The device to lift the keys works but it does cause a problem if you try to lift the keys too high. The device has a tendency to bow in the middle causing the keys to get out of alignment. You only have to lift the keys enough to slide the foil out, 4mm's max. The problem is that by the time people realize they need to clean the foil there is so much ink on it that you have to lift the keys higher than that to get it out.
The keys are laser cut and matched to each other from the moment they are made at the factory. They are not interchangeable. The process used to make the dense spring steel they are made from was one of the most difficult processes the factory performed when making these machines. The blank steel used to cut the keys from was pressed 7 times in a 10,000 ton hydraulic press to condense the steel, once this was done the blank was laser cut into individual keys which were numbered and stacked in matching sets. If one of these stacks was inadvertently knocked over they all were thrown out.
To make the ink fountains, special gauges were used to align the keys, the space in between each key can be no more than .01mm and Renax grease must be used on the edge of each key. They must be set perfectly parallel to the fountain roller. Yellow ink was put in the fountain and the keys were manually closed until an even thin film of ink was seen on the fountain roller. Once the preliminary setting was done every other key was opened all the way and the rest closed, then the process reversed, this was done 4 times and the keys were set back to zero. Then the keys were manually set again until a thin film of ink was seen. This process went on until there was no more movement need to maintain the even film of ink. This was done on a special jig before the fountains were mounted on the press.
Once the ink fountain was installed in the machine, test printing was performed to see if the keys were set properly. A solid was burned on all units and black ink was used for the test. The machine was pre inked for 100 revolutions, the stroke was then set to 40 with the ink keys on zero. 150 sheets were printed at this setting. From unit to unit the overall density must be between .05 and .20. For each unit from zone to zone the density variance could be no more than .05 and from O.S. to D.S. across the sheet it could be no more than .1. If any of these were out, the fountains had to be set in the press until they were met. Each time you print to check the settings you must pre ink 100 revolutions and print another 150 sheets.
I know all this because I built them in the factory for two weeks.
In the field the fastest I could make an ink fountain meet these specifications with proper tools was 2 hours per unit. This was one of the most difficult jobs I performed in the field. I would rather replace cylinders than do this. My guess is if you asked anyone who worked on these ink fountains they would tell you the same thing.
Everyone I know tried to shortcut the process, myself included. But I found the best results were always achieved if you did the whole process from start to finish with the tools and gauges.
In short, take care of the ink fountain. Keep it clean on top and underneath.
