28 May 2018 Finishing

Finding an edge in the cutting game

Guillotines may no longer be at the cutting edge of finishing technology as a growing number of options open up, but they retain the capability to become the factory’s biggest bottleneck.

Every printer needs one and every printer has one: not a digital or even a litho press – printers can survive without one or the other – but every printer needs a guillotine. But its purpose is so basic and with so few moving parts that a guillotine can endure for many years, outliving a number of presses.

And because cutting is not considered a profit centre, few printers understand how to measure the performance of this cutting device. Few want to invest in software, handling equipment or a new machine to increase productivity. So long as the guillotine meets the regulations in terms of health and safety, is serviced regularly and is reliable, it will last for many years. And many do.

Perhaps the only time that the guillotine is noticed is when the operator, following the layout of the top printed sheet begins to cut the stack. And then realises that the top sheet has been knocked off and replaced in the wrong position. It is back to the press for a rapid reprint.

More frequently though the guillotine is making itself known by becoming the bottleneck in the production process. As runs become shorter, as multiple jobs are ganged to a sheet, the pressure on the cutting process becomes greater.

This has led many printers to reconsider how they finish print, driving the popularity of slitter/cutter/creasers for digital printing in the main, and with the acceptance that printers need to offer a greater range of products, to the development of rotary die cutters that are simple to operate and suited to short run operation.

Beyond the rotary die cutter comes the flatbed platen with Kama and the lower end of the Heidelberg EasyMatrix range pitched as replacements to the ever popular Heidelberg Cylinder. And there are the newer technologies that commercial printers are considering: cutting tables using a knife or, with increasing frequency, a laser.

Each can remove work from the guillotine and so relieving the bottleneck that many printers face, and can take on jobs that no guillotine can ever achieve, adding to the range of products the printer can deliver and adding value for customers in the cutting process.

The guillotine bottleneck can be eased by the simple measure of keeping the knife blade in operation for a greater part of the time in any shift. This is achieved by switching from manual input of the cutting sequence to automated set up and by removing the manual task of lifting stacks of paper from one pallet, jogging and after cutting putting the finished piles on the pallet, to a handling system.

At its simplest this can be lifts either side of the guillotine and a tray which shakes and jogs to remove air from the pile in order to leave a perfectly square solid block which is easier to manoeuvre and means more accurate cutting.

It also means that productivity does not drop off towards the end of a shift by taking away the energy sapping effort of lifting and moving as much as eight tonnes of paper an hour. It is no surprise that a guillotine operator will slow down markedly towards the end of a shift, let alone increasing the propensity to make mistakes.

At its most advanced in the Baumann Basa systems for Wohnlenberg and Perfecta branded guillotines or the Polar Pace where robot arms lift a pile of sheets from the pallet, run it through rollers to remove air before loading the jogger for an even better pile. The stack is carried to the back table of the guillotine and positioned for the first cut. The operator can then take over, though in some instances the robot arm can take over and rotate the stack for further trimming work – on a pile of posters, for example.

Unsurprisingly few will ever want a system like this. But future generations of robots coupled with artificial intelligence programming, will make handling and cutting around a guillotine into a fully automated process. A cod demonstration at Drupa 2012 had a robot taking a pallet from the end of a press and loading a guillotine. Nothing like this has been introduced commercially, though robot lifting gear is proving effective at a number of printers across Europe.

“Printers can certainly improve the productivity of a guillotine by adding peripheral equipment, stack lifts, down lifts and so on,” says Jason Seaber, technical sales director of IFS. IFS is the UK distributor for Perfecta and its handling system. This includes the ability to divide the different jobs on a sheet to separate pallets, removing another post cutting step.

Currently state of the art, Seaber explains, is a dual configuration where a first guillotine is able to cut the stack into strips and these strips are then pushed under the cutting blade of a second guillotine positioned at right angles to the first. In a high volume environment where there is little product variation, producing wet glue applied labels for canned foods or thousands of business cards a day say, such an investment can make sense. It is not for the commercial printer, nor for short runs.

Friedheim International which is UK distributor for both Wohnlenberg and Schneider guillotines, will also supply the Basa systems from Baumann for the Wohnlenbergs and a similar range of equipment, including a Roboload to move paper from a stack to the jogger and a sheet transport system to move the stark to the back table of the guillotine.

The Polar equivalent is the Transomat, a series of components around the guillotine. When robotic handling is included the series of lifts, and joggers becomes the Pace system using gripper arms to load and turn the stack behind the cutting blade. These can manage deeper piles with no loss of quality than when manual handling is involved.

Few will want this level of automation even if the impact will be a reduction in the number of staff needed to run the guillotining department. As the appeal of heavy lifting in a factory begins to fade, robotics may become more attractive.

However, stack lifts joggers and down lifts are in widespread us and are all appreciated by operators says Ian Trengrouse of Heidelberg UK. “It’s not a massive investment. You want to keep the guillotine running instead of waiting for 40% of the time.

“We see the trend of more jobs being arranged on a sheet which means generating more cutting work for leaflets, point of sale products and more, especially from SRA2 and B2 presses. Those using B1 machines are putting sheets through folders and to stitching lines.

“These B2 printers do not need the full automation, but by the end of a shift handling 4 tonnes of paper an hour, an operator is not going to be as productive as at the start of his stint. Handling systems simply take the stress away from the operator.”

Compucut for Polar and equivalent systems can store cutting programmes or download these via JDF from a job ticket. A US company, Scissorhands, will deliver a programmed cutting sequence from an imposition file loaded to its cloud based servers, so replicating this feature. In most cases coloured blocks are used to identify the different jobs on a stack with the top of range systems using low resolution images to give the operator no excuses for cutting errors.

Even so as short runs increase the guillotine becomes more of a pressure point and many are inclined to ease this with a second machine. There are alternatives.

The smaller multi finisher, comprising slitter, cutter, creaser and perhaps a folder or perforator, can equally remove stress from the finishing department. These have been conceived as devices to automated the cutting of simple print items, assumed to have been printed digitally. Part of the initial appeal was that guillotining a stack of digitally printed sheets could be fraught with risk because of image shift. Cutting one sheet at a time reduced this problem.

The sheet is loaded, the image area identified by a camera and cross cutting and slitting will deliver stacks of small leaflets, business cards or similar without imposing a short run straightforward job on to the guillotine operator.

For many printers the multi finisher sits alongside the digital press to create a production cell delivering finished products with minimum supervision. At the other end of this scale a company like Bluetree will connect a larger version, in this case a Horizon SmartStacker, to perform the same functions. Or it can connect a Rollem unit as part of business card production cell linked to a Fuji Jetprress 720S.

The most populous of these units are those from Duplo. When launched the DC machines became an immediate success and have been a major revenue generator for Duplo.

Alex North is head of digital marketing at Duplo International. He says: “I used to work for a digital printing company where we recognised there was a bottleneck in finishing around the guillotine.

“We had to cope with a lot of different jobs and sizes coming in but a lot were small quantities and directing them to the guillotine meant it would be tied up every day, and restricted our ability to hit tight deadlines. If the order was placed by 3pm through the website we guaranteed delivery the next morning. We needed to invest in a multi finisher.”

After consideration of alternatives from Uchida and Morgana, his company settled on a Duplo DC645, upgraded to DC646. Now North is directly involved in these and their successors. There is a close integration with HP Indigo's SmartStream server to automate set up of the finishing device. “The investment helped us earn a profit from the smaller jobs,” he says. “Now talking to customers at Duplo, their story is pretty much the same, a large number of low volume simple jobs ordered via web to print that tie up the guillotine had caused a problem.”

The move towards shorter print runs and loss of skills from the industry, particularly in finishing, exaggerates the problem as staff are not as well trained and must work across multiple machines.

Duplo offers machines according to production requirements. All are suited to SRA3 digital printing, offering different speeds, substrates, flexibility and functionality and the option to run longer sheets.

The most sophisticated machine to date is the DC746 designed for more complex applications including perforation and faster throughput. Both this and the DC646 are JDF compliant and will hook to the HP server. All three models have a barcode reader to down load the specification of a job and save makeready time. Manual set up is via graphic interface to enable an unskilled operator to run the machine by following the set up wizard.

The company continues to work on new versions, responding to customer feedback. While North is not revealing details, the ability to create rounded corners is close to the top of customer requests.

Morgana’s AutoCut machines are a strong rival to the Duplo products. In a model established by Morgana, the modular approach of its products means that creaser and slitter are combined with a cross cutter to produce a range of products. It will take a sheet to 1,020mm long, producing a six- or eight-page brochure. “It makes handling a long sheet a lot easier,” says marketing manager Wendy Baker.

Those requiring a higher volume can consider the Horizon SmartSlitter from IFS. While coming to the market behind Duplo, Horizon has used the delay to improve on the core design. Consequently all areas of the machine are accessible and the slitting, creasing and cutting or perforating modules are removed by sliding cassettes from the side of the machine, rather than lifting out.

For IFS technical sales director Seaber, the interest in this technology is increasing as print becomes more and more digital. “People are more open to a different approach.”

Another step up the productivity scale is the Rollem range of cutters. These were initially developed to process playing cards and this have round corner capability. With the growth in popularity of automated inline production, Rollem is positioned to take advantage processing B2 as well as smaller digitally printed sheets.

The top of the shop, however, is the Swiss made Bograma machines, sold in the UK by Friedheim International. These are sold as rotary die cutters, but with head and tail trim knives in place will slit and cut out products at speeds and levels of accuracy that guillotines cannot match. With fold and stitch units in place, this becomes a unit to deliver high volumes of small booklets says post press sales specialist Mitchell Ball.

The Bograma, he argues, is a viable alternative to a second guillotine. As well as the standard slitting and cross cutting, the BSR models are rotary die cutters using magnetic dies to create a value added finish for all manner of promotional material, direct mail and business cards.

It will also crease, emboss and perforate running at 9,000sph 550mm across sheets on the standard machine or 12,000sph on the servo version. The additional tools can be purchased after installation of the base machine.

Rotary die cutting like this is predicted to be the next investment trend for commercial printers. While the Bograma is at the top of the range, Horizon, Morgana and Duplo have less sophisticated and less expensive machines. As well as creating cut outs and producing innovative marketing material, these can be used to kiss cut labels, to add textured effects and to cut out lightweight cartons, so providing an entry to the niche end of the packaging market.

“We are getting a lot more interest in the die cutter,” says Seaber. “Printers realise that they can add a lot more value within a standard type of product, enabling them to be innovative and creative.”

And while the dies are an investment, they can be used for standard products, tent cards for example, with changed content. The rotary die cutter will also an innovative touch to business cards, offering rounded corners or cut out elements, for example.

Just as there are growing number of alternatives to the guillotine, there is an alternative to the Heidelberg Cylinder for cutting and creating purposes. While these work horse machines are as in as much demand as ever, there is growing interest in flatbed platen technology to offer a faster set up, more automated piece of equipment.

The Kama platens were designed for just this purpose, taking the same fast and easy set up principles as the digital presses the machines are designed to match. UK distributor is Friedheim International which is arranging a trip for UK printers to the plant near Dresden to explore the possibilities that are opened up.

Roger Cartwright is in charge of the converting equipment at Friedheim. “This is more than a replacement for the Cylinders or older platens. The Kama is a more effective solution for that level of cutting.”

The machine uses optical registration technology and quick changeover chases. When hot foiling, only the die is heated rather than the bed. It means a faster switch over between cut and crease operation and foiling, says Cartwright, because there is no wait for the machine to cool down.

Most interest is coming from the carton converters and others considering a move into digitally printing of boxes. However, there is a strong case to be made for a commercial printer to make this type of investment. “The major competition comes from laser cutting, but that still does not produce the same quality of cut as a knife,” he says.

Motioncutter has a dozen or so installations in the UK having designed a machine specifically for the printing industry. Trotec in contrast is less prescriptive about who buys its technology. Printers are among the users, however. Bryan Joter points to the five Trotec last cutters installed at stationery supplier Pogo Fandango.

Laser cutting is also suited to producing prototypes for carton design, using the laser to produce score lines as well as the cuts on devices from A3 to 3.2x2.2 metre flatbed formats. The scorch marks that laser cutting had been associated with are no longer necessary. Testing substrates combined with variable power on the laser can result in a clean cut in every aspect.

“Lots of users are cutting white papers and boards without a problem,” he says. “It is very much an added value process. People are looking more and more for what they can do differently, how they might add value to their production.”

An entry level unit will be a £10,000 investment. After that the sky is the limit. Like the multi finishers, Trotec uses a camera system to register to the printed image with a barcode reader to pick up the settings for the job.

Laser cutting was a key trend at the last Drupa with a number of products and concepts on show. Many were linked to digital printing, an SEI systems from Italy running with the HP Indigo; LasX and Polar cutting as a sheet passed beneath a laser followed by a pick and place robot to lift and stack the items cut out.

It is doubtful that a laser will completely replace a guillotine. Printers will still need the sharp blade for many years to come, but it seems there are now many more ways to cut the sheet.

Ruddocks lifts cutting productivity

Ruddocks Design & Print reckons it will achieve a 20% gain in productivity when its 2001 vintage (ageing) Polar 92 is replaced with a new Polar 92N Plus cutting system.

The system aspect refers to the up lift, jogging table and down lift that will be part of the installation and the Compucut software that will speed programming according to production director Ady Potter. 
 
“Our pain point was becoming the guillotine,” he says. “Anything we could do to speed the process up was going to be good.” The Lincoln printer had upgraded its printing and stitching equipment and investment in the guillotine brings that into line with the rest of the business. 

“We are going to save time with the handling equipment because the operator will be concentrating on cutting, not having to knock up the stack first. It is going to make us more efficient.”

The company has a spread of work from short runs to magazines that can reach 10,000 copies of a 64pp publication. Sheets for this need to be trimmed into four pages to view before feeding to the Horizon StitchLiner.

The company also has a Polar 66 to cope with digital work and a Morgana AeroCut preloaded with its standard business card formats which also takes pressure off the standard guillotining work.

“Business at Ruddocks is buoyant. Our design studio is rapidly growing and bringing in print. We have a very loyal print customer base and this is constantly expanding,” says Potter.

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