Faulty print head on Pro9000 II?

Over the last 2-3 days I've been creating new profiles for my Pro9000 II printer and my photo papers. After profiling I use a test picture to check the accuracy and, yesterday evening, I noticed thin parallel white lines in a blue section of the test print. I ran a nozzle check and saw nothing obviously wrong (see nozzle check 1) but ran a head clean anyway then reprinted the test print, with the same result. I ran another nozzle check (nozzle check 2) and this time, when examining it closely, saw what appears to be some discrepancy in the smoothness at the top and bottom edges of the black, the top edge of the magenta, and the bottom edge of the cyan.

I then cropped out the section of the test print which showed the lines, printed it top left on a piece of A4 paper fed into the printer in portrait mode (the test print was originally printed in landscape format on A4 fed portrait) and the lines were still there, in the same place. I then reprinted the test section but 0.5 cms lower down and alongside the first and still the lines were there and in the same place (white lines.jpg).

The printer has been used a fair bit over the last three days and has performed flawlessly up to now so I don't think this is caused by dried ink on the print head. Nonetheless I am currently in the process of cleaning it (the head's soaking in a mix of Lidl window cleaner and distilled water which has been successful in the past) but I am not optimistic that this will fix the problem.

I have some purged cartridges which I can swap for the others but the fact that there appears to be a problem with three of the colours when running the nozzle check tends to suggest that this isn't a cartridge feed issue.

Any suggestions from the gurus here?

P.S. the 'darkness' of the nozzle checks was enhanced when scanning them in to make them more visible.

You have done a good job in enhancing those nozzle check prints. It may be worth doing a service mode test print, which will show a little more information.

It seems that some Pro9000 II users (including me) have tended to suffer degrading print heads, for no obvious reason. Much cleaning and soaking have proved unsuccessful, but don't let that put you off.

How old is your ink, have you tried a cartridge of OEM ink in the offending channel?

The ink's about 6 months old, from OctoInkjet. I've not used OEM ink since the first set of cartridges became empty but all my cartridges are OEM ones. If the soaking doesn't work I will try squirting some isopropyl alcohol through the head. If this head can't be recovered I shall have to think hard about whether to buy a new head or buy a Pro 100 as a replacement. Right now is when I wish I lived in the US where the Pro 100s can be picked up for a song.

Hi Paul, just looking at your nozzle prints I didn’t think you had a problem at all and found them both to be very acceptable, and pulling the print head out to clean it is not such a good idea either, you should let the printer do that sort of maintenance itself.

If you have printed your test print in two different orientations and the faint white lines are still there in exactly the same place on both prints then it has to be the test print itself that is causing this problem.

Think about it for a moment if the print head was causing this then the white lines would appeared in different directions first horizontally then vertically in different positions on the prints.

Use a different photo for a test print next time and make the two passes again in portrait/landscape direction and then check the results, I would recommend you do a manual head alignment before commencing any further critical testing.

@The Hat
Reading your kind reply it occurred to me your logic was right so I opened the test image and there's nothing wrong with it. It then occurred to me that I was wrong - most of my test images were in A4 landscape but, when I first noticed the fault, I had used A4 cut in half (so A5) and had forgotten I was in fact feeding it in in landscape format so, since I first noticed this, the path of the print head has always been from side to side relative to the sky. When I looked at one or two earlier test prints where the fault was just beginning to show and I hadn't spotted it I found the lines going from top to bottom. So the fault may yet lie with the head unfortunately. :-(

Looking at the lines on the (enlarged?) nozzle check images, they look like marks on the surface that may be caused by the paper drive mechanism. I have noticed such marks on glossy print surfaces when viewed under magnification. You might check with a magnifying glass.

Perform a manual alignment adjustment, use a magnifying glass during inspection of the alignment chart and see if the output is more uniform in the nozzle check. The nozzle checks shows some areas of overlap and maybe that is causing the distortion.

I've now finished cleaning the printhead and, having dried it and reinstalled it, the cyan is worse than before and the photo magenta is also now partially blocked. I don't know why that's happened, I've not had it happen before where cleaning has made things worse. I'm going to leave the head in soak overnight and see if that makes any difference and, if not, I'll probably bite the bullet and use it as an excuse to get the Pro 100.

Hold on a moment, don’t go soaking the head any more, as I said before let the printer do the cleaning, it can do far better than you and it won’t damage the head in the process.

Have you taught for a second that it might be your cartridge that’s causing this print problem and not the print head, just dry the head and put it back in and fit new refilled cartridges then leave it to sit over night, in the morning run a nozzle check.

99% of the time poor print quality is caused by the cartridges so you should concentrate you diagnoses on them and allow the print head to settle down again, what you thing is a clog is in fact caused by poor ink flow from your cartridges.

The initial problem appears to be a print head ALIGNMENT issue to me, not a blocked nozzle. Have you tried an alignment??