Consistency in press operations requires a more concentrated effort from the press operators in understanding the theory of the process and following the same procedures each time they set up and run their respective presses.

This can be effectively accomplished by the development of a checklist of the steps to follow and should be generated by the press operators and supervisory personnel themselves. Operator compliance will be improved if the people involved write their own procedures. Not only will this checklist ensure more consistent operations, it's also a valuable first step in preparing your operation for ISO 9000 certification or other customer quality certifications.

The following is a sample list of procedures in a consistent press-run plan:

1. Examine the job ticket. Included should be the layout, artwork, specification sheet, mounting documentation, mounter proof (strongly recommended), and the press-run condition sheet.
2. Bring cylinders out to the press. Examine plates for proper bevel, seal and possible defect. Verify cylinder repeat and gearing. Check for wear on bearings and gears.
3. Determine color order and anilox placement.
4. Install plate cylinders, making sure they are free-spinning before locking down bearing caps.
5. Run the decks in.
6. Set dry register.
7. Mix inks thoroughly before adding to the sump, and verify from the specs that it is the right ink system. Sheet and verify that the running conditions of that system are known. Measure viscosity if solvent or pH if water ink. Never apply ink to the anilox roll without knowing that it is in control.
8. Pump inks into decks and properly set the doctor blades. Minimum pressure is required for the best efficiency and wear.
9. Verify that the inks are in their proper ranges before settings are achieved.
10. Run the press at a slow speed to see print but fast enough for good transfer of the ink system used.
11. During run-ups, adjust web tension and edge guides.
12. Set up one station at a time. Achieve full print on the substrate. Determine ink setting, then impression settings, on each deck.
13. Put all colors together and register.
14. Speed press up and note print. Adjust register if necessary. Determine lightest possible setting on all stations (defined as kiss).
15. Colormatch and densities can be worked on during run-ups only if the setup stock is a material identical to that job.
16. Verify substrate, color, position and separation and begin to run the job if approved.
17. Document all press-run conditions and any problems and/or fixes if they occur. Also keep a running record of ink conditions for consistency.
18. When job is complete, wash-up can begin.
19. Clean one station at a time. Stop pump, drain ink and remove return hose from sump. Remove blade and thoroughly clean the anilox roll. Pans, pumps and blade are to be cleaned after the anilox.
20. When the press is washed up, verify that all information for running that job has been documented and placed in the job jacket.
21. As the press is running, production information regarding the next job can be examined and preparations made.

The procedures outlined above are for a standard mechanical press with integral plate cylinders. There will need to be some modifications if the press is more automated or sleeves are used—but the theory is the same. If standard operations and procedures are followed there will be fewer variables to be controlled and press runs will be more consistent, downtime will be minimized and better quality will be achieved.

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