Mills CNC, the exclusive distributor of DN Solutions’ and Zayer machine tools in the UK and Ireland, has recently supplied precision subcontract specialist, NTG Precision Engineers (part of the NTG Group), with a new, large-capacity DN Solutions’ multi-tasking, box guideway turning centre.

The machine, a 24” chuck Puma 700LM II, arrived at the company’s new, purpose-built 45,000sq ft manufacturing facility in Gateshead in January 2023. Although still early days it is intended that, when fully operational with the arrival of a steady rest that is currently on order, the new Puma lathe will machine a range of large, high-precision components and specialised tooling equipment for a growing range of OEM and tier-one customers operating in the defence, oil and gas, subsea, electric vehicle, food production and power-generation sectors, to name but a few.

Whether billet or bar work, the Puma lathe will machine everything from prototypes and one-offs, through to small batch series (typically 10-20 off), from a range of materials that extend from aluminium alloys through to duplex and super-duplex stainless steels.

The new lathe, with its integrated mill and drill capabilities, underscores NTG’s growth ambitions and its commitment to continuous improvement.In recent years, this commitment has seen the company not only relocate its entire operations to a new facility on the Team Valley Trading Estate, but also continue to make regular, strategic investments in staff development, upgrading its plant and equipment, and streamlining its processes and systems.

NTG, through a combination of organic growth and through securing/winning new business contracts from new customers, has experienced significant growth over the past 12 years.
A management buyout (MBO) concluded in January 2021, which saw Ignite Growth (a private equity investment firm) acquire a majority stake in NTG has delivered extra impetus and provided the company with a clear roadmap of its future business goals.

Says Mike Hutchinson, NTG’s group managing director:“Our future growth and success will be achieved by continuing to provide a unique and highly-differentiated offering to customers. The main focus, our ‘raison d’être’ if you like, is on delivering high-quality, high-value and competitively-priced machined components supplied on-time, every time.Everything we do is predicated on our ability to strengthen our position as a preferred supplier and a ‘manufacturer of choice’ to new and existing customers operating across the many industries where we operate.”

To help increase its productivity, consolidate its position within supply chains and maintain its competitive edge, NTG has an impressive range of more than 35 high-performance machine tools at its disposal, many of which are characterised by their multi-axis and multi-tasking capabilities.

Explains Hutchinson: “Our five-axis machining centres and multi-tasking turning centresenable us to machine high-precision, complex components and specialised tooling equipment in one-hit.Multi-tasking machine tools improve our productivity and process efficiencies. They help improve throughput and reduce production bottlenecks and pinch points.We are always looking to improve and increase our machining capacity and capabilities in order to meet growing demand.”

It is against this backdrop of continuous improvement that NTG’s investment in the new DN Solutions’ Puma 700LM lathe must be viewed.NTG is no stranger to DN Solutions (Doosan) or Mills CNC, having previously invested in a 12” chuck Puma 3100XL lathe with a 2150mm turning length back in 2013.

“Although not as large as our new Puma 700LM, the Puma 3100XL is still a big machine and, with its rigid design and construction, has many similar features to our latest acquisition and has performed consistently well over the years,” says Hutchinson

This positive experience of Puma lathe technology combined with Mills CNC’s aftersales service and support both proved instrumental in helping NTG make its latest, large lathe investment decision.

Says Hutchinson:“The decision to invest in the new Puma was made for a number of reasons.We knew we needed a large-capacity machine to take pressure of our existing turning resource and to help spearhead our new business growth ambitions.”

As such, NTG prepared a detailed technical and application-based specification for the new lathe and approached a number of machine tool manufacturers with its proposed investment plan: one of the companies approached was Mills CNC.

“Although we have a large installed machine tool resource, we are not beholden to any manufacturer,” he states.“Instead, we select new machine tools based on their performance, capabilities, price and availability. The in-depth research undertaken into the market established that large-capacity Puma lathes, from many manufacturers’ perspectives, have a good reputation and that their accuracy, power, flexibility and reliability are considered ‘second to none.’

“From talking to Mills, we were informed that they had a new Puma 700LM on order and, as such, that it that could be delivered and installed relatively quickly, virtually coinciding with our relocation to our new facility,” continues Hutchinson. “We ordered the machine in September 2022, and it was delivered, installed and fully commissioned in January 2023.”

The Puma 700LM is a large-capacity, long-bed heavy-duty 24-inch chuck lathe equipped with 15kW/1500rpm high-torque (8076Nm) spindle, a 12-position BMT 85P turret with driven tooling capabilities (11kW/3000rpm) and a programmable tailstock. Notably, the machine supplied to NTG featured the latest Fanuc 0iTP control with an on-board 15-inch touchscreen iHMI.

The Puma 700LM has a 900mm maximum turning diameter and 3200mm maximum turning length to help accommodate large, long workpieces. Despite its size, the Puma 700LM is fast with X- and Z-axis rapids up to 12m/min and 10m/min, respectively.

In addition to the basic machine, the investment package included an automatic tool setter, swarf conveyor and high-pressure (70bar) coolant system to increase the machine’s productivity and process reliability.

Although only installed a few weeks ago, the new Puma 700LM lathe is already having a positive impact on NTG’s performance and productivity.Some jobs, previously undertaken on the company’s existing turning centres, are now being machined on the new Puma 700LM – helping to ‘free-up’ capacity. And the imminent arrival of the steady rest will help NTG realise the Puma’s true, large part processing potential.

Concludes Hutchinson:“We are actively promoting, via our new business development team, the capabilities of the new Puma lathe to new and existing customers. We believe that our latest machine tool acquisition will open up new opportunities and drive future business growth.”
For further information www.millscnc.co.uk

Just a short distance from Silverstone, the JRM Group specialises in the design and bespoke manufacturing of solutions for the automotive, motorsport, aerospace, marine and medical industries. The Daventry-based company is also home to a prestigious racing division that has progressed through rallying, FIA GT1 and the GT3 endurance competition. When the ISO9001-accredited manufacturer invested in its first five-axis machine tool, it realised a high-end CAM system was a necessity.

The current plant list at the JRM Group includes a range of CNC and manual turning and milling centres.Recent investments include a DMG Mori LaserTec 30 SLM additive machine and a CLX450 turning centre, but it was the arrival of its first of three DMU 75 monoBLOCKfive-axis machining centres in 2017 that demanded an equally prestigious CAM solution. This is where Open Mind Technologies entered the fray with its HyperMILL CAM suite.

Discussing the introduction of five-axis machine tools and HyperMILL, CNC machinist and programmer at JRM Group, Mike Sutton, says: “We needed to progress our capabilities into five-axis machining and simultaneously realised that our existing CAM package was limited to three-axis machining. Undertaking due diligence with a complete review of the marketplace, we opted for HyperMILL, a decision influenced by the realisation that a lot of our motorsport customers and Formula One teams use this CAM software. It was a fantastic move as our experience of HyperMILL has been fantastic.”

The 40-employee company manufactures everything from prototypes and small batches for the motorsport, aerospace and defence industries, to jigs, fixtures and 3D-printed components, processing a complete array of materials. The closest that the JRM Group gets to production machining is a five-part wishbone assembly for a high-performance sports car customer in Germany that requires several hundred assemblies a year.

Looking at wishbone components produced on a five-axis DMG Mori machine, Sutton continues: “We’re currently using a cycle in HyperMILLcalled arbitrary stock removal, machining 25Cr 04 steel with a 40mm high-feed face mill. The tool is running at 8m/min feed rate with 0.5mm cuts. The cutting tool manufacturer recommended the 0.5mm cut, as the way to machine with high-feed cutters is to take small depths of cut at high speed. This is different to trochoidal milling, where you take larger depths of cut with a smaller radial value.”

When programmed with an alternative CAM system, the wishbone components had a cycle time of 4 hours. By adopting strategies such as arbitrary stock removal in HyperMILL, JRM has improved the machining strategy and cut the cycle time to 3 hours and 5 minutes. The 25% saving per part is impressive, especially when considering the company produces hundreds of wishbone parts a year.

This is just one example of how machining cycles within HyperMILLare making a positive impact on productivity at the JRM Group,as Sutton continues: “We have two seats of HyperMILLand the flexibility to program parts from home, the office or on the machine. Before joining the JRM Group, I hadn’t used CAM for almost 20 years. Today I’m using HyperCAD-S for designing all the jigs and fixtures we produce, and then all the strategies in HyperMILLto reduce my programming and cycle times. I can create models, jigs and fixtures by generating the geometry, surfaces and lines in HyperCAD-S. It may be a challenging thought process to design and clamp some of the parts that we have to machine, but with HyperCAD-S at least we know the drawing and creation of the jigs and fixtures is a straightforward process.”

At the JRM Group, producing jigs and fixtures is a significant role. For example, the company has recently won an order to 3D-print a family of up to 30 motorsport components, which will need finish-machining. To undertake this task, JRM will 3D-print the parts, but the company also requires the use ofHyperCAD-S to design the fixtures for clamping the non-uniform parts for finish-machining – a process undertaken with HyperMILL.

“HyperMILLwas new to me when I joined the company, but now I’m using strategies such as Z-level finishing, optimised roughing, drilling cycles, contour milling, ISO machining and 3D free-path milling with complete confidence. The more I use HyperMILL, the more my programming skills are developing.”

With impressive levels of support from Open Mind and an ever-improving level of experience, JRM is maximising the machining strategies within HyperMILLto reduce cycle times, programming times and machine set-up timessignificantly, while also reducing secondary finishing operations, and improving tool life and spindle longevity.

One example is the 3D advanced milling/complete finishing cycle, as Sutton explains: “We frequently machine large aluminium clutch covers that require a high-quality surface finish. The clutch covers incorporate a lot of flat and round surfaces in different directions and, to get the optimal surface finish, the tool path needs to move in the right direction with an optimised step-over. By applying HyperMILL’s complete finishing cycle, we don’t have to pick individual surfaces or create tool paths that need optimising, we can just select the optimal step-over rate –HyperMILL does the rest. On the clutch covers, we select a small step-over rate of 0.1mm and the machining strategy will automatically determine the tool-path directions for the best surface finishes. This may take longer to machine, but we allocate such cycles to lights-out machining, returning to finished components that require no secondary hand finishing, the following day.”

3D optimised roughing is another strategy within HyperMILLthat further enhances machining performance.

“When we use the 3D optimised roughing cycle in high-performance mode, we can plunge the tool to a large depth and then remove the material radially,” says Sutton.“This strategy reduces the stress and forces placed upon the tool and spindle. By plunging to the full depth, we can use the full tool flute length. Furthermore, by setting a metric step-over value, HyperMILLwill automatically calculate the step-overpercentage based on the tool diameter and the volume of material that requires removal. This enables us to achieve maximum material removal rates while prolonging tool life.”

Concluding on the company’s experience of HyperMILL, Sutton says: “It’s difficult to quantify the savings that we are achieving with HyperMILL, as our production is predominantly low-volume work. However, it’s evident that our business is enjoying success and continuous growth and, throughout this period, our tool life is improving, as is our spindle utilisation and throughput. Additionally, our programming times are continually falling as our experience with HyperMILLgrows and the ongoing development of the CAM system yields greater efficiencies. Essentially, we’re continually increasing our productivity,while our programming and machining times [and our tooling costs] are not escalating in line with output.This is credit to an extremely efficient CAM system.”
For further information www.openmind-tech.com