Wednesday, May 12, 2021

It's Dead, Jim

Short version: after nearly a decade of service, my 7900 has reached the end of its life. Printing had become increasingly challenging in recent months; clearly some of the machine's components were no long operating up to par. But I was always able, with various levels of effort and wasted time and ink, to get good  nozzle check on all channels. That is no longer true. The longer story follows.

On 3 May I prepared a couple of image files for printing. One would be and black & white image on an 11 x 17 inch sheet of Canson IFA Baryta, using one of my last remain sheets of this discontinued paper. It's been a favorite for years. The second would be printed larger, on a 17 x 22 inch sheet of Epson Exhibition Fibre. I prep'd the files in the usual way, and then began what I knew would be an ordeal getting the printer ready. I'd last printed in mid-March, about three weeks earlier.

The first nozzle check print showed showed all channels at 100% except VM, which had a small missing nit in a corner, and minute "displacements" or deflections on the sides of the LK channel. I first noticed this displacement back in December, 2020, but I could see no obvious issue with the prints, so I'd come to ignore it on later nozzle checks. If I could get all nozzles firing in all channels, I'd continue with printing and get the usual excellent results. I ran a standard cleaning of the C/VM pair, did a second nozzle check, which showed problems with O, LC, LK, and LLK missing entirely.

Before I finished I'd run a total of 15 nozzle checks and print purge files (which prints a business-card-sized patch of a single ink) for several channels, over the space of three days, in total consuming about six hours and leaving me very cranky (don't ask my wife). I removed and cleaned the wiper (which needed it, as it turns out). I had to replace the maintenance (waste ink) tank and two ink cartridges; fortunately I had a new ones on-hand. When I'd start to feel like I might be a danger to myself or things around me, I'd shut off the lights and walk away, hence the three days. My normally low blood pressure probably wasn't for a lot of this period.

In the end I had a good nozzle check. Except for those LK displacements, as shown below, with the second scan enlarged for detail.

  

As mentioned, I'd been seeing this for a while, and based on past results didn't consider it a problem. As it turns out, I was quite wrong. Below is the first print I made, of the B&W image.


Those bands pointed out with the tiny red arrows are about .75 inches (2cm) from the printed edges, with the image being close to the edge of the paper. This sent me down the hours-long gopher hole of troubleshooting the problem.

A nozzle check looked fine (except for the LK displacements). I made a few partial test prints on junk paper and learned little, with one interesting exception: If I made a small print in the center of a larger sheet, such that the unprinted borders were several inches wide, the print looked fine. I've thought long and hard about this and have come up with no reasonable explanation, especially given the root cause of the problem (keep reading--I'm almost done).

Finally, I printed some purge files for the black and gray channels, PK, LK, and LLK. PK and LLK looked fine, but LK showed a wide band, as shown below.

It seemed pretty clear that the displacements in the LK channel had progressed to the point at which quality prints were no longer achievable. Looking back through older nozzle check prints I found the first hint of these displacements in late 2020. Comparing that to a current check it's clear the deflection has increased. My theory is that when tiny, whatever impact the displacements had on print quality was covered by later passes of the printhead laying down ink over the area where banding happened. Just a WAG, but I can't think of another explanation, and in the end it's irrelevant anyway.

Since I had nothing to loose (but a little time) I ran through the head alignment procedure one normally does when setting up a new machine (or when banding issues arise). This had no impact.

Just a sampling of head alignments, failed prints, and other tests.

So, that's it, the end of Life With A 7900. I'm not happy about it, but I'm feeling surprisingly serene, maybe even a little bit relieved. The machine produced first-rate prints, and a lot of them. It paid for itself many times over, although it often wasted more of my time than perhaps it was worth.

I have mixed feelings about Epson; the 7900 punished me for many of the prints I made. There were buggy drivers (which got fixed), a somewhat weird UI (which I got used to pretty quickly), more wasted ink than I care to recall. I understand some, perhaps most, of the hardware issues (clogging or other ink delivery problems) never happened with later generations of the machines: a friend with a P7000, which does not see frequent use, doesn't even bother to run nozzle checks; he just prints, and the results are excellent every time. With later models Epson clearly fixed many of the x900 series's issues, proving that nothing is so screwed up that it can't serve as a bad example.

I've got a very busy year ahead of me and I'm not feeling any immediate rush to replace the 7900 (although a couple of my regular clients have expressed a hope that I do). I have a lot of research to do on the path to choosing my next printer. As a former U.S. President and "reality" show host said all too often, "We'll see what happens." But one thing is certain: I won't be blogging about it!

If you've followed my increasingly infrequent (and irrelevant) postings here, thank you. I hope you found them useful, and failing that, maybe at least a little bit amusing.

  --Jay