Celebrating its 30th year of business, Tml Precision Engineering is a tier oneand tier two subcontract manufacturer that invests in the latest technology to service leading OEMs and supply chains in the aerospace, motorsport, medical and renewable energy sectors. To extend its competitive advantage, the Norwich-based company utilises cutting tools from Tamworth-based Industrial Tooling Corporation (ITC).

Working to ISO9001 and AS9100, Tml has invested in multi-pallet five-axis machine tools from Matsuura and DMG Mori, turn-mill centres from Mazak, and turning centres from Mazak and Nakamura-Tome. With high-quality machine tools offering extended periods of unmanned machining, the company was looking to improve its tool life while simultaneously reducing cycle times and, consequentially, its commercial advantage. An initial market review led to ITC based on service capability and technical support.

Local ITC technical engineer Dan Smith called intoTml and initially trialled several ITC 2041 series of solid-carbide end mills for aluminium machining. Applied to a series of battery system components for a Norfolk-based automotive OEM, the initial trial proved fruitful with productivity rates and tool life both improving. The improved results led to the 2041 series and other aluminium specific end mills seeing adoption on the shop floor. This success also gave the manufacturer confidence to trial the Widia range of indexable turning tools. Results were once again impressive.

The Widia Victory series of CNMG and WNMG indexable inserts from ITC for machining steel and stainless steel were applied for rough-turning a family of more than 10 different flow regulator and pipe assembly components. Machined on one of the company’s Mazak Integrex turn-mill centres, the ITC engineer swapped out the previous inserts and retained ‘like-for-like’ cutting data with the four-edged inserts. The ITC Widia Victory turning series yielded a tool life of 16 parts per edge compared with the previous four parts per edge. This significant tool-life saving is proving hugely beneficial for Tml, especially as the pipe assembly parts are high-volume components manufactured throughout the year.

One of the parts in the assembly was particularly challenging, as Smith recalls: “Acomponent manufactured from stainless steel bar has a seam weld that results in intermittent cutting, which is why tool life was an issue. However, the performance of the Widia Victory turning series massively improved tool life, while another benefit was reduced insert changeovers and subsequent cost reductions. To further reduce costs in the turn-mill department, we introduced the latest Widia WCE4 series of solid-carbide end mills. Using 3, 4, 6 and 8mm diameter end mills with variable helix flutes, tool life improved and the variable helix enhanced surface finishes and reduced vibration during machining.”

Following the earlier successes established for aluminium milling and the subsequent introduction of small diameter end mills to the turn-mill machines, ITC had an opportunity to look at other milling projects.

An aluminium component machined regularly by Tml in batches up to 100-off required 30mm of metal removal on the face. Previously, the company was using a four-flute solid-carbide end mill from a rival supplier, which was resulting in poor tool life and surface finishes, primarily due to vibration and poor chip evacuation. Furthermore, with poor surface finishes and excessive noise and vibration, Tml had to use one end mill for rough machining and a second tool for finishing. The ITC engineer rapidly eradicated this requirement with the introduction of a 16mm diameter ITC 4104 series aluminium roughing tool with chipbreaker. To maximise the rigidity of the set-up, Smith introduced a Big Kaiser HMC chuck to complement the end mill.

The combination of the 4104 chip-breaker end mill and the Big Kaiser HMC chuck enabled Tml to take a full flute 30mm depth of cut and run at 10,000rpm with a 1.8mm step over and a feed rate of 7200mm/min. On a batch of 80 parts, the ITC 4104 series proved to be a more cost-effective tool that subsequently reduced the cycle time by upwards of 20% while improving the surface finish substantially – to the point that a secondary finishing tool was not required. The single tool machined the entire batch of 80 parts and saved more time with no additional tool changeover or cost implications.

In combination, the benefits of the respective tools have been significant after just six months of working with ITC. However, the most impressive result to date was the latest part subjected to ITC optimisation.

A large EN8 component for the entertainment industry requires 77% material removal, taking the part from 9kg down to just 2kg. On the rough facing of the component, Tml was previously applying a face mill, which was yielding a roughing cycle time of 1.5 hours. The ITC engineer swapped out the face mill for an ITC 16mm diameter 6054-16 series six-flute end mill with a chipbreaker. With a 50mm flute length, the 6054-16 series cut at a full 50mm flute depth with a 0.8mm step-over and a cutting speed of 4777rpm. Cutting with such aggressive material removal rates on a Matsuura MAM72, the stability of the end mill saw further enhancement with the deployment of a Big Kaiser HMC chuck that offers complete face and taper contact. The combination of the chuck and 6054-16 series end mill cut the roughing cycle from 1.5 hours to just 15 minutes. With a quantity of 60 parts, the cycle time reduction is equal to more than three days of machining.

Most engineers would be happy to deliver such a substantial saving for a customer, but not the engineers at ITC. On the same part, Smith identified an opportunity to remove a 90° indexable end mill for interpolating bores. Replacing the indexable tool with ITC’s solid-carbide 4081 series of four-flute end mills with AlTiN coating, another 45 minutes were shaved from the cycle time, taking the complete cycle time from 3 hours to just over 60 minutes.

Concluding on the working relationship with Tml, Smith says: “We’ve worked with Tml for a little over six months, but the results have been exceptional. This is a credit to the receptiveness of Tml to adopt new techniques that improve their cycle times and reduce tooling costs and consumption.”
For further information www.itc-ltd.co.uk

Despite only opening its doors for business in 2002, Oakley CNC Machining has undergone a major transitional shift in its machine tool technology in recent years to support its relentless growth trajectory. Initially starting with Herbert capstan lathes and a selection of two-axis CNC turning centres, the company has rapidly evolved its investment strategy, with the latest acquisition being a Nakamura-Tome WT150IIF twin-spindle twin-turret turning centre from the Engineering Technology Group (ETG).

Already progressing through a transition period, it was the company acquisition by Ian Oakley in 2015 that led to an acceleration in capital equipment investment. Unfortunately, the performance, capabilities and service support from some machine tool vendors fell short. With an order book continually filling and capacity at a premium for the Burton-upon-Trent subcontractor, the company searched the market for a twin-spindle turning centre – and it was the Nakamura-Tome WT150IIF that caught its attention.

Oakley CNC Machining’smanaging director Ian Oakley says: “We’ve taken full advantage of the 130% super-deduction tax allowance and invested in several high-end CNC turning and milling centres. However, not all acquisitions have performed as we would have liked. As we have several new projects that require production volumes of 10,000+, we needed a high-performance turning centre to absorb the volume.The Nakamura was the perfect choice.”

Oakley CNC Machining searched for a twin-spindle, twin-turret turning centre with an intuitive CNC interface that could offer both conversational and G-code programming.

“We wanted a user-friendly machine capable of machining the range of parts we produce, but we got so much more,” reveals Oakley.“One factor that drew us to the Nakamura is the oscillating servo [oscillation cutting] that prevents long strings of swarf and enables us to extend our unmanned running. This was particularly important as we have a family of nylon parts required in production runs up to 10,000-off. Required for the rail industry, the project involves a family of 40mm diameter parts up to 100mm long that we can set up on the Nakamura and leave to run for days without manual intervention. In fact, it was the swarf-breaking technology and the ability to run long unmanned periods that won this contract for our business.”

Before the arrival of this project, the initial prompt to invest in the robust turning centre was in fact a brass electronic component for the construction and earthmoving equipment sector. The company regularly machines the brass electronic part in batches of up to 15,000.

Discussing this component and why the Nakamura WT150IIF was needed, Oakleysays: “This part was being machined on an existing twin-spindle turning centre, lights out, but we were having issues keeping the component in pristine condition with no marks. The existing machine has a traditional parts catcher with swarf deposited in the parts catcher area from machining. The parts, when ejected, land on top of the swarf, which is far from ideal. In contrast, the Nakamura has a robotic arm that unloads the parts very gently and ‘places’ them into a separate unloading conveyor belt. This capability in itself is a big bonus, but coupled with the benefit of having an extra turret, we’ve reduced cycle times from 3.5 minutes to 1.5 minutes. Considering the batch sizes, we’re now saving just over 500 hours per batch.”

He continues: ‘’We previously machined another aluminium part for the food processing industry on our existing twin-spindle machine that is just over 200mm long. This part needed four different operations due to the sub-spindle bar capacity being very limited, incurring significant set-up time and taking a lot of capacity from our machine shop.The overall cycle time was 6.5 minutes. We’re now able to produce these on the Nakamura with a cycle time of 3.5 minutes in one-hit.’’

As a long-running project that has been ongoing for more than three years, the Staffordshire manufacturer was struggling to keep up with demand prior to the arrival of the WT150IIF. The major saving on this project for the ISO9001-accredited company is not just the cycle time but the reduction in set-ups, the ability to free capacity from other machines and the reduction in manual intervention.

“It was a labour- and machine-intensive process,” states Oakley.“Now, we can set the job on the WT150IIF and it will run unmanned 24 hours a day for up to two weeks with the swarf-breaking technology. All we have to do is feed the bar into the machine and collect the finished parts from the other end. The stability of the machine also means that we don’t even have to change the tools in a two-week long production run.”

As the company gains familiarity with the machine following its arrival at the end of 2022, it is moving more parts to the Nakamura.

“The brass and nylon parts are long series runs and we’re benefitting from the combination of the swarf-breaking technology and the one-hit capabilities of the WT150IIF,” says Oakley.“We are continually moving more jobs to the Nakamura and will likely need another machine in the near future.”

Discussing the service from ETG, Oakley concludes: “We have machine tools here from a range of vendors and the service, and the quality of the machines has been indifferent. It’s only been a matter of months since we installed the Nakamura, but we’re delighted with the machine and the service from ETG has been exceptional. If we have ever had any issues, the service team have jumped on the issues immediately. We are currently planning to double the size of our facility to nearly 700sqm, a move that will help facilitate our growth. When we have our new building, we’ll definitely be looking to purchase more Nakamura machines from ETG.”
For further information www.engtechgroup.com