7600 Banding Problem



I have an Epson 7600 printer I bought used. It has both vertical and horizontal banding problems. It was originally purchased in 2003 by a NASA facility in Virginia. I have no maintenance information on the printer. When I received it, it had Epson pigment inks installed. I ran a nozzle test on it and it was perfect. I have since installed piezography inks to produce positives and negatives for palladium and copper plate gravure printing. I didn’t notice the banding issues until I printed a negative for making a palladium print. (I have included a positive of the palladium negative, a diagnostic nozzle test and an ink separation image. The positive and the ink separation image were printed on Pictorico transparency film. All were scanned on an Eversmart Pro flatbed scanner at 600 dpi and reduced to 300 dpi to reduce file size.)

I have performed the following maintenance procedures on the printer:
From the SelecType menu: I performed the UNI-ALL and BI-D ALL alignments. I tried the Paper Feed Adj from -1 to +1. I reduced the Suction to Low and set the Platen Gap to wide. None of this helped.

I downloaded a Field Service Manual for the 7600 and: From the Diagnostic menu I performed a BI-D adjustment and executed the CopyParam function to save the values. I purchased a tension gauge and set the paper feed tension and the carriage feed tension. I performed the +T&B alignments to set the Top, Bottom, Margin and V(length) distances for the paper feed. This helped somewhat. I have ordered dampers and a new wiper for the head. It is obvious from the Diagnostic Nozzle Test there is a problem, but I can find no instructions on how to ‘read’ the printout to analyze the problem. Any assistance or advice you can provide will be greatly appreciated.

I was able to upload files but cannot figure out how to attach them. Can you provide additional instructions? Thanks. Cheers, Charlie