This is very strange, I’ve never heard of a noticeable density shift from one day to the next, and the way it goes back to normal after a few more prints… That sounds like ink in the dampers and ink lines, and I don’t suspect the print head would cause what you’re experiencing.
After reviewing your order history, I see you last purchased Piezography Neutral inks in June 2014, and a set of 9800 refillable carts in November, are these the same carts and inks that you’re currently using?
If so, have your prints been correct/consistent over the past year, and recently started coming out dark after startup?
Did you replace the capping station, dampers and wiper blade before or after this problem started?
Did you replace the parts yourself, or have an Epson tech come and do the work?
Does your printer’s pressure pump turn on while your printer sits idle?
How often have you been agitating your ink cartridges?
How often is the printer used vs. how long does it usually sit unused?
What are the temperature and humidity levels in your printing environment?
If your nozzle checks print the same shade gray in multiple channels, including the LLK/PiezoFlush channel, this makes me think you have ink mixing between channels, which could also cause poor quality output until pure/correct density ink starts flowing thru the head.
Have you ever cleaned the bottom of the print head, following our instructions? If not, printer cleaning information can be found here: http://www.inkjetmall.com/tech/content.php?133-Printer-Cleaning-and-Preventative-Maintenance
Please let me know, and I will try to help.
Best regards~ Dana :)[/QUOTE]
My printer had been sitting idle for about 18 months with flushing fluids. About 4 months ago installed new K7 inks. At that point, I replaced the main pump (because an error message indicated it was falling), dampers, and the capping station myself. I also switched from Studio Print to the Quadtone RIP, and bought a set of Ink Jet Mall cartridges to replace my older carts. The printer has not printed consistently since then. For a couple days it prints normally, then I get the odd nozzle check pattern and abnormally dark print. As I mentioned, the print will get lighter as I continue to print the same file, but nozzle checks will continue to show many clogged nozzles that vary in position with every nozzle check.
I agitate the cartridges if the printer has sat idle for a week.
My studio space is new and is heated with a radiant slab, so the printer has been in consistent temperature and humidity.
I also was thinking the inks must be mixing between channels, but how is that even physically possible if the dampers are securely attached to the print head? In some way it seems like ink is flooding the print head, like there is a constant back pressure problem.
I have cleaned the bottom of the print head several times, but ink builds up much more quickly than I ever encountered in the past.