The MillTurn series of machines manufactured in Austria by WFL are used around the world to produce complex parts to high tolerances.

These components include compressor rotors, for which the company has developed a highly productive method for automated complete machining. A key component of this solution is the TC63-Digilog probe from Blum-Novotest, which is used to scan workpiece contours in a matter of seconds without the need to unclamp the workpiece from the machine.
The compressor rotor is made of GG60 grey cast iron, measuring around 400 mm long with an outer diameter of roughly 160 mm. By using special forming cutters, the rotor is turned and milled on an M40 MillTurn machine down to gauge-block standard in grinding quality. The machine does this automatically in a 24/7 operation, resulting in significantly shorter machining times.
Until now, grinding was required during the rotor manufacturing process because the necessary accuracy and surface quality could not be achieved by milling.
“Although the new process does not allow us to dispense with grinding in all applications, it is however sufficient that our procedure substantially reduces the amount grinding necessary,” explains WFL product manager Manfred Baumgartner.
During the finishing process, the workpiece is initially prefabricated to an excess of two-tenths of a millimetre. This contour is measured on the machine using the digital and analogue TC63-Digilog touch probe. Engineers can scan the entire circumference of the milled profile without unclamping the workpiece from the machine. In this way, the component’s geometrical accuracy and concentricity is determined “in double-quick time”.
From the resulting contour – which is shown on the CNC display – an algorithm calculates the optimum corrections for every tool engagement.
For further information www.blum-novotest.com

Mills CNC has supplied Cheltenham-based Ferrositi Ltd, a precision subcontract specialist, with a Doosan SMX 2600S turn-mill machine featuring a 13” quick-change chuck.

The machine was installed at Ferrositi’s facility in May 2020: a time when many companies were battening down the hatches due to COVID-19.
Making this investment during the height of the pandemic outbreak is typical of Ferrositi, as the company’s managing director Nick Furno points out: “Ever since the company was created in 2012 we have invested in multi-axis machine tools as a route to improving our productivity, operational efficiencies and competitiveness. We are always on the lookout to increase and strengthen our front-line machining resources.”
Despite the lockdown, such an opportunity arose in April 2020 and resulted in Ferrositi making its first investment in Doosan machine-tool technology and – coincidentally – its first turn-mill machine acquisition.
“Both Doosan and Mills CNC have good reputations in the market and, when I was informed that a turn-mill machine was viable immediately from Mills CNC’s stock at a competitive price, I was interested,” says Furno.
Having seen the SMX 2600S at Mills CNC’s Technology Campus facility in Leamington, the decision to purchase the machine was made.
“Already we can see, and appreciate, that the machine is powerful, fast, flexible and accurate,” says Furno. “We’re particularly impressed with its rigidity, ergonomic design and thermal stability. Using a single set-up, the SMX is capable of performing multi-machining processes. As a consequence, we can reduce production bottlenecks and limit stop-start operations.
“The SMX will help us consolidate and grow our position in existing supply chains and sectors, as well as helping to spearhead our move into new sectors and industries, such as the food processing and medical sectors.”
For further information www.millscnc.co.uk

If a manufacturer plans to carry out rigorous turning of demanding materials, such as titanium and nickel alloys, care has to be taken to select rigid, powerful lathes.

This factor is especially the case if the intended applications require sliding-head turn-milling, as these platforms tend to be less robust than fixed-head lathes. With this in mind, Lanark-based aerospace manufacturer Martin Aerospace, selected a German-built Traub TNL32-9P for its latest investment in sliding-head technology.
Supplied by Kingsbury, the machine started producing aerospace parts from tough alloys 24/5 from the beginning of 2018. It has been so successful at fulfilling an ongoing contract for producing aero engine components from titanium, Inconel and stainless steel that the business had no hesitation in returning to the same source for a fixed-head lathe. Installed in July 2019, the Traub TNX65 produces parts from Inconel and Nimonic for the same customer.
Both lathes have reduced multiple operations to one-hit production, making it much easier to hold the required tolerances, which are generally to within ±0.01 mm, although one pin diameter has to be turned on the sliding-head lathe to ±4 µm. At the same time, process cycles have been shortened, by over 90% in one case on the TNL32-9P and by typically 70% on the TNX65. Such significant savings are partly a result of the ability on both machines to have three tools in cut simultaneously, each having a different feed rate for optimum metal removal.
Neil Lawson, operations director at Martin Aerospace, says: “Both machines are ideal for the efficient production of parts in high volumes from tough materials, and are platforms for continuous process improvements. This has allowed us to secure additional work, as we are able to provide significant savings to our customers.”
For further information www.kingsburyuk.com

Mildenhall subcontractor CTPE uses CNC machining centres, as well as fixed- and sliding-head CNC lathes, to manufacture complex, high-precision components for the scientific, medical, electronics and defence sectors.

The latest addition to the plant list is a Biglia B620 YS fixed-head turn-mill centre with Y axis and sub-spindle (both optional) supplied by Whitehouse Machine Tools
CTPE’s new B620 YS is meeting a five-fold increase in demand for a tight-tolerance aluminium connector that forms part of medical equipment needed in the fight against COVID-19. The company has been making the component for the past 15 years on a Y-axis lathe with a single spindle, which meant that the part had to be re-fixtured by hand on the same machine for a second operation, following which manual deburring was necessary.
Using the Biglia, the component is now produced in larger volumes much faster, as well as more accurately and consistently in a single hit, deburring being included in the machining cycle to allow the shipment of 600 parts every week. This elevated supply rate started at the beginning of April and is likely to continue through to September 2020.
Alex Taylor, CTPE’s operations director, says: “The reason for buying the lathe was a significant uplift in orders from the medical industry in general, not only for the connector part. However, we were also on the lookout for a machine capable of raising turn-milling productivity across the board, including of larger components from billet.
“The Biglia provides a good balance for both types of turning,” he adds. “It produces parts up to 620 mm long and, with its sub-spindle, is ideal for one-hit machining. It has been operating 12 to 15 hours every day since it was installed and runs really well unmanned. Sometimes the machine is left for 10 hours without any manual intervention.”
For further information www.wmtcnc.com

Like most turned parts subcontractors, Sub CNC Precision uses its 14 twin-spindle, multi-axis bar autos, in this case all from Citizen Machinery UK, to turn-mill parts in one hit from a wide variety of metals that extend from mild and stainless steels, through copper and aluminium alloys, to exotics such as Monel, Inconel and titanium. Likewise, the company produces components from many types of plastic including nylon, PEEK and Delrin.

The list of industries served is also long, encompassing aerospace and defence, telecommunications, motorsport, automotive, marine, agricultural and medical, the latter accounting for 20% of turnover in an average year.
So when Rolls-Royce was trying to find a suitable firm to produce a particularly difficult pair of plastic components for the Ventilator Challenge UK, it is unsurprising that its email list included ISO 9001:2008-accredited Sub CNC, whose name had been passed to the government’s consortium by Citizen, which had been identified as a critical supplier.
One of the reasons for Sub CNC winning this plastic turn-milling work, as well as subsequent urgent medical contracts, is the option to use on four of its 12 Citizen sliding-head lathes the manufacturer’s patented LFV chip-breaking software. The machining of plastic materials, as well as many metals, results in stringy swarf wrapping itself around the tool and component, forcing the operator to stop the machine frequently for remedial action, compromising productivity. LFV avoids this situation by oscillating the tool by a few tens of microns to break the swarf into small, manageable pieces, the length of which can actually be programmed.
The two components for Rolls-Royce required the use of sliders capable of turning 32 mm diameter bar. At Sub CNC, the only machine of this capacity equipped with LFV is an L32-VIII, which was deployed for producing the most difficult part with drilled and milled features.
For further information www.citizenmachinery.co.uk