It is crucial to have the correct setting for your rollers in your press. When your rollers are properly set, not only will they last much longer, but the press will also perform better. They enable faster and more stable color adjustments, quicker color changes due to a complete washing of the rollers, improved print quality and consistency. Since your press runs more efficiently with properly set rollers, you will actually use less power.
Here are some helpful hints in prolonging the life of your rollers:
Step 1: Check inking roll to inking roll.
First, put yellow ink on the roller. The yellow ink is used because it gives the best contrast and it’s easier to see the roller stripe.
How to check the roller stripe:
Open the guard and make sure the safety button is in.
Once the unit is marked with the ink, let the press stand still for 10 seconds. The compression stripe is formed when a press is still for more than 10 seconds.
Then move the press 1 to 2 inches to check the stripe.
The stripe should be easily seen. Use the gauge to check the setting and see if it is near Heidelberg’s recommended setting, which is typically between 4 to 5 millimeters.
How to adjust the roller stripe:
If the roller stripe needs an adjustment, use the standard adjustment tool and increase or decrease the adjustment.
The lifetime of the roller is shortened if you have incorrect settings because the constant flexing of the rubber generates heat. When the rollers are set correctly, the rollers are able to withstand a certain amount of heat. However, when they are set too strong against each other, excessive heat will be generated – destroying the vulcanized crosslinks of the rubber.
Step 2: Check the ink form rollers to the plate.
First, open the guard and inch the plate to the beginning of the gripper edge. Then lower the ink rollers onto the plate.
Now, leave it there for about 5 seconds to let the stripe compression form.
After the compression forms, release and then inch the press forward to check the settings.
There will be four stripe marks there from our four rollers.
If the dampening form roller is lowered, there should be five stripes.
It’s important to remember how many rollers were lowered onto the plate before checking because if one roller is not touching, only four stripes will be showing. This could result in adjusting the wrong roller.
You will want to complete these two processes for each printing unit.
The New Roller Check Assistant
With the new software on the Heidelberg press, we can choose to select the Roller Check Assistant, which cuts the process down to 5 minutes per unit while the manual adjustment takes 25 minutes to complete.
If the operator selects to use the Roller Check Assistant, the press will automatically print one dry, solid sheet.
Before we print the sheet, the press will lower all of the ink on the plate, let it dry for a few seconds, and then will print the solid sheet. The printed result will show the compression stripe.
Then, line up the foil with the printed result to check each of the rollers. This will also give us the optimum setting or showed any adjustments that are needed to get the press to the highest productivity.
This tool is great to easily check and see the rollers without the manual adjustment.
Whether you decide to manually adjust your rollers or use our New Roller Check Assistant, it is important to check and set your rollers to continue producing the optimum print job.
Check out Peter Halbert’s How To video on Checking and Setting Rollers below.
If you want to find out more, contact your Heidelberg representative or fill out the form below.