Press Life Preserver

August 2001

multipage

For minimum day-to-day operation and clean-up hassles, follow these five steps to long-term letterpress maintenance.

by Jessica Millward, Associate Editor

1. The line-up

The path to relatively painless letterpress printing begins before the operator even reports for duty. How the press's daily "To Do" list is constructed plays a major part in the number of cleaning and changing procedures required, and therefore serves as a great opportunity to conserve print "energy." Ko-Pack Service Engineer Pat Bowdy counts job planning as the printer's first shot at the shortest downtime possible. He recommends configuring job sequence to minimize color changes, as well as planning ahead to use solvents compatible to proposed inks and rolls.

2. Component concerns

The mechanical upkeep of a letterpress affects its longevity, its performance, and determines the level of difficulty involved in press clean-up. Dave Manley, printing technician for Nilpeter, enumerates several key parts to keep in mind. First, he suggests, "The ink rollers must be checked weekly for proper settings and condition. Worn rollers must be replaced as soon as possible, because worn or mis-set rollers will take much longer to clean up than rollers in good condition and [that have been] set properly."

Manley also believes strongly in keeping a close watch on the wash-up tray, as well as keeping the blade clean and in good shape. Bowdy's words of maintenance wisdom focus on procuring rubber rolls compatible with inks and solvents being used, as well as rebuilding print heads every six to eight months.

3. Clean getaway

To really cut down on downtime, printers should form a very clear picture of precisely when and where they will clean inking units. As Gallus Sales Manager Bob Yates points out, many jobs solely use four-color process with an additional one or two specific PMS Colors, and these CMYK stations normally don't need to be cleaned between jobs. He states, "The specific PMS color matches are the only ones that need to be changed and cleaned up." Yates also reports several of his customers keep additional letterpress inking units handy, so a clean one can be put on press immediately, and the soiled unit can be cleaned off-line.

4. Who's on first?

After determining the optimum job schedule for any given day, it is vital to communicate that roster, in complete detail, to the operating team. Manley notes, "There must be procedures in place to dictate who is responsible for different tasks involved in the clean-up and set-up of a job." Apprising the press operator and helper of their specific duties, and the order in which they are to be performed, leads to significant clean-up and changeover time reductions. In addition, Manley attests, with this method of operation, "the chance of something being missed is minimized."

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