All part of the service
Keeping up to date with the latest technology can be a struggle in any industry, and this is certainly the case for laser job shops with the advances being made in fibre lasers for cutting. In a world where equipment is not cheap and system lifetimes are long, it has to be worthwhile to upgrade to new laser technology. In addition, a whole new category of machining service bureau has emerged on the back of the growth in ultrashort pulsed lasers and micromachining, which has just about reached industrial maturity.
Dr John Powell, technical director at Nottingham, UK-based job shop Laser Expertise, noted two big changes in the UK job shop sector over the last few years: the addition of fibre lasers to what was a market dominated by CO2 lasers for cutting, and competition from steel stockholders with laser machining capabilities.
Powell spoke about the UK job shop market at the International Laser Technology Congress, AKL’16, at the end of April in Aachen, Germany.
Steel stockholders, he said, are taking the jobs that weigh a lot, and involve a lot of metal. ‘In the old days there were small jobs and big jobs for laser cutting, and the job shops were doing them all. But, nowadays most of the big jobs are being taken by steel stockholders with laser systems,’ he said. This is because the majority of the cost of the job is in the material, and the steel stockholders get their metal cheaper than job shops.
‘This has changed the UK job shop landscape,’ he continued. ‘Turning a profit as a job shop is more difficult than it used to be. In some cases, steel stockholders are quoting prices for large orders that are the equivalent of what job shops will pay just for the metal.’
Steel stockholders aren’t interested in small jobs; those are still going to the job shops. But taking away the larger commissions is squeezing the job shop sector. One route to compete in the market is for job shops to add value to laser cutting with other services. Laser Expertise offers a full fabrication service, including bending, welding, drilling and painting, alongside the cutting.
The other trend Powell noted was that job shops have started to split their production, adding a fibre laser to existing CO2 laser capacity. Fibre lasers are faster at cutting thin section stainless steel – up to around 4mm thick – compared to CO2 systems, making it cheaper. But with stainless steel thicker than 4mm, CO2 lasers are still the preferred choice most of the time, according to Powell. Subcontractors therefore cut all the thin sheet jobs on the fibre laser and leave the thicker sheets for the CO2 machine. That gives them the best of both worlds.
Fibre lasers cut mild steel with oxygen at a similar quality to CO2 lasers. However, the cut edge on stainless steel and other alloys in sections above 4mm is inferior to CO2 unless specialist techniques are employed. These techniques, however, are generally slower and consume a lot of cutting gas because they need big nozzles, Powell said, meaning fibre lasers are not as efficient when cutting thicker section stainless steel.
‘A lot of job shops now have both CO2 and fibre lasers,’ he said. ‘All the lasers bought recently have been fibre lasers, because the job shops already have CO2 lasers. It’ll be a different situation in six or seven years’ time when the legacy CO2 lasers are dying. Job shops will have to decide whether to buy another CO2 system or purchase fibre laser technology that gives a smooth edge for thicker section stainless steel.’
While fibre laser sales might be up currently, Matt Wood, a senior product manager at laser system supplier Amada Europe, feels that CO2 still has a lot to offer subcontractors using lasers. ‘Subcontractors that need to process a wide range of materials and thicknesses are still not convinced that fibre lasers are good for cutting thicker material,’ he said. ‘These companies have gone down the route of the latest CO2 technology, which I can’t say I’m surprised in a way because in my experience fibre lasers still aren’t comparable to CO2 systems for cutting thicker aluminium and stainless steel. For high quality cutting in thick materials, then the CO2 laser is still the way to go.’
Amada continues to sell CO2 lasers to subcontractors replacing older machines, according to Wood.
‘Everyone seems to want to forget about CO2 lasers, but I think that’s a dangerous game at the moment,’ he continued. ‘Eventually more laser users will get to grips with solid-state lasers and over the next five years or so solid-state laser technology probably will catch up, but CO2 has had a fairly slow-burning progress for 20 years, while fibre systems have come along in four or five years. Everyone seems to be jumping on the band wagon, but for cutting thicker materials with high quality, CO2 is still the better route.’
The speed of fibre laser cutting is only an advantage if downstream processes, like bending or welding, can keep pace. Wood said that there have been a few cases where the job shop has pallets of parts sitting around on the floor with nowhere to put them, so they end up not running the laser, which is self-defeating. ‘You pay extra for a high-power fibre laser and it sits there not doing anything because the other processes further down the line can’t keep up,’ he said.
‘We try and advise people to look at the whole process,’ Wood continued. ‘A laser job shop might think it needs a 6kW fibre laser, but it’s used to a 3kW CO2 laser, so a 2kW fibre laser will be much faster than that. So, the job shop has to think about how it’s going to process the work after it comes off the laser.’
Job shops only get paid when they deliver parts, and they can only deliver parts as quickly as the bottleneck allows. ‘It’s trying to advise subcontractors on what’s best for their overall process, not purely on cutting speed, because that’s not necessarily the end game a lot of the time,’ Wood noted.
‘It’s an interesting time at the moment, because you’ve got the whole crossover between fibre and CO2 lasers, and trying to educate people that you’re going to get an awful lot more work piling through the factory if you invest in a high power fibre laser, so are your other processes in a position to keep up?’
Amada has also seen some customers starting to upgrade their press brakes and welding systems in preparation for a fibre lasers they might buy in the future.
Automation is also becoming more important. Job shops want to run the machine ‘lights-out’, so they can get the extra throughput. There is also the health and safety side of things, especially when handling thicker, heavier sheets – automating the process is safer as well as more productive.
‘Job shops are now looking at every way they can to reduce the cost per part. Buying a fibre laser is one way of doing that in the thinner range of material,’ Wood commented. ‘But another thing that we’ve seen is that more people want to cut as much as possible with compressed air, rather than with nitrogen or oxygen, particularly with fibre lasers.’
Fibre systems primarily use nitrogen for cutting most materials to get the high speeds, but actually the systems can cut with air on a lot of materials up to a similar speed as with nitrogen. That seems to appeal to a lot of subcontractors because it’s less expensive, according to Wood: ‘The subcontractor might have to invest in an air compressor, but then essentially it’s free gas,’ he said.
Cutting mild steel with oxygen gives an oxidised edge, which has to be removed if it is to be painted or welded. Cutting with nitrogen will give a nice clean edge. Air gives a slight golden brown tinge on the edge, but in certain cases this can go straight to the next process. If the edge isn’t going to be seen, or it’s not particularly important what it looks like, then cutting with air will reduce the cost of producing the part.
No job too small
Cutting, welding, brazing, and the like are fairly standard activities for subcontractors with laser processing expertise, but now new job shops are springing up that focus on laser micromachining, a relatively recent form of industrial laser processing based mainly on ultrashort pulse technology. Because laser micromachining is so new – micromachining typically involves using very short laser pulses in the realm of picosecond or femtosecond durations to ablate tiny amounts of material without inputting any heat into the part –equipment suppliers offering ultrafast lasers are also providing access to the technology in the form of micromachining-as-a-service.
4Jet Technologies is one such laser equipment supplier that has opened a micromachining job shop this year. 4Jet Microtech is based in Alsdorf, Germany and focuses on processing glass, thin films and electronic components. The company has historically targeted the automotive and tyre industries, but also has a division working on micromachining, especially ultrashort pulsed laser processes, such as glass cutting and drilling.
‘We believe there is a requirement for micromachined parts from many industries that deal with thin film technologies, fragile coatings, or companies making prototypes for electronics and other areas,’ commented Jörg Jetter, CEO of 4Jet Technologies. ‘Since 4Jet has some fairly new micromachining technology and products, we believe this job shop not only makes sense to generate revenue, but it also helps us sell equipment, because the customers who get to know 4Jet and its capabilities through the job shop might be the ones who later buy their own production machines.’
Typically, customers approach 4Jet Microtech with new processes that require feasibility tests and in some cases process development. The company then quotes the customer a fixed price per part for the service.
Gideon Foster-Turner, head of business development at UK laser micromachining company Optek Systems, which also offers subcontractor services for micromachining, commented: ‘It’s a natural progression from process development and testing to extending those facilities to offering laser micromachining as a service.
‘Now a significant part of our business is based around providing services, either for customers that just want to subcontract out work, as an extension of the development process, or as an interim step before investing in equipment,’ he added.
Optek Systems, with headquarters in Abingdon, UK, has facilities in North America and China and is ISO9000 certified. The company undertakes subcontract work for aerospace, automotive, electronics and semiconductor, along with displays and photovoltaics.
Electronics, which involves various versions of drilling small holes, is a big driver of laser micromachining, according to Foster-Turner. Medical device manufacture is also a growth industry for micromachining.
Optek Systems is able to accommodate a range of volumes, from single parts to runs of millions of components.
‘Running a job shop is different to selling laser processing equipment,’ commented Jetter. ‘A job shop should be cost-efficient with a quick turnaround time.’
He said that in setting up 4Jet Microtech, the company had to eliminate all the organisational and personnel hierarchies that are present in the equipment business in order to be able to react quickly to enquiries – the company’s target is to respond to an enquiry within 24 hours.
‘There is not a typical job shop customer,’ Jetter added. ‘Some want 10 parts for prototyping, while others are asking for 20,000 identical parts to be processed over a period of 12 months.’
4Jet Microtech has a well-equipped application lab which includes many different laser sources, as well as some semi to fully automated machining centres. ‘We bought the hardware in order to develop processes for our equipment customers and, in development work, a lot of this equipment is sitting idle most of the time,’ Jetter commented. ‘The fact that we have this hardware allows us to offer the job shop service at economical prices, because we don’t have to factor in the full depreciation of the initial investment.’
The biggest area for 4Jet at the moment is processing glass, which includes cutting, drilling, and ablation of thin films. Currently this is for customers making microfluidic devices in the biotech field, for glass suppliers to the automotive sector where there’s an increasing amount of interior parts made of glass, as well as for glass for OLEDs – coated glass used in OLEDs has to be cut in a very precise, non-abrasive way to keep the thin films intact, which is why lasers are ideal for this.
Offering a laser micromachining service is a profitable niche market for equipment suppliers, because they have the expertise to develop a process to manufacture the part. ‘There are a huge number of variables relating to the process and the material that would steer you towards an expert service,’ commented Foster-Turner. Then it’s just a case of deciding whether the required volumes mean the production is best outsourced to a subcontractor or an investment made in a laser micromachining system.