9890 LC and VLM nozzles - Recoverable?

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#1

I’m hoping someone who has experience with the 9890/9900 head failures can help me determine whether the problem I’m having with the VLM and LC nozzles is recoverable, or if the printhead is done.

I’ve attempted to attach a photo of recent nozzle checks. The upper print is prior to attempts to clear the nozzles and the lower is after. The LC nozzle pattern is pink on the lower print, because the LC cart was replaced with one filled with Piezoflush.

I have performed all of the steps in the Inkjet Mall cleaning video, and parked the head over a folded paper towel saturated with Piezoflush for a few hours. (not 24, yet!) The LC cart was replaced with one filled with Piezoflush and purges prints were performed until the LC ink was flushed. The wiper was replaced about 4 months ago when we first had trouble with a couple of nozzles. The capping station and dampers have not been replaced. We have used only ConeColor Pro ink for the past two years, and Epson before that. Only the cleaning functions available from the main menu have been used.

As one can see, progress has been made in clearing the VLM nozzles, but the LC has hardly changed at all. I don’t know if that’s telling me anything about the condition of the capping station or not, since these colors share one. The pattern of LC dropped nozzles has remained the same through a couple of weeks of attempts to unclog.

I don’t want to go through the effort and expense of replacing more parts if it’s a lost cause. Is there anything else I should try?



#2

It’s very hard to see with this resolution.

Can you post again?

best,
Walker


#3

OK - Having a little trouble getting the uploader to work. When I try to upload anything that seems reasonable, it gives me the red exclamation mark. I know it’s hard to see. I might have to get a better image. Let’s see if this works.


#4

Ok. I can see now.

The VLM is showing CLASSIC delayed fire in the middle. This is a head that is going. It’s not a clog (because it’s firing all the nozzles) but the nozzle electronics are slowly giving way (creating the delayed fired).

The end result will be a total failure of that channel. Channel pairs go together and the VLM and LC channels are a pair so this is a second indicator of shorting nozzles (not clogs).

best (or, I feel your pain rather),
Walker


#5

Thanks Walker - Yes, painful, but at least I won’t keep struggling with it. I appreciate your quick diagnosis.

The question is what to do next. B&W piezography is not of much use to Dana, since her artwork is not B&W, and we all know the math on replacing the printhead vs buying a new printer.

Thanks again,
Owen