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As appearing in The Seybold Report - June 29, 2006

Article prepared by C. Clint Bolte, C. Clint Bolte & Associates, Chambersburg, Pennsylvania. For additional information please call 717-263-5768, fax 717-263-8945, or e-mail to clint@clintbolte.com.

Roll Sheeting Has Come of Age

Packaging printers have been sheeting SBS board stock from rolls on off-line, stand alone units for half a century. Sheeting commercial paper from rolls has been a viable process improvement for sheetfed printers since the mid-1980s as the manufacturers designed smaller more compact units. And yet acceptance by mainstream general commercial sheetfed printers has never reached any appreciable degree of its potential. New interest has been generated in the recent couple of years, as the long perfectors have become mainline tools for more general commercial printers. As a matter of fact the number of 8-12 unit sheetfed presses installed without an in line sheeter is becoming more the exception than the rule.

In the old days "the difficulty of achieving accuracy of cut and squareness" from an in house sheeter was possibly a concern. There is little doubt that if a printer was going to commit north of $5 million to buy a long perfector there is not a shroud of doubt about the quality of the sheet being delivered from the on-line or in-line sheeter.

Lets look at the features of the on-line versus the off-line sheeter as far as advantages and disadvantages. The on-line will save the labor of an off-line operation along with pallets and storage (regardless of how brief) of sheeted product waiting to move to the assigned press. The on-line does not need the stacker that the off-line requires. On the negative side the on-line unit requires sophisticated electronic integration, a dancer accumulator to adjust for fluctuating press speeds and can provide only grain long or short but not both. It achieves this grain direction by delivering the stock straight in as grain long for the production of full size A4 signatures. When stationed at a right angle to the press, it delivers short grain stock for the smaller trim book signature.

The off-line unit can deliver both short and long grain stock simply by shifting the position of the pallet receiving the sheeted product. The on-line unit delivers one sheet at basically press speed. The off-line unit can cut 60" wide, which means it can slit 2-out of a 56" wide roll to deliver dual stream 28" by 41" sheets to a pair of pallets next to one another. While the on-line is limited to the speed of the press or 13,000 sheets an hour (430 feet a minute), the off-line machine can run three times that speed (up to 1,300 feet a minute) plus deliver 2-out.

While both on- and off-line units will be an investment in the $450-500 thousand range, a single off-line sheeter running five ten-hour shifts can provide stock to keep three sheetfed presses busy round the clock six days a week. Or stated another way a single shift on the off-line sheeter can provide stock for up to eight press shifts. Instead of feeding only one press, every press in the stable can receive stock from the off-line sheeter.

The two factors driving the decision for sheetfed printers to buy roll stock and sheet their own are (1) the cost of the roll stock versus converter sheeted product and (2) the ever quicker turn around times required to deliver the finished product. The $30-60 per hundred weight (CWT) savings is typically this roll versus sheet differential.

With more and more clients insisting upon just in time (JIT) schedules, printers are examining every process element to attain control and reduce lead times. "Full service" has never before taken on such a broad context for its definition. Depending upon make orders at the mills and the resulting cyclic demands at converters, lead times for sheeting can reach a couple of weeks or even more. The recessionary pressures of the recent couple of years tend to keep that lead-time down. The economic turn around now under way will increase demand and could lengthen that critical waiting period. This factor could make the consideration of this equipment a very timely one.

It is true that the specialty printers have tended to have in-house sheeters. These include packaging (printing on board), label (printing on coated one side) and envelope converters. The two things these firms have in common are stock standardization and the need for a variety of sizes, which is satisfied by the different roll length cutoffs. And yet many of these firms deliver 4-6-8 color products with quality as demanding as any commercial shops.

The economics of the investment certainly must be considered. The areas of savings are the sheeting charge by the mill or the converters, the extended time needed for this extra outside service, and the extra warehouse space needed for sheeted skids rather than roll stock.

The sheeting process will incur spoilage. In the 1980s paper board surveys indicated that 3.6% would be an average while 70% of the respondents experienced 2% or less sheeting waste. In recent years with the improved electronic controls and enhanced technology incorporated in these sheeters, users target 1% spoilage and some claim to come under that figure. This improved spoilage performance is realized despite the product shifting trends of shorter runs, more frequent changeovers, and multiple handling of rolls.

The warehouse space savings is certainly not an incidental advantage. The optimum operation would buy 50" diameter rolls to be sheeted. They would stack 40" wide rolls five high or 60" tall skids four high in a 25-foot high warehouse (22 foot clear under the sprinkler heads). Precut skids are stored in racks possibly four high or two high if on top of one another. With this scenario, calculations would show that roll stock to be sheeted would save 50% of the floor space of precut skids. In reality the square footage savings is more like 20-25% due to aisle ways and work in process storage requirements between the sheeter and the presses.

The Operations Vice President for York, Pennsylvania's Strine Printing, Dave Kornbau said his firm has been sheeting rolls in house for four years. They now have three different sheeters manufactured by three different suppliers. These roll converters are running full out to provide sheeted stock to their twelve sheetfed presses that are running round the clock six days a week.

Their most recent press, a MAN Roland XXL, installed in November 2005, requires an unusual 80" cutoff. This is provided by their off-line Maxson MDH sheeter. "Currently 95% of the stock printed has been sheeted in house," remarked Kornbau. He feels that printers should realize 3-4 year payback as a conservative return on this investment if they have sufficient paper volume.

Printers consuming 80 tons of paper a month can realize a ROI on an in-house sheeter. This is the equivalent paper for production of two full shifts on a 40" press that nets 10,000 impressions an hour at the industry norm of 43% run time. While used sheeters are readily available, the unusually low prices carry a caveat. The analogy is similar to the cheap prices quoted for used sheetfed presses manufactured prior to the mid-1990s. And that is, the latest electronics that lead the way for very fast make-readies and many automation features are simply not available as upgrades on older roll converting units.

In previous years the sheeter manufacturers would primarily be exhibiting at the Converting Machinery Manufacturers' (CMM) trade show. Because of the increasing interest by sheetfed printers as well as their partnerships with press manufacturers in showing on-line operations, these suppliers will be at the Graph Expos and Print equipment shows. A few of the well known sheeters are Bielomatik, Jagenberg, Lambs Gray, Langston and Maxson. If the prospective printer cannot wait for the Graph Expo 2006 October 15-18, s/he should call Brent Burdick, Maxson's Vice President of Sales and Marketing, at 401-596-0162 (maxsonautomatic.com) and Ron Pueshel, USA President of Bielomatik-Jagenberg in Windsor Connecticut at 860-640-0500 (biel-jag.com) for product literature.

Article prepared by C. Clint Bolte, C. Clint Bolte & Associates, Chambersburg, Pennsylvania. For additional information please call 717-263-5768, fax 717-263-8945, or e-mail to clint@clintbolte.com.