Five-axis fanatic

6 mins read

An aerospace spares stockist has moved into parts manufacturing, snapping up three 5-axis Haas machining centres within a year. Andrew Allcock charts an unusual success story

Letchworth-based SA Group Manufacturing Division (01462 686 300) installed three Haas (01603 760539) 5-axis machines in one year, starting October 2009, with this elevating its technology from its 15-year-old Bridgeport 3-axis machining centres. Image: SA Group managing director Duncan Hammond – buying 5-axis machines on a regular basis Supporting its machining centres, the company acquired a Haas CNC toolroom mill shortly before the Haas machining centres, representing an advance on existing Bridgeport Interact-type knee mill and conventional machine technology. The division is also now travelling the SC21, aerospace supply chain business improvement path, anticipating achieving bronze level this year. It's a rapid trajectory for a company that had no manufacturing capability up until two years ago. SA Group (Specialist Aviation and Specialist Aviation Manufacturing) was established by ex-BAE Systems, Hatfield, employee Duncan Hammond (pictured, above) in 1995 to source and stock aviation spares, both new and second-hand, shipping them worldwide, and specialising in regional jets. Starting with nuts and bolts, it moved into 'rotable' spares and 'rotable' spares management (rotable is an aircraft component that needs replacement after a particular amount of wear or use), and has latterly, in the past two years, additionally bought aircraft and broken them for spares – aircraft such as the BAE 146 (made in Hatfield) and, most recently, a Boeing 737, for example. This spares supply industry is "massive", explains Mr Hammond, who describes his company as an SME operation in this market – the group's 22 employees produce a multimillion turnover – although he adds that the purchasing of whole planes to break makes it unusual within that definition, while the fact that it has its own manufacturing arm makes it doubly so. Typically only airlines themselves would boast such a combination, he suggests. MANUFACTURING PROMPT The company's manufacturing division was established in 2008, through the acquisition of general subcontractor Bowman & Sanderson, and established itself in the late 1940s in nearby Baldock. This was prompted by one of its spares buying customers, which was having difficulty procuring components from its suppliers and which asked SA Group to project-manage part manufacturing. As of September 2010, the manufacturing division has been based in a modern unit close to the spares stocking operation, with Mr Hammond saying that the stockist operation has "brought its quality ethos and approvals to the business over the past two years". And the parameters that shape its stockist business are instructive. Image: The clean, airy and bright machine shop housed close to SA Group's original stockholding operation. High efficiency lighting lights the area The group has ISO 9000 and AS9120 accreditation (AS9120 description here http://chilp.it/ba50f3), which officially allows the company to supply '145 repair stations' (CAA term for a company able to fix aircraft or aircraft components), but customer quality accreditations additionally abound. SA Group does not repair anything, but subcontracts this work to authorised repairers that are themselves controlled. It's a tight ship, in terms of monitoring, traceability and skill sets, while deliveries need to be fast – "everything is wanted within a reasonable time frame, and reasonable in this context means a day. In the stocking business, everything is picked, packed and shipped the same day". Indeed, its stock level of between £3-4 million, approaching the size of its annual turnover, serves to underline the off-the-shelf demand of the industry. CENTRE OF EXCELLENCE The manufacturing division is now promoted as a centre of excellence. It boasts three Haas 5-axis machines (two VF3SSs and one VF4SS), three other VMCs, a Haas Toolroom Mill, two Interact-type knee mills (to support the manufacture of long parts with overhang – seat rails, for example, one of the parts that kick-started manufacturing), plus conventional milling and turning equipment, retained to allow the rapid manufacture of small quantities. "Five-axis is a marvellous tool, if you have a [computer] model to program from, but, in some respects, you can't beat the good old knee-mill and man with 30 years' experience, especially for one or two-offs," advises Mr Hammond. And, to operate this collection, the machine shop claims 12 of the group's employees, more than half the total. The move to 5-axis machine was, Mr Hammond accepts, a large one, so what prompted this leap? "In looking to expand the business, we looked around the market place at auction sites for machinery. What frightened me was the fact much of what I was seeing reminded me of the type of equipment we had at Bowman & Sanderson when I first purchased it. That indicated to me that companies with that type of machinery aren't necessarily going to survive; they are more vulnerable. "What you didn't see were 5-axis machines – there, but not in the same intensity as standard machines or in the companies that were going broke. So we basically bought our first 5-axis machine 'on the fly', if you like, to be able to go out into the marketplace and say 'we can now undertake 5-axis machining'. As a small engineering firm, it is a nice thing to have, a very marketable tool." As to the choice of Haas technology, budget was certainly one consideration, but, as Mr Hammond explains: "It's horses for courses. We are mainly milling aluminium here, not hard steels, while we also aren't putting the machines into a semi-automated environment. The Haas technology ticked all the boxes for us, while existing customer visits arranged by Haas delivered very positive feedback. We went to a manufacturer of alloy wheels, machining from solid aluminium as we do, and they couldn't say enough good things about the company and machines. Image: The first 5-axis Haas was bought 'on the fly', with SA Group opting for highest technology to distinguish itself from the pack, especially those that seemed to be failing with lower technology "That company visit also pointed us towards Delcam (0121 766 5544) as a programming system, since we didn't have a CAM system either, although were looking at three or four systems, some of which that company had already tried and moved on from." SA Group had previously employed an experienced CNC programmer from a nearby company that closed down, who now drives the 5-axis set-up, but no employees had previous 5-axis experience. Haas and Delcam training has supported the transition. CONTROLLING IT Match-IT manufacturing management software (0845 1300 510) was a further investment, to deliver control of the manufacturing operation as a whole, offering scheduling to support accurate capacity planning and on-time delivery. The first 5-axis job, described as "quite challenging", was, in fact, Formula One work, achieved via personal contacts through personnel at the other business. A simple, albeit 5-axis job, the customer was keen to help SA get the job up and running, because it simply couldn't find companies with 5-axis capacity, Mr Hammond explains. The next two machines followed as capacity was filled up, with a bit of excess capacity a definite need in maintaining delivery times for existing customers, while additionally adding new customers' work alongside. On-time delivery is not a luxury for the company, it's a necessity; both to keep customers and to achieve SC21 bronze standard and beyond. The second Haas machine was ordered and delivered once the manufacturing operation moved into the new premises, with the third following a couple of months after that. The availability of machines from stock is noted as a major bonus when wanting to quickly increase capacity. "It's amazing that you can buy this level of technology from stock – but you don't want to be waiting 12-16 weeks, if you want to increase capacity quickly, so this does help," the managing director observes. All three 5-axis machines have trunnion systems fitted to deliver the addition two rotary axes of a 5-axis machine, which can be removed to return the machines to 3-axis format, if required ­– for example, the processing of longer extrusions, up to 1.2 m. In fact, the VF4SS spends half the month working as a 5-axis machine, the other half without the trunnion, with the other two running seven days a week – single shift plus overtime – in 5-axis mode. HAAS TECHNOLOGY The Haas CNC system is a proprietary system, so how was this viewed, particularly by people with experience of the major CNC makes? "For 5-axis work, most of the programming is done off machine, so it is really almost just an interface to set the machine up. Having said that, the CNC programmer was quite opposed to the control, based on previous experience with an older model, but was quickly won over by the latest system," SA Group's managing director explains. "In another case, the man that runs the Haas Toolroom Mill, and who had Heidenhain CNC experience, is also now very happy with the control. He has taught himself, in fact. We don't really have any issues with the control." And, on general service, there is nothing but praise, with any issues that arise being solved without quibble, including the fitting of a new control on one of the machines to complete commissioning and get it running. As to general perception of Haas 5-axis technology, Mr Hammond acknowledges that there is a certain snobbery in this area. "As part of our SC21 initiative, I visited a company that was clearly successful and which ran its business, all aerospace work, on Haas machines, but which seemed almost apologetic about its choice, basically justifying why it had Haas machines. I couldn't get it. I think they're great, for what we do. "I thought, 'if you are running your business as successfully as you are using Haas machines, then there's no reason that I can't'. It's how you perform for your customers – you can have a £250,000 machine or an £80,000 machine, but it's whether you deliver on time and to the demanded quality. We are machining aluminium, and that's no problem. The Haas machines are good, accurate, they keep going and we run them lights out, if required." The profile of work, as at Machinery's early November visit was 20% aerospace, with the SA Group as customer; 60-70% is non-aerospace subcontract, with the remainder aerospace to external customers. An increasing aerospace percentage is targeted, with its current assembled product suppliers a likely target. This holds out the prospect that SA Group's manufacturing arm will machine parts and then supply these to companies that produce an assembled finished product that SA Group will subsequently purchase and stock. Clearly ambitious, the company seems hardly likely to stop at just the three 5-axis machines; but three in a year is enough, just for the moment. First published in Machinery, January 2011