Why would anyone in their right mind spend money on printing units that will be sitting around idle half the time? Well, for some companies this apparent contradiction will be a price worth paying in order to achieve the Holy Grail of zero makeready times and continuous production.

There's a printing plant in St Petersburg, Florida, where such a nirvana already exists. Cox Target Media invested some $220m (£134m) two-and-a-half years ago in a brand-new facility set up specifically to produce one type of product: weekly mailings of voucher packs to households across the US. The volumes are enormous, involving some 520m envelopes a year. But each run of vouchers is targeted at just 10,000 households in a so-called ‘neighbourhood trade' area, with the voucher content varying accordingly.

The facility is one of, if not the, most highly automated print factories in the world. It runs two eight-unit Goss Sunday 4000 web presses equipped with Automatic Transfer Technology. This means that, while each press is running a batch of four-colour vouchers using four of its units, the four ‘idle' units can be made ready with the plates for the next batch. At the end of each set of vouchers, the units are switched over automatically to the next print run, without stopping, creating a continuous-production environment. There is none of the usual deceleration and acceleration of the web.

At this particular facility, plates also arrive automatically at the presses and are loaded into the autoplate plate changing sytem using robotics. In fact, the level of automation across the entire print, finishing and mailing production flow is such that, once the paper has been loaded into the presses, the consumer is the first person to subsequently touch the printed vouchers. Goss International sales director John Chambers describes it as "the most unbelievable operation you could ever see". At Cox, it seems the printroom of the future envisioned a decade or so ago actually exists.

Various technological advances make the continuous printing set-up possible. The gapless technology in the Goss Sunday web press, with its bearerless cylinders, allows an exceptionally wide opening to be created on the idle printing units during the print run - approximately 10 times bigger than the blanket gap on a typical web press. And the gearless drive means that everything can be synchronised when units come on or off impression during the run.

"There are some big challenges to deal with," says Chambers. "We have a wet web running through the machine at speed, but our gapless technology means there is no chance of it fluttering and catching a blanket, which would result in a web break."

The Cox set-up is a pretty unique application and the ability to totally control all aspects of production hinges on the fact that the firm is producing its own media product, which is a standard format, day in, day out.

However, other applications for the Automatic Transfer technology are more mainstream. For example, it is also in use at a French printer that produces high-quality catalogues involving multiple language variants. The press configuration here is a six-unit machine that prints four-colours as normal, but with two additional black units for the text plates - one printing, one idle - that can be swapped from one language run to the next in just the same way. Other customers using Goss presses for similar editioning applications are in Germany, the US and Canada. There's no installation here in the UK just yet, although Chambers can think of a couple of potential customers "where it would be perfect".

What about sheetfed?
While this type of continuous-production technology is actually pretty established in web offset, where the makereadies are lengthier, can the same benefits apply in sheetfed where makeready times have already been slashed to just a handful of minutes? KBA believes it can indeed have demonstrable payback in the sheetfed space and unveiled its Flying JobChange system over the summer at a special open house at its first customer, AZ Druck und Datentechnik in Kempten, southern Germany.

Here too, it is technical advancements such as DriveTronic directly driving the plate cylinders, and the accompanying Plate-Ident system for precise registration, that makes such a setup possible. Plus, of course, the presence of the requisite number of ‘spare' units. At AZ Druck, the firm is producing single-colour user manuals on a four-colour Rapida 106 perfector. With Flying JobChange implemented, it can perfect a section of manual pages using units one and three of the press, while makeready takes place on units two and four in preparation for the next run. At the end of each specified run length, the press slows to 10,000sph and a cleaning cycle is carried out to clean the blankets, resulting in approximately 20-30 waste sheets. The operator then throws the impression on to the other set of units, the press speeds back up to 15,000sph and production continues.

"It really lends itself to black-over-black at the moment, for example books or pharmaceutical leaflets," explains KBA UK sales director Mark Nixon. "The payback depends upon the application and is very business-specific. But putting two presses into one is a very attractive idea for some companies - you are saving a great deal of labour."

Nixon also points to the crossover point between litho and digital, citing feedback from digital printers who are finding that run lengths above 500 sheets are not cost-effective. As part of the open house in Germany, KBA ran a number of demonstrations to compare the productivity of a Rapida fitted with Flying JobChange to a standard press. One example cited involved eight 16pp sections printed 1:1 mono, with a run of 300 sheets of each. The machine with Flying JobChange completed the task in 41 minutes, while the conventional Rapida took 77 minutes.  

Fast work
KBA's own tests comparing a conventional two-colour perfector with a four-colour equipped with Flying JobChange show that for short-run jobs the Flying JobChange press produces "100% higher net performance", and pinpoints run lengths of up to 1,800 sheets as delivering the most beneficial results. However this creates challenges for other departments too, as scheduling, platemaking and having sufficient paper at the press need to be similarly synchronised and the press operators need to be on-the-ball too, as AZ Druck managing director Günther Hartmann notes: "This is real industrial production... the press crew now knows how a grand prix driver must feel."

Rival sheetfed press suppliers are pretty lukewarm about the concept, even those who could potentially offer the same sort of option on their own presses.

"The technology is there, but people would need to have quite a specific requirement to adopt it, especially when you can stop the press and change the plates in just a few minutes anyway," states Manroland UK managing director Norman Revill. Komori marketing director Philip Dunn observes that some Komori customers have effectively been doing something similar for years, by running with impression off on some units. "The greater trend for printers generally is to look at de-clutching on every unit, just so you can take the unit out. But no printer benefits from under-utilising on a regular basis. If a printer wants to be ultra-flexible they would go for a four-colour perfector."

"To save five minutes during the job change, and that's really all it is, there are much cheaper solutions available than an investment in twice the number of printing units," adds Heidelberg B1 product manager Gernot Keller. "KBA is creating some interest, but is it relevant for today's printers in the UK, where the majority are printing four plus seal over four plus seal jobs? Who would buy a 20-colour press?"

Open to suggestions
Nixon is open-minded and even goes so far as to say that he doesn't rule out the possibility of a 20-unit press at some point in the future. After all, a 12-colour long-perfector would have seemed unfeasible not that long ago. But for the present, his focus is on a more manageable number of units.

"In the main, we aren't talking to people about increasing capacity, we are talking to them about more efficient capacity that makes them more cost-effective," explains Nixon. "Say, for example, you have a four-colour press. It can print straight four, two-back-two, or a combination such as two-back-one as well as black-over-black with Flying JobChange. So you effectively have two machines in one.

"For two possible customers in the UK where we've analysed the investment for specific applications, the customer would have a payback of under four years."

While the Flying JobChange option is unlikely to appeal to typical commercial printers, where the variety of jobs being handled means switching between different types of job and paper stock on an hour-by-hour basis, for printers with a known work mix - for example a long contract involving one- or two-colour work, or editions such as language changes - it has to be worth investigating.