Epson 7900 - yellow channel problem

[Dan Wells]

I've had a 7900 for about five years... Due to the kind of photography I do (I'm a fine-art landscape photographer, printing my own work), the printer inevitably sits while I'm in the field, and it has previously always come back to life after a few nozzle cleanings. After a 6 month absence, I can't get the yellow channel back - about 1/3 of the nozzles are gone, and it's the same ones no matter how many cleanings I do (including one SuperSonic cleaning). I've also tried one windex wipe of the printhead, and printing a large yellow square to exercise (exorcise???) the nozzles.  This could either be a really stubborn clog (but nothing I've done has affected it at all) OR some actually dead piezo units. Anything more I can do, short of putting a new head in at close to the cost of a printer? All 9 other channels are perfect...
Alternatively (and probably more attractively than putting a $1000++ head in a 5 year old printer), I could sell this thing to someone with an interest in Piezography and replace it (probably with a Canon Pro 2000 - I don't want to have another Epson sitting while I photograph). I have a show to print that needs to hang in a month, so I have to do whatever I do relatively quickly.

Dan

[Mark D Segal]

Using Windex on an Epson print head is not a good idea. If I were you I would call Epson and discuss the problem with them, see what they say, then make a decision what to do next on that basis.

[datro]

Dan, if the missing nozzles are contiguous, if they are showing up in the middle of the pattern, and nothing you do changes the pattern, your head is gone.  Not a clog but a piezo electromechanical failure.  This is based on my previous experience with my 7900.

Dave

[Garnick]

Hi Dan,

I had a lot of experience with the 9900 and Epsons Service department.  I bought the printer in early 2010 and sold it in Jan. this year.  Had a new head installed Jan. 2016.  However, other than Marks advice I will not wade into the new head pool just yet.  Could you please send a scan of the Yellow nozzle pattern.  That might shed enough light on the situation for us to make a more educated guess.

Gary

[Dan Wells]

Here's the test pattern -  the iPhone photo is not perfect, since I couldn't quite handhold the macro indoors - but it shows the gaps (which have been consistent through many nozzle checks - both bigger areas have remained exactly the same). I've done probably 10 normal cleanings, 10 pairs on that channel (running prints through in between), a couple of service mode pairs cleanings and a SuperSonic clean - none of them changed the big areas (the additional little gap may have changed a bit).

Dan

[Garnick]

Here's the test pattern -  the iPhone photo is not perfect, since I couldn't quite handhold the macro indoors - but it shows the gaps (which have been consistent through many nozzle checks - both bigger areas have remained exactly the same). I've done probably 10 normal cleanings, 10 pairs on that channel (running prints through in between), a couple of service mode pairs cleanings and a SuperSonic clean - none of them changed the big areas (the additional little gap may have changed a bit).

Dan

The only thing that comes to mind now is the possibility of air in the "Y" ink line.  I had that with the 9900, in the "O" ink line.  It would probably be more difficult to see it in the "Y" line, but you have to use a light and shine it on the line at quite an oblique angle to actually see it.  If it is there it would appear as a small gap where the Y ink isn't as dense.  The only way that I know of to get rid of the air is to keep running ink through the line.  As you have suggested, a full 8x10 of just yellow would be the most obvious approach, and then just keep running that and see if the air "bubble" is moving at all.  All of this is speculation of course, built on my own experience.  Other than that, follow Marks advice and call Epson.  And by the way, I totally agree with Mark that Windex is NOT a good idea for these print heads.  Also, if you did many of the clean cycles in succession you might have toasted the "Y" channel.  As Mark mentioned a long time ago, it is not a good idea to run many clean cycles without letting the printer "rest" for a while.  I believe that was advice that he got straight from Epson as well.  I hope you'll have some luck with the printer, but I must admit it doesn't look very good at this point.

Gary     

 

[Mark D Segal]

Hi Gary,

Just to confirm - yes, what I have advised on this kind of issue is based on conversations with senior techs in Epson, or their trained contractors. The cleaning procedure should be clean-print-clean-print no more than three such cycles at a time and let the printer rest over night before repeating as necessary.

[Garnick]

Hi Gary,

Just to confirm - yes, what I have advised on this kind of issue is based on conversations with senior techs in Epson, or their trained contractors. The cleaning procedure should be clean-print-clean-print no more than three such cycles at a time and let the printer rest over night before repeating as necessary.

Yes, thanks for confirming that Mark.