How can printers ensure proper calibration of their manual press?
Ensuring proper calibration of your manual press begins with routine and regular monitoring, and upkeep when necessary. Always remember, prevention is better, faster, and cheaper than repair.
The key is to know your machine. When your equipment is out of calibration, it will show. Your platens will not be giving you similar output, and you will be forced to choose heads based on the ink color. If either of these is the case the best place to begin is with the proper tools. A few variations of levels and wrenches will be necessary.
For proper calibration, I would suggest doing it during off hours and plan for about four hours, give or take.
Start with the best possible environment—a level floor.
When ensuring calibration, the first item to check is the center shaft. Once this is level, and everything has checked out you will move on to the platens. If there is an issue with your shaft, the solution will be in the elevator bolts.
First, find the most level platen to use as a guide. Then, address the remaining platens to confirm they are level north-south and east-west. The bolts found underneath the platen will allow you to make any necessary adjustments. Once adjusted it is time to tighten the bolts. While tightening them, keep an eye on your level to confirm you are not throwing your adjustments off. Recheck your center shaft to confirm it is still level and readjust the elevator bolts if necessary. A second pair of eyes at this point can be a huge help. This will allow one set to focus on the level while the other is retightening.
Next, make sure all your platens are equal height. Utilizing your flash unit, take your guide platen along with your levels and with your flash unit in its proper position, (over the platen) adjust it so the platen fits snuggly up under it. You will want to be able to move the platens, but otherwise, you want it as snug as possible. Our objective is to make sure all the platens fit in that same position with your flash as the measuring stick. Move on to the next platen by addressing its levelness then its height. Continue this until you've checked all platens.
Now, it's time to adjust the off-contact. Before beginning, choose a screen that is even and flat corner to corner. At this stage, you will be making sure your off-contact is level. Once your first screen has been properly adjusted and is level in both directions continue to the remaining stations.
Lastly, you want to reset your flash by the manufacturer’s instructions and make sure it is level anywhere on the floor.
Your press is calibrated! The center shaft is level, your platens are level, all your screens will be level in the printing position, and your flash is level to all of your platens. Having everything level will ensure faster printing with less pressure, deflection, and more consistency.
This depth of maintenance should only be necessary on occasion, but by checking your presses routinely and giving them a tune-up from time to time, you should be able to ensure calibration.