Automating the Cut

Printers often have mixed feelings about their operations. Prepress and press seem to get the lion's share of new technology development and capital budget. The bindery is sometimes last in line for new equipment, largely because processes like cutting and folding are regarded as necessary evils by management. But as print margins have compressed, every corner of the shop has come under intense scrutiny in a search for areas of inefficiency and high labor costs. And as presses have speeded up, traditional finishing can no longer keep up with delivery.

There's a lot of legacy equipment in the bindery and finishing area—in fact, many cutters, folders, stitchers and binders are obsolete. Statistics shared at September's Executive Outlook meeting, on the eve of Graph Expo, revealed that 70% to 80% of binding and finishing equipment is 10 years or older—much older than presses. Even among profit leaders, where presses are five years old or less, the bindery lags, with the majority of high usage finishing equipment—including cutters—eight years old or more. The bindery must become a focal point for improvement, with 86% of printers in a recent survey saying they plan to purchase new postpress systems during the next 18 months.

Cutting systems will be high on the list. Cutting paper lifts has always been a mostly manual process. There is the work of preparing the pallet of sheets to be cut, which involves picking the lift from the pallet and conditioning it before cutting. Then the operator moves the lift through the series of cuts needed for the work. Each cut involves moving the lift into position and against the backguage and into the clamp and knife. The backguage may have to be fine-tuned with a tilt or slight swivel. Trim must be removed from the cutter bed on almost every cut.

All the while, the operator is blocking the lift (or lifts) against the back-gauge. When the lift is finished, it's moved out of the machine and must be stacked down onto the finished work pallet. Movement is continuous and isn't light-duty. In shops with a high volume of sheet work that must be cut, that means a high labor input. Well over 50% of the labor involved in the cutting operation pertains to paper loading, unloading and movement through the cutter At the end of the day, it boils down to the number of cuts per hour that can be accomplished, and the number of operators required to make them. Heidelberg research bears out this postpress labor anomaly. While prepress and press have benefited from huge productivity gains, the bindery has experienced an overall 61% increase in labor costs since 1985!

Paper cutter vendors have done an admirable job in tackling this dilemma, automating many cutter functions to tackle this problem. Among the first enhancements to appear were computer-cutting programs able to store job-specific cut patterns and control some of the cutter mechanisms.

They walked the operator through the cut pattern and adjustments with the goals of making the process repeatable with greater accuracy and faster. But the basic movement of large amounts of paper remain a problem. Anyone who has watched a cutter operator will pick up on this immediately.

Heidelberg, with the Polar cutting systems, and Colter & Peterson, with Schneider-Senator and Baumann-Wohlenberg solutions, among others, address the problem with various approaches. Almost all have a de-stacker, and paper conditioning and loading system to automatically prepare paper lifts moving into the cutter from a pallet. The cutter will then have a gripper mechanism. The gripper (or grippers) will grab the paper lift and move it through the cut cycle without operator intervention. Some systems will turn the paper lift 90° or even 180° during the cycle. Lastly, when the cuts are done, the lift will be moved from the cutter air table and out of the cutter—usually to a stacker system to automatically move cut lifts onto a finished-work pallet, complete with pallet layer dividers. Paper lifts can be moved into the cutter by traditional front loading, or from the rear. This method works well for repetitive and high volume projects.

Heidelberg's Polar PACE (Polar Automated Cutting For Efficiency) was shown in the U.S. for the first time as a complete system last month at Graph Expo. PACE was designed to both increase cutter throughput and lower labor factors. This is done with the dual gripper mechanisms mentioned. Once the lift is moved into position in the cutter bed, it's hands off for the operator all the way. The main gripper will move the lift to the backguage, while the backgauge, clamp, knife and all other guides are also computer-controlled. (Direction for the system can be fed from JDF job production files.) An automatic trim removal mechanism eliminates the need to remove paper trim by hand. An eject gate on the cutter table opens after the knife makes the cut, dropping trim into a removal conveyor. When the lift (or lifts) have to be rotated for a cut, the unique rotating gripper will do this automatically.

This is pretty amazing stuff. The total automation of the process permits the operator to truly concentrate on the flow of work moving to, into and from the cutter. This can increase the number of cuts by up to thirty or forty percent. Polar's PACE is fitted to their 155 XT guillotine cutter. Polar offers a full auto-cutting system called the L-R-P-(137)-T. It uses the Polar Transomat material handing component. The Transomat stacklift will pick precise paper lift quantities from the pallet, and jog (and optionally weigh) the lift for total accuracy. No more overs or unders. Once in the cutter, PACE does the rest. Transomat E does the unloading and restacking on the finished work pallet. This is not an inexpensive system. A complete auto PACE and Transomat combination can run a half-million dollars. But the benefits are enormous and justify the investment.

Rob Kuehl, Heidelberg USA's postpress development director, says that a complete PACE/Transomat system can save one operator in two or three-shift operation. The ROI can come in at less than three years, which is fairly reasonable. In addition to the increased throughput and labor savings, cutting accuracy is improved, and any operator injuries associated with the constant bending and lifting of paper are virtually eliminated.

Colter & Peterson, Paterson, NJ, sells a wide variety of guillotine cutting systems, including Saber, Prism, Inpro and Wohlenberg. For automating cutters, Colter & Peterson's range of offerings extends from the relatively simple C&P Microsystems—these can be retrofit even to rebuilt cutters from the company's inventory—to fully integrated guillotine systems based on cutters with Baumann Maschinenbau Solms and Schneider Engineering to provide front and back-end workflow automation. Baumann's integrated system starts with the BASA Automatic Jogging System.

BASA de-stacks partial sheet layers from the pallet pile, then fans and aerates them. This layer then moves to the jogging table, and it's aligned very precisely. An air-expulsion roller presses out any remaining air before the lift moves into the cutter table via gripper. BASA can be fully automatic, or semi-automatic to allow the operator to give that extra bit of hand-conditioning to very badly formed piles on the pallet. The systems curved gripper path takes the jogged lifts into the rear table of the cutter just in front of the backguage.

Baumann's Automatic Positioning System (APS) takes over the function of turning the pile for the cut sequence. Using two alignment pushers, one at the backguage and the other at the machine base, the pile can be auto-turned either 90° or 180°. APS will not perform all cuts automatically. Apart from the four-side trim and dividing cut, other cuts are done manually. APS provides accurate alignment of the pile during the sequence. The system is completed with a Baumann unloader. Single or divided cut lifts are taken out of the cutter bed automatically, while multiple-cut lifts are manually pushed onto the re-stack area by the operator where they process onto the pallet.

Another key component in an automated cutter workflow system is a pile-turner. Pile turner's eliminate huge amounts of labor needed to turn and condition a pallet-load of paper. Turning systems will not only (easily) turn a full pallet, they will both vibrate the paper, and aerate the entire pallet by moving blowing air through the complete pallet one section at a time. The end result is a fully-conditioned pallet without all of the heavy-lifting.

Schneider Engineering also offers full cutter automation through Colter & Peterson. Schneider's systems feature a stacklift and paper conditioning loading system. Once in the cutter, a robotic arm will turn and align the lift for the cut pattern. Schneider also offers an auto knife lubricating option. These complete cutting systems have revolutionized the high-volume sheetfed environment.

By looking at cutting in the bindery as an opportunity to redefine the workflow involved in the operation, guillotine cutter manufacturers have vastly improved the cutting process. Significant amounts of labor (and cost) have been saved, accuracy is better, injuries have been reduced, and overall throughput has taken a quantum leap forward. Finally, the bindery is starting to keep pace with prepress and press in systems automation and the ensuing workflow improvements.

Colter & Peterson's Prism and heavy-duty Saber paper cutters are now distributed by xpedx Printing Technologies. (xpedx also distributes Challenge and Perfecta cutters.)

Each Prism product is equipped with an air table with built in blower. The air table provides a cushion of air that floats the lift so even the heaviest material can be moved, turned or aligned easily. A computer controls the air on the cutting table. The air turns on automatically when the back gauge moves in reverse and turns off when the back gauge moves forward. The air table can also be turned on or off manually.

Baumfolder programmable Baumcut 26.4 and 31.5 cutters can be integrated with air tables and joggers to create a semi-automated materials handling trimming systems. Baum's 31.5´´ is a heavy-duty, fully hydraulic cutter, with push-button programming, that can store up to 99 programs with 6,464 cut steps.

Safety features include infrared beams, two hand timed cut release and covered rear table. Noise is minimal because the motor runs only during cutting operations.

Programming is automatic. The operator cuts the first lift manually, and the cut pattern is stored for continuous repeat. Knife changes are simple, says Baum, with adjustments done from the front. A built-in table light and optical cutting line indicator yield more precise cutting.

At Graph Expo last month, Akiyama announced it would begin distribution of Micron cutters, manufactured by SWD. Using computer controls made in the U.S. and European hydraulics, SWD says it is the second largest producer of paper cutters in the world, shipping more than 2,000 units per year. It recently received ISO 9001 certification.

ONLINE: www.akiyama.com, us.heidelberg.com, colterpeterson.com, ryobi.xpedx.com, baumfolder.com