Cutting, welding, drilling, the laser job shop fulfils what on the surface are the basics of manufacturing. If you want 1,000 shelf brackets cut or parts for automobiles welded, then a laser job shop will deliver the sections as specified. But there is a lot more to running a laser job shop successfully than it would at first appear.
‘The market is very competitive,’ said Dean Cockayne, operations director at Midtherm Laser and chairman of the Association of Laser Users’ (AILU) Job Shop special interest group. ‘You’ve got to have new technology and you’ve got to invest all the time to keep on top of that. You’ve also got to be proactive and chase the orders.’
Midtherm, based in Dudley in the West Midlands, UK, has been in business for 11 years. It runs five laser cutting machines, and, apart from some folding, the company deals almost exclusively with laser cutting. ‘Some of my competitors cut, fold, drill, weld, and maybe even paint,’ said Cockayne. ‘You get businesses that are etching or marking with lasers, some that cut flat parts, and some that cut 3D parts – I split them into several categories and my competition is those that cut flat parts.
‘People are making money out of laser cutting, but they’ve invested a vast amount of money to get that return,’ he added. Midtherm’s laser cutting machines are all in excess of half a million pounds each, and only three of them can fit in one of the company’s buildings. And it’s not just a case of buying the equipment; there’s a lot of expertise that goes into running a job shop. Even manufacturers buying their own laser systems and selling some of the spare laser cutting capacity, can struggle with turning a profit. ‘It doesn’t always work like that. They [manufacturers] might buy an over-the-top machine and find they can only get their own work for it,’ commented Cockayne.
The competition is largely from other job shops providing similar services, according to Dr John Powell, technical director at Laser Expertise, a subcontract laser processing company based in Nottingham, UK. ‘Laser cutting is such a big industry now that you either use laser cutting or you don’t. We don’t compete with anything else really,’ he said. Plasma cutters and flame cutters have a completely different field and water jet cutting is used when laser cutting isn’t suitable. Punching is faster with simple part geometries from thin sections, but lasers are better at cutting complicated profiles.
With this in mind, it is common practice for the customer to send the same job specifications to a number of subcontractors, and copy them all in on the e-mail. ‘They don’t hide the fact,’ commented Powell. ‘So you know who you’re up against and it’s a matter of lowest price, fastest delivery.’
Delivery is usually required within three or four days, according to Powell. And the following month job shops go through exactly the same process, because the other subcontractors might be short of work that month and give a cheaper price.
Laser Expertise, contrary to Midtherm’s strategy, does offer fabrication services. It will not only cut flat box plates, but also bend them into shape, weld them, finish them and paint them. For example, the company makes rubbish bins, sending them out complete, welded and painted, with the corporation logo on. Powell commented: ‘If you are doing that for a customer, they won’t send it out to five different suppliers every week, they’ll keep coming back to you. Fabrication not only adds value to what’s being produced, but it keeps the customers loyal.’
The work at Laser Expertise ranges from more standard cutting jobs to producing highly complex parts. On the day I spoke to Powell, he ran through the day’s work: ‘Earlier this morning we were cutting shelf brackets for shops. You produce a lorry load of the parts in the morning. It’s all mild steel. Later on today we’re going to be cutting some decorative panels for an architect out of stainless steel, which will take two hours each. At the end of the day, two people could pick up the entire afternoon’s production, but because it takes so long to do, it costs a lot more. The jobs can vary quite a lot in terms of throughput.’
Laser Expertise runs three CO2 lasers and has recently invested in a fibre laser. Fibre lasers are more efficient and faster at cutting thin metals, which makes them an attractive proposition for materials processing, but Powell is treating the technology as supplementary to the company’s existing CO2 systems.
‘The CO2 laser is a better general workhorse,’ he said, ‘but if you’ve got two CO2 machines the third machine should be a fibre system.’ Cockayne agrees: ‘Fibre lasers can’t do some of the jobs, but as a second or third option it is well worth having one. They are cheaper to run, more reliable, and they cut faster on thinner material.’
The fibre laser’s speed of processing thinner materials means that, when cutting a lot of metal, all the thin sheets can be given to the fibre laser, for instance. Tom Mongan at Subcon Laser Cutting, based in Nuneaton, UK, also noted that the company has recently purchased a fibre laser system. ‘Fibre lasers have come into their own,’ he said, adding that solid-state lasers, of which fibre lasers are a class, can now cut up to 25mm stainless steel, aluminium and copper, whereas CO2 lasers can’t.
The disadvantages with fibre lasers is that, when cutting thicker sections of stainless steel, more than about 5mm, the cut edge quality is rougher than with CO2, and there can be some adherent dross (droplets of resolidified melt) on the bottom edge of the cut. ‘If you get that on your 6mm or 8mm stainless steel plate, you have to remove it before you can do anything with it,’ explained Powell. ‘This is a problem particularly when trying to stack cut parts on top of one another. You can’t stack them on the pallet because they’ll damage the one below.’
The other issue with fibre lasers is that, because of the wavelength of light they operate at, they won’t cut plastics, unless it’s a special sort of plastic. This can be a problem because a lot of stainless steel is wrapped in plastic, commented Powell. ‘If you are cutting with a fibre laser you have to order steel wrapped in a special plastic that can be cut with a fibre laser,’ he said. ‘That can slow the job down and as the response time of a normal job shop job is about three or four days, then this can cause problems if you have to wait for special plastic to be put on the material.’
Powell added that, in general, fibre lasers are extremely quick and have much lower maintenance costs and lower electricity costs. Mongan at Subcon Laser Cutting noted that although fibre lasers use less electricity than CO2 lasers, they use more assist gas. Subcon has invested in a nitrogen regeneration system, because of the number of lasers the company is operating.
The lasers available today are more powerful and reliable than 15 or 20 years ago. For Powell, it is the reliability of the machines that is the biggest difference between running a laser job shop today and 20 years ago. ‘Now the reliability is much more like a standard production machine,’ he remarked. ‘Before that, there were endless breakdowns.’
The market for subcontract laser processing is buoyant at the moment in the UK, according to Cockayne at Midtherm: ‘We’re working two shifts and the machines are operating 24 hours a day.’
Both Powell and Mongan are also busy. Powell said the job shop market now seems to be genuinely improving: ‘That means jobs are being won on delivery times rather than price.’
However, Cockayne said that even though engineering in the UK is booming, ‘there’s probably not a lot of space within the marketplace now for any more laser job shops’.
With engineering and manufacturing having a bit of a resurgence in the UK, there is plenty of work for laser job shops. But it’s the experience and knowledge of the staff to a certain extent that makes a successful laser job shop – knowledge that is pooled in the UK as part of the AILU Job Shop special interest group – as well as the investment in new laser technology.