In an ideal pressroom environment, nothing would go wrong and you’d get consistently accurate jobs from your offset press. Unfortunately, we don’t work in this imaginary perfect pressroom. As a result we sometimes end up wasting materials and losing time.
Your best bet is to learn more and be prepared to handle problems the moment they arise. There are useful training and education tools available that will help you stop wasting and start earning more profits.
If you wish you had an expert on hand who can tell you how to handle these types of problems, you actually do! We’ve pulled advice together from one of our onsite experts, Lloyd DeJidas, Director, Graphic Services and Facility Manager, Printing Industries of America, for Five Best Bets for Your Offset Press:
- When troubleshooting on a lithographic process, first and most importantly, be sure to accurately identify the problem. I see many printers resorting to excuses like “These inks should run on any stock,” or “We don’t have time to test things,” rather than trying to identify the root cause. When you know the problem, you can find a solution and help avoid a future incident.
- Determine all possible causes of the problem, such as press, materials, or human error. Ask what has changed and quickly organize your data to verify potential causes.
- Analyze the plate scum line and determine if you have the proper ink and water balance. The scum line will tell you if your:
- Skewing roller is set properly
- Metering roller is performing well
- Dampening system is even from side to side
- Get an accurate measurement of fountain solution, blankets, and rollers. With the many interactions and variables on the offset press, you need to have the right instruments:
- Meters measuring p/H and conductivity assure that the fountain solution has been mixed properly and will indicate when the fountain solution has become contaminated and should be changed to avoid print quality deterioration.
- A roller durometer indicates when the ink or dampening roller has become too hard, which could cause roller streaks.
- Regular measurements of the blanket with a packing gauge will indicate when a blanket has lost pressure due to compression set and needs repacked.
- Measurements with a dead weight micrometer confirm that the blanket has been made to proper specifications.
- Always remember: If you can’t measure it, you can’t control it!
- When a printing problem arises, determine the root cause by testing your paper and ink. These are some of the tests to perform:
- Inkometer readings measure if the ink tack sequence is correct for proper wet ink trapping.
- Grindometer measurents ensure that the paper has been milled properly.
- Calibrate abrasion testers indicate that the inks have set and will have the proper scuff resistance and durability that your customer will be pleased with.
Studying best offset practices like these will help you take control and optimize your pressroom. If you want efficient hands-on training for offset printing, Lloyd will also lead the training workshop Extreme Offset: Troubleshoot, Control, Optimize, hosted July 23–25, 2013, at our headquarters in Pittsburgh, Pennsylvania.
You will learn proven techniques to measure, troubleshoot, and optimize press performance in our onsite printing facility and Paper and Ink Laboratory. Registration is open for this course.
For more information and resources on offset printing, visit our Center for Technology and Research at www.printing.org/ctr.