[Industry] 4.0 definitely is helping out in the iSmart factory,” Wilker said. “You’re not making a dime unless you’re making a chip. We call it iSmart … Being able to collect data from all this equipment we have” assists the effort, he said.
“This equipment is not cheap,” he added. “You have to make it run.”
Mazak also sees its role as helping customers adjust to increased automation. “Our operators are going to have to be smarter by far,” Wilker said. “They’re tasked with doing more with one machine. As a manufacturer, we’re trying to make that as easy as possible.”
Mazak has embraced the notion of multitasking and turned it into a guiding philosophy. In the Mazak world, multitasking is combining cutting processes “including turning, milling, drilling, tapping, and deep-hole boring on one machine as opposed to having those same processes handled by multiple machines,” according to its website.
Additive manufacturing, where parts are printed layer by layer from a digital design, is being incorporated with traditional subtractive machining in hybrid machines. For example, Mazak has developed a system that uses both direct metal laser sintering and subtractive machining. According to the company, such systems build “features onto existing parts then machine them to finished size.”
“That’s what we call ultra-tasking,” Wilker said. The 2018 IMTS show in Chicago will see “hybrid additive/subtraction manufacturing reach a new level on five-axis multitasking machines,” he added.
DMG Mori provides “multiple variations of automation, including pallet systems,” Knabach said. “Pallet systems allow multiple parts to remain set up and facilitates ship-sets to be easily managed, even with complex assemblies.” The company has also worked to make programming and operations easier, he said.
The company’s CELOS control platform “enables the functionality of the machine operator and delivers relevant information to the operator,” the executive said. “New part numbers can be created as jobs, including CNC programs, setup documentation, tool list, etc., and repeat orders can be processed with a simple update.”
Knabach said DMG Mori’s condition analyzer and performance monitor “provide data management and operation visibility to leverage the technology and ensure optimum machine availability. This minimizes the time required to realize a return on investment.”
Five-axis machining, he continued, “often times is associated with complex part configurations, many of which require a significant number of tools. Managing a complete tool library, including tool offsets and tool life, can be easily accomplished with CELOS and supporting options.”
At MC Machinery, training is emphasized. “There is a huge shortage in skilled labor,” Puzon said. “So the workforce you have must be trained on many levels.”
The company said its machines have features intended to improve output and quality. “Features like center point management will help compensate for the offset on the tool, which ensures the accuracy of the contour,” he said. That takes place on a 19″ touch screen “which lends itself to easier operation.”
Also, Puzon said, “A very large key to a successful five-axis [machine operation] is a qualifying process. The initial part must be qualified to avoid interference or re-clamping so that you can perform your five-axis work without any issues.”
The evolution of five-axis machines also affects tooling.
BIG Kaiser Precision Tooling Inc. (Hoffman Estates, IL) advises customers after they have bought a machine from a builder. “If they are that rare bird that does take tooling into consideration before, during or with the machine purchase, then we offer them the same assistance,” said John Zaya, product manager-workholding for BIG Kaiser.
“Buying tooling after the machine is only beneficial if they don’t know what their final requirements are going to be,” he continued. “In which case, we advise the using of tooling certificates … as they grow into the machine and the work requirements.”
According to Zaya, “The primary considerations when looking at tooling during the transition to a five-axis machine are reach, clearance, and balance.
“In three-axis machines, the toolholders are commonly as short as possible with as large of an outside body diameter allowable to make them as rigid as possible. This is done to maintain a high material removal rate, which is a key measure of the performance of the machine, the toolholder, the cutting tool, etc.”
Among the items to consider: “Toolholder balance, while important in any type of machine can become very critical in a five-axis machine that is being used to do ‘full five-axis work’ generating complex surface geometries,” he said. “The cutting edge of the end mill must be consistently engaged with the material in order to prevent chatter and poor surface finish quality.”Zaya said holder types such as slim nose collet chucks, slim type hydraulic holders and slim type shrink-fit holders are designed from the ground up to provide as much reach, clearance and balance as possible.”
What’s more, he said that “completely eliminating the holder is an option as more cutting tool manufacturers are providing integral taper cutting tools.” Such tools “interface directly with the machine spindle, thus eliminating many of the unwanted side effects of a holder with all the benefits of the machine spindle and its structural stability.”
Manufacturers may need to take a second look at tooling requirements when using five-axis machining. “Most often, tooling should be re-evaluated with five-axis machining,” said Tyler Martin, manager-technical services for Seco Tools LLC (Troy, MI).
“Many conventional three-axis operations can use short toolholders with short tool stick-outs, but five-axis machines give users the ability to reach more sides of the part, thus increasing the need for longer tool reaches,” he continued. “The need for interference and reach checking increases for five-axis machines.”
In addition, he said, “Part shapes and fixture strength usually dictate that tools that generate less axial and radial force are used in five-axis machining. In many cases, fixturing and parts need to be located a good distance off the table and tools must be able to perform well under somewhat unstable conditions.”