Creating New Opportunities

Left to Right: Bob Burns, David Burns, Judy Burns, Julia Burns

"We invest to innovate, be challenged, and open windows of opportunity that did not previously exist," says Bob Burns, vice president and cofounder, Patriot Machine Inc. "As one of the first companies to invest in large 5-axis aluminum machining capabilities, we established ourselves as true innovators in aerospace manufacturing. We are continually investing and engineering new ways to improve our efficiency, all to supply what matters most to our customers: quality parts delivered on time."

Impossible is a word not commonly used at Patriot Machine of St. Charles, MO, a world-class manufacturer of complex aerospace parts and assemblies. Patriot has built its business on successfully completing the most difficult manufacturing challenges through innovative process solutions and machining technologies. As an added service to original equipment manufacturers, Patriot collaborates with design engineers to optimize part designs, improving manufacturing efficiency.

Patriot cemented its reputation with the addition of new and advanced titanium machining capabilities. Judy Burns, president and cofounder of Patriot Machine, recognized the importance of expanding with differentiating equipment. After thorough analysis, Bob and Judy decided to purchase two Makino 6-axis horizontal machining centers coupled with a 32-pallet automated material-handling system, as well as one Makino T4 5-axis horizontal machining center.

“Aircraft manufacturers will be amazed by what we are now able to accomplish in titanium,” Bob says. “The T2s have eliminated limitations our industry experiences with traditional equipment, slashing cycle times, and allowing for reduced-setup machining, thinner and lighter part designs, extended tool reach, and unlimited part angularity. We are seeing value-added benefits, such as longer tool life, which we believe can more than quadruple with additional research and process refinements. But right now, we are working to inform OEMs of the T2’s capabilities, opening new opportunities for them to pursue greater complexity in their part designs.”

An Eye for Innovation
Incorporated in 1991 by Judy and Bob Burns, Patriot initially opened for business as a CAD/CAM services company. At the time, CAD/CAM was a new and developing technology, but the husband-and-wife team saw the potential to push the envelope for complex part designs.

“Early CAD/CAM technology was far from perfect, and initially, some simple designs required more time to complete than drafting by hand; however, its true capabilities were discovered in more complex 3D designs,” Bob explains. “It was really the inevitable growth in design complexity that pushed the need for CAD/CAM. When you think about the parts produced today, there really is no way these designs could be accomplished by hand.

“You do not grow a business by focusing on jobs that come easy to you. You have to take on the complex jobs that push your team to develop new and better processes. We started this business out of our garage, and today, we are working in an 82,000ft² facility, employing more than 130 talented individuals. This growth could not have been possible without overcoming some difficult challenges and having the foresight to invest in the most capable aerospace machining equipment. With this equipment and our technological know-how, our customers believed in us, giving us a chance.”

Changing the Aerospace Landscape
Aerospace manufacturers have been producing aluminum parts for decades; however, with recent advancements in machine capabilities, the complexity of these parts has grown exponentially. Patriot was able to gain a leg up on the competition during this dynamic transition period by making early investments in large 5-axis aluminum machining capabilities.

Patriot’s early investments in Makino’s MAG3 5-axis horizontal machining centers enabled the company to evolve part designs from simple assemblies to complex monolithic structures.

“Whenever you can take an assembly and reconfigure it into a single monolithic design, you are not only improving manufacturing efficiency but also reducing part weight and cutting costs throughout the supply chain. Key benefits include fewer parts to be purchased, managed, produced, and stored,” Bob says. “When Makino released its MAG3 5-axis horizontal machining center, we immediately recognized its potential for producing more complex features in a single setup. This enabled us to gradually evolve from simple assembly designs to complex monolithic structures while establishing ourselves as the go-to resource for customers interested in making this transition.”

One example of this capability was a variable-inlet application that originally required 96 individual components. Because of cost-cutting initiatives, the customers approached Patriot with the challenge of manufacturing their newly designed monolithic components. Patriot viewed this request as an opportunity to demonstrate how the MAG3’s capability of machining complex contours and closed-angle features.

Due to the success of its initial investment in 2004 of a MAG3 and an 8-pallet automated material-handling system, Patriot has since expanded its aluminum machining capacity by adding a second MAG3H – the pallet system is able to feed both machines.

Bob and Judy attest that the evolution of their company has experienced a unique learning experience with aluminum part designs, preparing Patriot for similar experiences in hard-metal part designs.

Improving Titanium Machining Efficiency
Over the last decade, aerospace industry demands for higher fuel efficiency have led many aircraft manufacturers to use more titanium in aircraft designs. Previously, Patriot produced titanium parts on 5-axis vertical machining centers; however, Bob says, operators and engineers experienced a variety of limitations when developing processes for some of the newer part designs.

“There is nothing more frustrating than designing the perfect process and then having to scale it back due to machine limitations,” Bob states. “You can plan processes to work around issues, but in the end you’re still hindered from reaching your full potential. We decided to invest in the next level of technology to remove these limitations.”

Patriot evaluated a variety of machine technologies and processes, including gantries and cryogenic machining. Based on its previous experiences with Makino’s MAG3 machines, the company decided to learn more about Makino’s T4 5-axis horizontal machining center and T2 6-axis horizontal machining center.

According to Patriot employees, the T2 combined with ADVANTiGE capabilities have enabled engineers to employ cutter lengths of up to 23.6" for increased feature access.

“Where most other machine tool manufacturers made slight modifications to existing products and marketed them as titanium machining centers, the T-Series machines were the first built specifically for titanium machining of aerospace components,” Bob says. “Makino got the basics right from the very beginning, looking at what was most important, including proper cooling, vibration damping, and sufficient spindle power and torque. Every aspect of the machines demonstrated that Makino clearly understood the challenges our industry was experiencing.”

A primary component of Makino’s T-Series machining centers is its ADVANTiGE technology, a set of key machine features Makino developed to counteract the traditional limitations of low metal-removal rates and limited tool life in titanium machining. These features include a high-power, high-torque tilting spindle, Collision Safe Guard and Autonomic Spindle Technologies, high-pressure, high-flow coolant system, vibration damping system, and a rigid machine construction.

Bob describes ADVANTiGE technology as the secret ingredient that ties everything together. While the company specifically likes the coolant system, vibration damping, high-capacity automatic tool changer, and HSK-125A spindle interface, it is the complete harmony of all ADVANTiGE technology features that enables Patriot employees to reduce cycle times and improve the overall quality of its complex stainless steel and titanium parts.

“The very first set of parts we produced on our T2s was for a hard-metal assembly, which we won in a global competition. Machining of the four titanium parts consumes less of the available tolerance than traditional machines are capable of holding. When the very first four parts were assembled, we found that the assembly consumed only one-fourth of the available tolerance,” Bob explains. “The ability to consistently produce part features to tighter tolerances will not only help OEMs achieve tighter assembly tolerances, but will also allow thinner designs for features such as flanges, stiffeners, and ribs. Ultimately, this level of capability will enable OEMs to significantly reduce the overall weight of aircraft for improved fuel efficiency.”

Adapting to New Opportunities
For the highly skilled engineers at Patriot, the T-Series machines represent an opportunity to work together to develop new techniques and manufacturing methods that few in the industry thought possible.

“In a way, we feel like the pioneers of titanium machining all over again,” says Paul Rosner, Patriot’s technical operations and tool applications engineer. “The improved spindle, rigidity, vibration damping, coolant delivery, and part accessibility of these machines have completely changed the way we engineer our processes. The spindle manipulation, indexable pallet, and tooling options enable us to reach more complex features and apply more aggressive cutting techniques.”

Rosner details the T-Series spindle design as a flexible powerhouse due to the improved tool-gripping rigidity, 21,000 lb of retention force of its HSK-125 interface, and 1,100ft/lb of torque. The rigid HSK-125 holder and retention force enables Patriot to eliminate previous stack-up inaccuracies, deflection, and fretting of the holder.

“Now a 23.6" tool runs as smoothly as an 8" tool,” Rosner says. “We are seeing little to no hesitation in our toolpaths, even when roughing with full, simultaneous-axis motion. And while the T-series spindle design provides just more power than our previous spindles, the torque curve allows us up to four times the cutting speed.”

Rosner reaffirms that this level of capability is dependent on other features of ADVANTiGE, emphasizing the importance of the coolant system capacity, as well as the machine and spindle rigidity for enhanced tool life.

“When it comes to titanium machining, coolant delivery is critical; without enough coolant supply, a machine can burn up a tool within 20 seconds,” Rosner notes. “The T2 and T4 have alleviated these concerns with a robust coolant system that includes through-spindle delivery. With a steady flow of 53 gallons per minute at 1,000psi through the spindle, chips and heat from the cutting zone are effectively displaced, providing us with noticeable improvements in tool life. As we continue to refine our processes, we anticipate even greater tool longevity.”

Patriot illustrates the effectiveness of the combined ADVANTiGE capabilities through a titanium pivot hub component that featured four holes located on a vertical sidewall, just inches above a horizontal plane approximately 20" in length. According to Rosner, the difficult-to-reach hole locations could not have been machined using previous equipment; however, the T2’s rigid spindle and robust coolant options enabled engineers to reach across the horizontal surface with a 23.6" tool, only thousandths of an inch from the part floor.

“Even the most complex features can be manufactured in a single setup. In the past, this required multiple setups and custom fixtures,” Rosner states.

Getting More Out of Every Setup
Walter Burns, Bob’s brother and Patriot’s manufacturing engineering manager, asserts that some of the biggest benefits to productivity have been increased part access and tool capacity.

“The more rotational motion a contoured or multi-sided part requires, the more the T2 outperforms,” Walter says.

One contract that Patriot recently won, in part because of the T2’s capabilities, was a part requiring ±45° of tool rotation. Using previous machinery, the job would have required five setups and multiple fixtures; however, the 6-axis capabilities of the T2 with its unlimited B- and C-axis rotation lets the company combine four setups into one, completing the part with improved accuracy.

The T2’s spindle manipulation, indexable pallet and tooling options enable Patriot to reach more complex features and apply more aggressive cutting techniques

“Our throughput capabilities for complex stainless steel and titanium applications are some of the most competitive in the industry, and they only stand to improve with our recent investment in a 32-pallet automated material-handling system. We will not have to tear down and set up our fixtures for recurring production. We will leave the fixtures set up on the work cubes and cycle them as needed, allowing for single-piece flow and no setup cost on complex parts,” says Walter.

With the increase in available throughput, Walter notes the elevated importance of the T2’s optional 192-tool-capacity automatic tool changer, explaining that in order to ensure maximum utilization rates while minimizing labor, the company opted for the largest magazine available.

“A typical application is programmed with about 40 tools, while 90% of these tools are shared between jobs, it is to our benefit to have additional capacity for the tools that are different from part to part and for more complex parts in the future,” Walter says.

Leading the Titanium Market
According to the Burns family, confidence is the most important benefit of the Makino machines.

“It is a great time to be in aerospace manufacturing, and we are excited about the future,” Bob says. “Whether a job calls for aluminum, titanium, or stainless steels, we have the capabilities to complete complex jobs – winning with tighter tolerances, lower cycle times, and overall best value per part than ever before.”

Bob notes several plans for expansion following the completed installation of its new automated material-handling system.

“As awareness of our new hard-metal manufacturing capabilities continues to grow, we are looking at two additional T2s to complete the cell. Our T4 is arriving this fall to take on applications up to 4m in length, and we have expectations of a second T4 in the future,” Bob explains.

“Makino tackled the challenges of titanium head on. Their engineers took a step back and reevaluated the machining process from the ground up to ultimately provide an effective solution. Most aerospace manufacturers have yet to realize the full capabilities of the T-Series and ADVANTiGE technology. But when they do, it is guaranteed to change the way titanium and other hard-metal components are designed and manufactured.”

Patriot Machine Inc.
St. Charles, MO
www.patriotmachine.com

Makino
Mason, OH
www.makino.com