Mécaprec, a company that occupies an important position in the aerospace industry, conducted cutting tests on Mitsubishi Materials Corporation's (MMC) VFX corn end mill equipped with indexable inserts in order to improve processing efficiency. The test results showed that processing nickel-based alloys ( Inconel 718) part machining time is reduced to a quarter of conventional machining time.

The pursuit of excellence - this can be said to be the motto of Mécaprec, and it is also the concept that small and medium-sized enterprises focusing on precision machining have always adhered to. At least that's the goal Mécaprec has set for itself, and we can see it hanging in capital letters on the blackboard in the workshop. In addition to individual indicators such as "on-time delivery" or "proportion of substandard products", colorful emoticon tiles can also be seen on the shop floor. They provide an overview of the plant's performance during the current week and the past month, as well as trends for future work. “Seeing these emoticon tiles, everyone can immediately know our current progress,” explains Mr. Jean-Marc Gomez, the boss of Mécaprec. “They are easier to understand than graphs.” In “Customer Feedback” "This indicator has a green smile sticker next to it. “We only sell to the customer something that fully meets his expectations,” Mr. Gomez emphasizes.

Tackle future machining tasks with automation

In order to meet the requirements of the aerospace industry, which accounts for 98% of the company's turnover, Mr. Gomez did not hesitate to expand the company's premises, acquire production equipment and invest in automation technology. An articulated robot equipped with 21 pallet positions and fully integrated into Computer Aided Production Management (CAPM) will be complemented by another robot capable of operating 58 pallet positions. There will be a third industrial robot of this type in the factory after October. "In the future this system will be called an independent processing island equipped with industrial robots."

Mr. Gomez officially took over Mécaprec in 2008. At that time, the entire company had only 12 employees and a turnover of approximately 800,000 euros. The company is based in Lavelanet, in the Ariège department of France, an area once famous for its textile industry and from which Mr. Gomez is also from. Today, seven years later, the company has 50 employees and its turnover has increased 6.5 times compared with the original amount. Everything is always difficult at the beginning. Just three months after taking over the company, the global economic crisis hit. “Fortunately, Aubert et Duval gave us a lot of trust,” recalls Mr. Gomez, “and we were able to start production.” It took Mécaprec thirteen months to obtain EN9100 certification. A dedicated aviation industry quality management standard. Since then, almost all parts produced at the Mécaprec factory have become best-sellers used on Airbus A320, A350 and even A400M transport aircraft as well as aircraft manufactured by ATR.

When high temperature resistant materials meet corn milling cutters

However, at the end of 2014, Mr. Gomez and his team got into trouble during a process - it took eight hours to process a nickel-based alloy part on the A320 Neo aircraft, which put profitability at risk. "This would mean that it would take a week to machine an assembly of four or five parts - it is simply unimaginable." In addition, the indexable inserts had to be inspected frequently, and since the cutting edge was only designed to last for two hours, Mr. Gomez decided to look for other tooling solutions.

“At first, we were skeptical about using corn end mills to process nickel-based alloy parts,” said Paul Bermes, a young engineering bachelor who graduated from the Icam Engineering School in Toulouse and has been working at Mécaprec for a year and a half. In the end, the team decided to choose the VFX series corn end mill from Mitsubishi Materials Corporation. A few months ago, Mr. Laurent Le Méteil, the regional manager of Mitsubishi Materials Group's French subsidiary, gave a report on cutting tools, which sparked Mécaprec's interest in this type of milling cutter. In addition, since Mr. Méteil took over as the head of the Southwest France region in May 2014, close communication between him and Mécaprec has rapidly developed, which also played a very important role. “I arrived at Mécaprec one month before we started testing so that we could determine the cutting speed and depth of cut together with the employees,” Laurent Le Méteil told us. Then the first round of testing began, and surprises followed. “During the first round of testing I looked at the spindle... there was no pressure build-up; everything looked fine,” said Mr. Paul Bermes. The parts were perfectly machined after just two hours. "I also ordered a considerable number of MP9000 new series of indexable inserts from Mitsubishi Materials on the same day, ready to be used to process high-temperature-resistant materials."

Subsequent tests were all satisfactory. “It can be seen that this corn end mill is specially designed to withstand the cutting forces generated when machining high-temperature materials,” explains Mr. Méteil. “This is a milling cutter that is 100% suitable for milling high-temperature alloy materials such as titanium alloys or nickel-based alloys,” he continued. By using this milling cutter, Mécaprec was finally able to reduce the machining time from eight hours to just two hours.

The enlightenment brought by one success

Mitsubishi VFX indexable milling cutter's convex arc-shaped cutting edge and V-shaped bearing surface enable precise and high-quality machining. In addition, the main cutting forces are borne by the thickness of the vertically positioned indexable insert, so the insert can achieve a high level of rigidity. In addition, ideally rolled chips can be well discharged through the cutting fluid. The nozzles of cutting fluid and coolant are placed close to the cutting edge, so that the chips can be directly controlled. Through this simple chip removal method, contact between the chips and the cutting edge is avoided, thereby improving the efficiency of machining.

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At present, although the share of nickel-based alloys only accounts for 3% to 4% of the alloys processed by Mécaprec, "but this success allows us to see opportunities in other markets," Mr. Gomez has increased his confidence. This success encouraged him to test another tool from Mitsubishi Materials: the new WSX445 face mill. “Indexable inserts with a clearance angle of 0 degrees achieve sharp cutting and reduced cutting forces through their double-sided Z-shaped structure,” explains Mr. Méteil. Since the indexable insert has eight cutting edges, "the cost of the indexable insert can be reduced by almost half compared to the inserts used so far for the same efficiency." To further drive the company forward, in the near future you can also hear stories about aspects such as the automation of chip recycling, expanding the scope of the company's skills and continuously adapting it to a rapidly growing market.