Lee Warren Architectural Metal & Glass has standardised on machine tools from a Swiss manufacturer for 2-D profiling and bending applications at its 64,000sq ft factory complex in Hayes, Middlesex.

Over £1.5 million was invested in new machinery between 2011 and 2014, two-thirds of which was used to purchase a CO2 laser cutting machine, a water-jet profiler and two press brakes.

The company already had experience of using equipment from Coventry-based Bystronic UK Ltd (www.bystronic.com); in 2009, it bought an ex-demonstration 5kW BySpeed CO2 laser profiling machine capable of processing 3 x 1.5m sheet.

It was much faster than the guillotine and punch press combination that the company had been using and produced extra components from each sheet of material, leading to more economical production.

Alex Pollock, production director at Lee Warren, says: “It was our first laser cutting machine, so we evaluated all of the major manufacturers. As we were in the market for a second-hand machine, we were keen to find a supplier that would provide a comprehensive service. We came to the conclusion that Bystronic UK offered the best package, and we have never regretted that decision.”

By 2012, Lee Warren needed a new press brake and reviewed three potential contenders before selecting the Bystronic Xpert 150, with a 3,000mm bending length and 1,500kN capacity.

It was the only one that could produce a test component with a bend sequence that did not cause interference, thanks to the advanced cycle simulation capability of the proprietary BySoft software.

With major contracts in full swing in 2012, including at London Kings Cross Station, Heathrow Terminal 3 and the Olympic Stadium, it was apparent that the 5kW laser was not powerful enough to cope with some materials.

It was therefore exchanged for a new 6kW BySprint Pro 3015, which is quicker, more efficient and can cut 20mm mild steel — one-third thicker than the previous maximum. It can also process 15mm aluminium and stainless steel; the machine operates 24hr a day, six days a week.

Two years later, Lee Warren was tendering for contracts that involved sheet metal components approaching 4m in length (rather than the more usual 3m).

The company was also bidding for contracts to refit various airports (plus offices in central London), where 4m material in 2 and 3mm-thick aluminium and stainless steel was involved. To accommodate these larger sheet sizes, Lee Warren installed a Bystronic Xpert 200 with a 4,000mm bending length and 2,000kN capacity. The controls on both Xpert press brakes are linked to the latest CO2 laser machine’s CNC system.

All use the same BySoft 7 software, so a component that needs profiling and bending can have a single program and pass seamlessly from the BySpeed Pro to one of the Xperts.

2014 also saw the addition of a Bystronic water-jet profiling machine at Hayes — one of the latest ByJet Flex models with a 6 x 3m cutting area and twin cutting heads. Moreover, the 2-D cutting heads can be replaced with a 3-D head to allow chamfer cutting. The Flex replaced an ageing smaller-capacity machine from another supplier.

Mr Pollock concludes: “We chose a bigger bed for the new water-jet machine, so we could cut larger shapes in one piece — such as an entire steel staircase.


“Avoiding having to butt-weld the stringers saves a lot of time and is more accurate. Water-jet capacity is vital for our business, as it allows virtually any material — from stainless steel and aluminium to plastics and rubber — to be. It also cuts glass and is assisting the new division we started last year, Lee Warren Architectural Glass, prior to which we were buying in glass cut to size.”

Maximising sheet utilisation

Another company benefitting from Bystronic technology is AL-Cut AG, which is a nine-man sheet metal-working sub-contractor based near Lucerne, Switzerland. It is achieving material savings of up to 50% as a result of using Bystronic’s new cloud-based ByOptimizer nesting service. Toni Räber, joint managing director of AL-Cut AG, is one of the first Bystronic laser profiler users to adopt this new nesting service, which is designed to maximise sheet metal usage and reduce the amount of waste material left in the skeleton.

Bystronic has dedicated a large amount of computing power at its data centre in Niederönz to number-crunching customers’ data and calculating the optimal nest for producing a given number and shape of components from any size of sheet.

Cutting plans are normally produced at a manufacturer’s premises either manually, using Bystronic’s own BySoft 7 software or a third party’s nesting system. However, ByOptimizer can achieve much better material utilisation by placing parts more closely together, and it is very quick. Moreover, it allows effective use of common-line cutting, where a single laser path (cut in one pass) separates two components.

While machines have been capable of doing this for years, problems can occur due to heat distorting the components, leading to loss of accuracy. ByOptimizer changes all that, as AL-Cut’s experience shows. One day, Mr Räber received an e-mail asking for 800 parts of complex shape to be cut from 10mm-thick mild steel and delivered the next day.

AL-Cut’s laser cutting expert, Thomas Seeholzer, entered the data into the company’s BySoft software, and the file was forwarded to the ByOptimizer on-line service, which is integrated into BySoft to simplify data processing.


At the server, an algorithm was applied to the data to generate a cutting plan. A database incorporating more than 300 parameters provides comprehensive information about cutting processes and the behaviour of different material. Based on this data, ByOptimizer created the ideal cutting plan for the 800 parts.

All relevant aspects were taken into account, including safe cutting paths and feed rates to minimise heat generation around the sheet, the minimum number of piercings necessary per contour, and whether micro-joints should be included in the cutting plan so that cut parts initially remain attached to the skeleton.

After 50min, Mr Seeholzer received the finished cutting plan, on which parts were placed so close to each other that common line cutting was frequently exploited and any gaps were few and small. A considerable amount of space was saved compared with if the job had been nested locally at AL-Cut. The 800 parts were laser-cut from eleven sheets instead of 15 — a material saving of about 30% on this job. Additionally, placing parts so near to each other shortens the cutting path.

Mr Räber concluded: “ByOptimizer speeds the entire work-flow, from the quote, which is easier and quicker to calculate accurately, through to optimal grouping of the parts to be cut on the metal sheet and error-free profiling on the laser. In some cases, we have achieved material savings of as much as 50%.”