Speeding up machining

3 mins read

Rapid prototyping business Arrk Europe has opened a 10-machine operation to support a new, rapid-turnaround approach to machining one-offs and small batch runs. Will Dalrymple reports

There’s a price war going on in prototyping, don’t you know. Chinese CNC machine shops are targeting UK manufacturers, rendering domestic 3D printing services faster, but uncompetitive on price, even including the cost of air freight.

This is why Arrk Europe (01452 727700) has set up a new CNC machining facility alongside its 20-year-old rapid prototyping (3D printing) operation, explains Craig Vickers, European operations director: “We don’t want to be involved in that [price war]. We wanted to be able to offer CNC machining capability in the UK that does something more than churning out bits of plastic and metal, and bring in a rapid prototyping mentality. We are starting to see the benefits, in terms of the speed of reactivity. The strategy for us is to make sure that we are able to service the type of accounts that aren’t able to go to the Far East, such as defence and aerospace.”

‘Rapid’ means having the infrastructure to respond quickly, he adds: “For a general, everyday rapid prototyping business, we deal with a thousand quotes in a month: not just CNC machining, but SLA and SLS [stereolithography and selective laser sintering 3D printing]. We guarantee to quote in eight hours. Ninety percent of jobs are quoted in four. That is relatively unheard of in the CNC machining world.”

The facility employs 12 people, including project management and a CAM department operating on a two-shift pattern running from 7 am to 1:30 am the next day. Personnel work with Delcam PowerMILL and PowerSHAPE software (0121 766 5544). On the shopfloor, there are three 5-axis machines – two 500 by 420 by 380 mm (X, Y and Z) capacity DMU 50 Evo units from DMG Mori (0247 651 6120) and a 410 by 610 by 510 mm (X, Y and Z) capacity Quaser MFC 400 U from ETG(01926 298 128) – plus a DMG 50T 3+2 axis machine and six other 3-axis machines including five Bridgeports. (There are no lathes, as it was judged that subcontractors already dominate turned parts work in Gloucester, according to Vickers). Metals cut include aluminium and steel alloys, and quantities range from one- to two-offs, up to hundreds of parts.

Next door, its rapid prototyping unit houses 20 additive manufacturing machines – plastic-only, at least for the moment – and vacuum casting, paint shop and 3D scanning facilities. Vickers points out that the two centres are complementary, so a typical job might be 3D printed in one building and then machined to much higher tolerances in the other.

Although the site has always had limited machining capabilities for rapid prototyping work, these were initially expanded three years ago, when an on-site aluminium foundry shut. Vickers explains that shutting the foundry was inevitable, given declining custom: “We were probably one week too slow to avoid closure. We would produce cast parts in 3-4 weeks, depending on the component. The customer wanted them just a little bit faster.”

Ten machining centres underpin Arrk’s Quedgeley, Gloucestershire facility

Last year, with the new strategy, the Gloucester Technical Centre’s machining capacity then grew again; and that isn’t the end of it. The building has space for more machines, and Arrk Europe is planning a further investment later in the year, provided business goes according to plan.

The Gloucester site works alongside three other Arrk Europe UK operations: design and engineering services in Basildon; a composite technical centre in Nuneaton; plus tooling and injection moulding services in Petersfield.

Arrk Corporation may also roll out these plans to at least one overseas site next year, according to Vickers. The Japanese-owned business also runs rapid prototyping facilities in Alby-sur-Chéran, France; Barcelona, Spain; Bydgoszcz, Poland; Shanghai, China; and Taipei, Taiwan. Each of these facilities operates machine tools to support those operations. In addition, the company is planning to set up CNC machining in Poland, following the recent start-up at the end of last year of rapid prototyping there.

The Shanghai and Taiwan locations each house more than 40 CNC machines, mostly cutting plastic, for many worldwide markets, even the UK: “We aim to offer a service in the UK, but economics may dictate differently,” Vickers concludes.