Nakamura from ETG is 80% More Productive

The disruption of the pandemic for the aerospace supply chain has been catastrophic for some businesses, and for those that remain, the challenge is to now ramp up production to meet the returning demand. Coventry based Harris RCS Precision Engineering is one business that has successfully navigated this period and is now looking to take full advantage of the upturn with the recent installation of a Nakamura-Tome WT100F from the Engineering Technology Group (ETG).

Established in 1974, Harris RCS Precision Engineering is a subcontract manufacturer that specialises in the aviation, defence and electronics industries. Like many businesses impacted by the pandemic, Harris RCS has quickly had to ramp up production with reduced staff resources in recent months. Commenting upon the upturn, Harris RCS Managing Director, Mr Graham Harris says: “Primarily working in the aerospace industry, we were inevitably impacted by the pandemic, and we’ve had to ramp up our production with less staff. This has given us the impetus to invest in new technology and automation to meet the rapid upturn in demand. With several twin-spindle single turret machines and a twin-spindle twin-turret machine on the shop floor, we needed to accelerate productivity further and reduce shop floor operations by completing more jobs in ‘one-hit’ – the Nakamura-Tome WT100F was the perfect solution.”

Andrew Dolan from ETG discusses the Nakamura machine with a Harris RCS team member

Harris RCS already had an ageing Nakamura that was over 20 years old, and its existing twin-spindle twin turret machine requires considerable setting time, which made it better suited for longer production runs. The obvious solution was to replace the old Nakamura with a new machine that was capable of ‘one-hit’ machining of complex parts whilst providing fast changeovers for the machining of batches from 30 to 1500-off. With 23 CNC machine tools on the shop floor from a variety of manufacturers, Harris RCS had no allegiance to a specific brand, but having a Nakamura that had run reliably and consistently for more than 20 years – the company was confident in the quality and reliability of the Nakamura brand.

As the first machine purchase from ETG, the Nakamura WT100F was commissioned at the start of the year. It has rapidly made an impact on the machining of aerospace components such as valves, unions and fixtures for wings, fuel control systems and undercarriage. Machining everything from aluminium, stainless, inconel, nickel alloys and other aerospace-grade materials, the Nakamura has increased productivity by upward of 80%. “We are running efficiently with one operator running two machines in many instances, but with the twin-spindle twin-turret on the WT100F, it is like having one operator running four machines as the Nakamura undertakes simultaneous machining on the main and sub-spindle to slash our cycle times. What is equally important is that we have significantly reduced our secondary operations.”

With two powerful 11/7.5kW spindle motors and capacity for up to 48 tool positions with driven tool flexibility with 7.1/2.2kW of power, the heavy-duty Nakamura WT100F delivers a powerful turning solution with unfathomable stability and rigidity. At Harris RCS, this stability is enabling the company to eliminate grinding operations in many instances. As Graham continues: “We have some components that were previously sent for finish grinding, which removed our 100% process control and extended our lead times. We have one particular job that has a tolerance band of +/-0.008mm, which was previously finish ground. The precision levels and surface finishes on the WT100F enables us to finish turn the parts and completely eliminate second-op grinding. We have also run these parts through SPC to check tolerances, and the repeatability of the Nakamura is excellent.”

Increasing Throughput

The flexibility has reduced secondary operations throughout the facility with more parts coming off the Nakamura complete and ready to ship to customers. Whilst this is making an impact on the shop floor, the overall productivity level of the Nakamura is exceptional, as Graham adds: “The machine is 50 to 80% more productive than our other machines. This is a combination of the robust platform that enables heavy-duty machining as well as the simultaneous sub-spindle machining, which is effectively like having two machines running in one compact footprint.”

On one austenitic stainless steel part that is very difficult to machine, the Nakamura has revolutionised the process. Previously machined in one 2 minute operation with a subsequent 40 second operation, the Nakamura now completes the aerospace part in 1 minute 30 seconds. Furthermore, with an OD and ID bore tolerance tied together at +/-0.012mm – the parts required considerable setting-up time for the secondary operations. This labour-intensive task has been eradicated with the Nakamura.

The shop floor staff at Harris RCS thoroughly enjoyed the new Nakamura machine

Service

Looking at the service provided by ETG, Graham says: “Whilst we already knew the Nakamura brand is proven for its quality and reliability, we were not familiar with the ETG service as it was our first purchase from them. However, the service has been excellent – they really can’t do enough to help. We had one small teething issue with the control system and when the engineer rapidly came out to resolve the problem, he asked if we needed any help with our new acquisition. He then spent the rest of his day working with our team on programming tricks and tips – nothing is too much trouble for them.”

Looking to the future

As the Coventry manufacturer continues to ramp up production rates in line with the aero industry exiting the pandemic, Graham adds: “The pandemic has accelerated our plans to introduce new technology and automation into the business and the Nakamura WT100F is a perfect example of how we are adopting new technologies and methods to increase throughput, enhance the customer service experience and compress our lead-times. The Nakamura is also reducing the burden on our shop floor team, as they have fewer set-ups, and they can comfortably run the WT100F and other machines simultaneously.”

“Whilst the Nakamura has been perfect for our business, we still visited MACH 2022 to see if there was anything else that may turn our heads concerning future investment plans. All the trip to MACH did, was confirm that our decision to buy the WT100F was 100% the right thing to do, as there was nothing at MACH that was any better than what we have. We are delighted with the performance of the Nakamura WT100F and more importantly, the shop floor guys love it too. When we make our next investment, it is sure to be another Nakamura machine from ETG,” concludes Graham.