Sheet Feats

Sheetfed offset press advances have reached a level where neither sheet size—nor substrate—has to matter.

By Susan Friedman

Sheetfed offset press technologies have reached a nearly egalitarian state in which small-, medium- and large-size jobs can be handled in similar time with similar resources. But which format are most printers trying on for size?

A smaller sheet size that appears to have garnered appeal across printing markets is the 28˝ x 40˝. Achim Schmidt, manager for the packaging and label industry, Heidelberg, relates that the company's 40˝ Speedmaster CD, though introduced at DRUPA 86, took until the early '90s to really catch the sheetfed segment's attention. When it did, however, the press won customers not only in the carton printing industry but also in labels and commercial printing.

Sheetfed printers' approach to meeting shorter-run demands is not likely to translate into a steady downsizing. Current interest in sheet sizes smaller than 40˝ is mostly limited to prototyping and JIT production, Schmidt says.

"The industry still waits for a real half-sized press for folding carton," he adds. "Heidelberg is not ignoring this requirement, however at the moment many of our 40˝ customers take advantage of the quick size-presetting features of the CD 102 to go rapidly into the smaller sizes."

KBA recently answered to scaled-down sheet size needs with a 20˝ x 28˝ press, but Director of Marketing Bob McKinney sees this configuration, as well as the 40˝ machines, as more commercial application-oriented.

"The trend toward smaller sizes started five years ago and has practically ground to a halt," McKinney states. "Runs were getting shorter, and automation wasn't available on larger presses to achieve needed makeready and process speeds."

After automation for presses in the range of 51˝-64˝ was introduced at DRUPA '95, crew sizes, makeready times and speeds for small and large presses were finally comparable. As a result, McKinney estimates that only 20 percent of sheetfed presses sold today are as small as 40˝, while KBA's large format sales have increased four-fold.