Five-axis VMC made in UK

Underlining its commitment to the British machine-tool industry, Yamazaki Mazak has launched its latest simultaneous five-axis machining centre – the CV5-500 – which will be the only machine in its class to have been completely conceived, designed and built in the UK. The CV5-500, which is currently being manufactured at Mazak’s Worcester plant, is being marketed at a highly competitive price point, making it suited to subcontractors, start-ups and job shops.

Mazak’s versatile five-axis machine features a high-rigidity bridge construction and a fully supported travelling trunnion table.
“While the numbers of British machine-tool builders have dwindled over time, Mazak has continued to invest in its UK R&D and production facilities,” says Alan Mucklow, managing director UK & Ireland sales and service division at Yamazaki Mazak. “The CV5-500 is the latest in a long line of Mazak machines to have been fully designed and built in Britain.”
Mazak’s CV5-500 features a newly designed constant overhang headstock to maintain machining rigidity, even at the full extent of the Z-axis stroke. The machine is equipped with a 12,000 rpm spindle offering 18.5 kW and 119.4 Nm, making it suitable for a range of materials. An optional 18,000 rpm spindle, which includes core cooling through the X-, Y- and Z-axis ball-screws, is available for high-speed applications.
The CV5-500 is equipped with a high-rigidity Sankyo table, driven with roller gear cam that provides a wide angle of rotation, specifically 220º in the B axis and 360º in the C axis. The CV5-500 delivers agile performance, with rapid traverse rates of 36 m/min in the X, Y and Z axes, and can process workpieces up to 500 mm in diameter by 320 mm tall, and up to 200 kg in weight.
For further information www.mazakeu.co.uk

Spinner machine reduces pump part set-ups

A fundamental change to the way stainless steel pump bodies are machined by subcontractor Metaltech Precision Engineers is resulting in far-reaching benefits. The advantages include a reduction in set-up time that lowers economical batch size by a factor of four, shorter lead-times, faster cycles, savings in the cost of tooling, and less wear on the machine tool.

Additional gains associated with the new production route are reductions in power consumption and in space taken up on the shop floor. Both are in short supply at the firm’s Hailsham factory and were the main drivers of the company’s desire to find an alternative manufacturing process.
High-value 500 mm or 630 mm twin-pallet, 50-taper horizontal machining centres (HMCs) with box ways and high spindle torque, of which there are nine on site, together with CNC lathes, have underpinned pump body production since the company was established in 1976. The components are typically produced in five operations on three machines.
A 40-taper, five-axis vertical-spindle machining centre, a German-built Spinner U-620 without a pallet changer supplied as a turnkey package by sole UK agent Whitehouse Machine Tools, now machines the components in two operations. Installed and operational within one week during November 2019, the cell heralds a progression at Metaltech from the use of raw power to smart machining methodology.
The pump bodies in question, of which there are eight types ranging in diameter from 160 to 280 mm with numerous different port details, are produced for a customer in batches of 50 to 60 to a monthly schedule that might include as many as 15 component variants. Sometimes orders were impossible to fulfil and discussions had to take place regarding alterations to the schedule, largely because the traditional machining process takes 10 to 15 hours to set up. After skimming the back face of a 316 stainless steel casting, the process involves roughing the same face on an HMC, and then roughing the front face, bores and ports on the same machine. The part is transferred to a lathe to turn the port details using single-tip boring bars, before returning to a HMC to re-skim either the front or back face so that a location can be provided for mounting the part on a window fixture upon which the finish-machining of both faces takes place. Producing of a batch of 50 to 60 bodies takes four weeks by this method.

In contrast, set-up on the Spinner takes just one hour and the new process route is completed in two set-ups, which means that 10- to 15-off can be produced economically. In the first operation, roughing and finishing of the back face and the interpolated bores are carried out by 16 mm diameter, solid-carbide end mills from MA Ford.
A Schunk pneumatic zero-point fixturing system presents the part to the spindle for the second operation in a time that rivals the speed of an automatic pallet changer. Then, a probe double-checks the datum and that the bores machined in the first operation are the correct size. Face mills complete the rough and finish machining on the front of the pump body. The savings offered by this method of production sees all 50 to 60 bodies completed in one week, rather than four.
Metaltech’s managing director Doug Murphy says: “We sent drawings to Whitehouse and they came back with set-up and cycle times on the Spinner that looked really good, which was largely down to producing the bores by circular interpolation milling instead of single-point turning on a separate lathe.
“We were worried that it would be difficult to hold the required 20 µm diameter tolerance using this method,” he continues. “However, our fears were allayed by a set of three cutting trials the supplier carried out in its Kenilworth showroom. We checked the bores on our CMM for size, ovality and taper, and they were within microns.”
Technical director Mick Bignell adds: “Another concern we had was that the new method of roughing and finishing the back face completely before turning the part over to machine the front face and outside would put stress into the casting, causing distortion and movement of the datums. This also proved to be unfounded.
“We had to look carefully at the surface finish of the internals and bores, as these rotary lobe pumps are used in the food industry and any roughness could cause hygiene problems. External finish is also important to our customer, as the polished appearance is a sales advantage. The interpolation milling cycles established by Whitehouse have proved to be equal to these requirements, producing a finish equivalent to single-point turning.”

Savings in tooling costs result from the new production method. The first thing to note is that on the HMCs, which use large indexable-insert cutters for roughing, the 60-station tool magazines are not big enough to accommodate all the cutters needed for every pump variant. On the Spinner, with the new process allowing commonality of tooling, the 32 pockets are sufficient to machine the complete range.
Using a waveform rough milling strategy with the 16 mm diameter cutter at high speeds and feeds, typically 2700 rpm and 2400 mm/min, rapid metal removal rates are achieved without unduly heating and stressing the part, helping to maintain accuracy. It is largely this lighter machining that allows the BT40 vertical-spindle machine to attain the same level of precision as a 50-taper HMC when cutting tough stainless steel.
Tool life is very good, according to Bignell. He says that one 16 mm end mill can rough 22 pump bodies, while a finishing end mill had completed 50 parts and was halfway through the next batch at the time of interview. A further benefit of these £120 solid-carbide cutters is that two or three regrinds are possible at a cost of £25 per time. Overall, the lower cost of tooling represents a monetary saving that Bignell describes as “immense”.
A further economy derives from reduced power consumption. The Spinner draws between 10 and 20 A current, whereas an HMC pulls 30 to 40 A. Murphy estimates that overall electricity usage will fall by two-thirds using the new pump body manufacturing process.
He concludes: “As demand for these pumps is continually rising, finding more efficient ways of manufacture is imperative. The reduction in set-up time from as much as 15 hours to one is a big game-changer with the Spinner, as is the elimination of work-in-progress.
“The process has lowered the economical batch size and is helping not only to increase flexibility of production but to reduce cost,” he continues. “Furthermore, by handling the parts fewer times, there is less risk of scrap. The customer also benefits, as they are able to reduce stocks levels.
“The ability of Whitehouse to turnkey this installation successfully has given us a path to expansion that was difficult to see before. We were out of space and out of power here in Hailsham, and the high cost of relocation was not an option. The Spinner U-620 requires half the floor space of an HMC and one-third of the power.
For further information www.wmtcnc.com

Kingsbury represents Gefertec

Already the sole sales and service agent in the UK, Ireland and Gulf region for two metal additive manufacturing (AM) machine producers in France, Kingsbury has been appointed to represent German WAAM (wire arc additive manufacturing) equipment builder Gefertec GmbH in the same markets with immediate effect.

Target industries are aerospace, especially for producing high-quality titanium and nickel alloy parts, tool and mould making, the rail sector, and job shops with their small batch sizes. Compared with traditional subtractive machining, cost savings of up to 70% have been reported when processing difficult-to-machine alloys, and up to 50% when dealing with other metals.
For further information www.kingsburyuk.com

Goodfellow donates materials

Research materials supplier Goodfellow is showing support to several initiatives in the fight against COVID-19, supplying materials that are being used to make protective equipment for frontline workers.

The company’s latest donation has seen it donate 130 kg of polypropylene coil to Stamford School in Lincolnshire, where design technology teachers are voluntarily manufacturing 1000 protective face masks a day. The school is contributing to the national effort to increase the availability of PPE for frontline NHS staff.
For further information www.goodfellow.com

Quiet revolution aided by XYZ machines

Tranquil PC – a specialist in rugged, fan-less computers – was started on the kitchen table of its founder David Thompson, with the company outsourcing and offshoring all of its chassis machining to suppliers in China. However, as the business grew, the logistics of shipping from China, and the associated risks of products being copied, saw the decision taken to bring the majority of machining back to the UK and, more specifically, in-house. The company chose XYZ Machine Tools as its supplier for vertical machining centre capacity.

“Our first move was to purchase an XYZ Mini Mill 560, initially for R&D work,” says director Phillip Thompson. “That machine was soon working to capacity seven days a week, not only on R&D, but also production. To ease the workload, we added two XYZ 710 vertical machining centres to create our first machining cell.”
Thompson admits, at the time, no one at the company was a “seasoned machinist or programmer”, but the machines provided a good introduction thanks to the intuitive nature of the Siemens control systems and the level of support from XYZ Machine Tools.
This support was integral to the next phase of investment, which saw an additional XYZ 710 VMC and another Mini Mill 560 installed to meet demand. With these machines in place and running five days a week, eight hours a day, Tranquil PC wanted to complete its second cell, choosing an XYZ 750 LR (linear rail) machining centre equipped with advanced Renishaw probing technology.
“In-house machining has definitely been a driver of our growth, and now that Tranquil PC is part of the French IT group 2CRSI, we have significant plans for further investment,” says Thompson.
For further information www.xyzmachinetools.com