The litho printer of today considering investment in the finishing area needs to bear just one thing in mind: think digital.

The prevalence of shorter runs and faster turnarounds is pushing suppliers to develop folders, stitchers, binders with greater degrees of automation to cope with both a shortage of skills associated with finishing, and to allow printers to cope with the type of job that used to be confined to digital printing.

Not all development is headed towards shorter runs. There is also a move towards higher speeds, tying in with increases in press speed, though this is a smaller segment of the market.

In guillotines, both of the major German producers, Polar, sold through the Heidelberg network, and Baumann which owns the Wohlenberg and Perfecta brands, have focused developments on handling and on the workflow systems. The one answers requirements for speed of action where there are large volumes to deal with, the second enables the operator to focus on keeping the cutting blade moving.

There has been development in robotic handling systems where the printed stack is jogged, rolled and a robot arm positions the stack under the blade for the first cut. Where the task requires only four edge trims, as in poster production, the robot can run the entire operation. More realistically, this level of automated handling is directed at label production where eliminating all air and delivering a solid block of lightweight paper to the guillotine is essential. Offloading handling systems can divide the finished labels for example onto separate pallets for further processing or in preparation for shipment.

These systems are by no means cheap. Justification comes with consistent productivity and speed throughout the day with no drop off as an operator tires. There is clearly a labour saving aspect as well.

Automation like this has also been picked up by the vast German online print groups where the need to hook into production workflows is key. In one of the online print shops, there is no time to ask which pallet to process next. A bar code identifies the stack, calls the job to the screen and guides the operator through the sequence of actions.

This is available to all printers and helps eliminate the mistakes that can occur in a busy department processing multiple jobs simultaneously.

Folding is less about eliminating mistakes than it is about automating set up so that a folder can go from job to job quickly. Heidelberg, MBO, and Horizon, as the major providers of this equipment can all set machines from the JDF information stored in the workflow or which is recalled from a previous job. There is no need to tear strips and fold these to set rollers at every fold because the machine will do this automatically from the caliber setting of one piece of material. Likewise, a knife will move into position automatically thanks to servo motors. The gain comes from handling shorter run jobs with minimal make ready, if any, and being able to lift a long run job, slip in the urgently needed job, then return to the longer run a few minutes later.

Because the set up is now part of the machine, there is less need for highly trained operators to set each machine, which increases the staff available for the task, increasing the flexibility of an operation at a time when finishing skills are not being replaced.

Investment will also cut bottlenecks that occur following a press investment. One printer, having installed an XL75, discovered that his folder was taking 45 minutes to make ready, leading to a huge bottleneck in folding. The answer was investment in a Heidelberg Stahlfolder.

The second direction for folder development is in speed. Both MBO and Heidelberg have folders that while restricted in their versatility, offer new levels of speed in production. Pallet feed is essential and the presentation of the stack from the folder of a press needs to be good enough to feed cleanly.

The Stahl TX series achieves 230 m/min folding through making the first buckle plate deliver a one third fold. This enables the sheets to be shingle fed and thus achieve the speed of throughput. It means that printers will need to adjust imposition plans and ingrained habits, but the gain in productivity can be worth it.

MBO’s K8 folder is likewise a folder for a task. It is an all knife machine, so there are no buckle plates to adjust. The pay off is that the folder can only deliver a limited number of formats and again impositions will be different. In a set up where there are multiple folders, the concept of one high speed folder for standard A4 sections and a number able to switch easily from one format to another can be appealing.

The approach of Horizon (supplied here by Currie Group) to folders fits this. It has concentrated on automation, a result of its heritage in smaller format production. This background can hang over the company a little, but is unfair. It has brought ease of use and automation to a market where innovation was sparse. It has had the same impact on stitching where its StitchLiner has become a success story for the same reasons. The machine requires training, but little experience to operate. It feeds from flat sheets, so there is no need for a section folding step and is suited to both digital and litho printed work. It will never match the throughput of a conventional saddle stitcher, but with short runs, it can comfortably exceed overall throughput, even with a top speed of 5500 products an hour.

A U-shaped configuration allows the machine to both fit in a restricted space and to operated by one man, loading and unloading as necessary. It will handle a 200 page job, one of the features that sets the StitchLiner apart from the same company’s booklet makers.

Increasingly, however, the humble booklet maker is taking on what might have been considered traditional saddle stitched work. The Horizon SPF 200 can include a creasing unit ahead of the stitching head so that when the product is subsequently folded, there is less need to force the paper. The L version of the same machine can also deliver an A4 landscape style.

The appeal is about speed of make ready and levels of automation and touch screen controls that essentially deskill the job. These advantages are large enough for printers and their customers to accept a job that may not have the sharp definition that comes from pre folded sections, but which is perfectly acceptable in the hands of the final reader.

Quality has improved through the addition of scoring in many booklet making machines. Duplo has this on the iSaddle machine, currently its flagship booklet making device. The new 600i booklet maker is almost identical. Both will deliver an A4 landscape product if necessary for example. Both will also feed from pre collated sets or from a digital sheet feeder. The difference lies with the sequence of folding and stitching and which is sold tends to depend on the background of the specific customer.

For the printer with an older saddle stitcher which can take 20-30 minutes to make ready, there are strong advantages in running a fast set up smaller unit alongside the older, faster machine. The Muller Martini or Stitchmaster machine takes the longer run jobs, the booklet maker the fast turnaround work. While with a modern saddle stitcher make ready is very slick, there is still a hassle from lifting a job that is running to rush through a couple of hundred copies of a new job for an urgent customer. It can be done, though in reality it makes more sense to keep a job that has settled into its run on the machine.

As similar ethos lies behind developments in perfect binding, where single clamp machines running PUR are well suited to digital print jobs and four clamp binders suit printers wanting to bring short run perfect binding in house to maintain control over a job and to keep profits in house. The costs of transport and set up on short runs is also out of proportion to the value in a job.

Again Horizon has made the running with the BQ 470 four clamp binder available as either a PUR or standard hotmelt machine. The latter is preferred for litho work, though coated papers may dictate PUR be used.

Gathering can be done on many stitching lines or any number of collators and the book block presented to the binder by hand or via a feeder for those needing non-stop production. If Horizon has been alone in this market, this is no longer the case. Last year, Italian company Risetec presented a four clamp perfect binder which could also apply end papers for cased in books, while at Hunkeler Innovation Days this year, Muller Martini demonstrated a small perfect binder that was in effect three single clamp binders in a single unit. Each clamp sits on its own independently controlled chain. It allows the dwell time after drawing on a cover to be extended as long as possible before delivering to a collection point for stacking. The first of the Vario binders has been delivered to a Swiss bookbinder which has found runs dropping to an average of 500 copies for litho and 150 for digital. There is also demand for single copy jobs.

Another approach to the question of coping with declining production runs, as with saddle stitching is to have a mid-volume machine and to invest in a short run device alongside it. It can be equally viable to buy a pre-owned Muller Martini or Kolbus to exploit the engineering of the binding section while hand feeding book blocks. The Kolbus KM200 is its entry level machine able to cope with fast changing formats (automatically where only the book’s thickness changes), while retaining the quality that Kolbus has always delivered. It will not introduce a smaller machine, arguing that digital volumes are rising to the point that Kolbus becomes interesting to smaller companies looking for a future proofed investment.

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