Nozzle check print - blue band is split into 2?

[OM2]

I've purchased some inkjet solution from eBay
(This being after having a fruitless search looking for Windex equivalents)
I've cleaned the head - the solution looks pretty good - one or two drops and you see the ink dissolve away!

I've done a nozzle print check and this is what I get:

There still seems to be a problem - other prints have been both better and worse

The thing that has me really confused is: why is the blue band split into 2??
Doesn't make sense to me
Any thoughts?

ALSO, I got another blue ink cart from my MX870 and tried that
This gave a better result:

The same problem with the blue exists - it's still split in 2
BUT the print is much much clearer - why???

Thanks in advance


Omar

 

[PeterBJ]

The fact that the cyan band is split in two exactly at the middle horizontally means that the printhead has an electrical defect. Only a new printhead will help. No amount of cleaning will help curing this problem. Clogged nozzles would show a more random distribution.

I think the second nozzle check shows better cyan because the second cyan cartridge is better than the first with no ink flow problems.

An extended nozzle check will show the defects in more detail. For this you will need the service manual for the MP640, which is here: http://www.bendata.de/Downloads/Canon/mp640_e.pdf see section 4-2 Service mode operations on page 39/54 and on.

You will also need a Canon service tool like v.2000: https://rapidshare.com/#!download|927p6|1749656189|ServiceTool_V2000.exe|401|0|0 This service tool works with windows XP, Vista and 7, but only with 32 bit versions of the OS's

As far as I can see from the service manual, the procedure is the same for entering service mode on the MP640 and the smaller MP540 I used for test and writing the instruction: http://www.nifty-stuff.com/forum/viewtopic.php?pid=51824#p51824

 

[OM2]

@peterbj, thanks for the reply
i missed one step that came with the instructions for the cleaning solution
it said you should clean the bottom of the print head by soaking in 4mm of the solution
i've done this. problem now solved

i'll keep the other links given for reference - thanks for that

 

[OM2]

hmmm... all may not be well as i assumed
i did a print of blue colour
something weird happens
fast: print ok
standard: has gaps in - shows there's something wrong
high: looks rubbish! has different shades of blue

see below for the prints scanned

fast:

standard:

high:

should i further diagnose?

i have to do a certain print everyday that involves printing a block of blue that is 1cm x 2cm
this has to be printed maybe 3 or 4 times. it doesn't have to be perfect
just wondering if i continue to print, will my print head be further damaged if it's not fixed properly?

thanks

 

[PeterBJ]

I think the blue rectangles look like there is an inkflow problem, especially the one made with standard printing. Try cropping the images to show only the blue rectangles. This will give more detail due to less compression, as there is an 80 kB limit to file size for uploaded images.

I think the pattern is similar to this: http://www.nifty-stuff.com/forum/viewtopic.php?id=7744 , that was caused by a blockage in the magenta cartridge.

A simple test that can determine if the problem is caused by the printhead or the cyan cartridge, is to buy one new OEM cyan cartridge. If the printer is OK with the new cartridge, you know that your cyan cartridge is at fault and possibly needs flushing. If the new cartridge makes no difference, you know that the printhead is at fault and possible needs more cleaning.

An inkflow problem will normally give a varying pattern, clogged nozzles will normally give a regular, not varying striped pattern.

Don't give up. It looks as your printer is almost OK again. I was certain that the printhead was ruined, but it looks like I was wrong, which in this case was a good thing

 

[OM2]

@peterbj, thanks for the reply
i think the ink cart is the problem
before, i tried a perfectly working one from my mx870 - that gave a solid streak of print when doing a test

question: how do u flush an ink cart?
the thread u gave a link to has tooo much info

@the_hat said in the thread: "I purged each cartridge with tap water till clean and then added one ml of alcohol to each then blow out the excess water and dried them both using ghwellsjr tissue method on the outlet."
where is this famous method?
thanks

 

[The Hat]

@the_hat said in the thread: "I purged each cartridge with tap water till clean and then added one ml of alcohol to each then blow out the excess water and dried them both using ghwellsjr tissue method on the outlet."
where is this famous method?
thanks

When you need to find a past post on Nifty just do a little bit of digging using the search button and your time and patience will be rewarded..
http://www.nifty-stuff.com/forum/viewtopic.php?pid=34175#p34175

 

[Tudor]

question: how do u flush an ink cart?

Here is a video that helped me:
http://www.youtube.com/watch?v=QqnZU1u45aQ

And this is how I do it:
1. fill the cartridge with window cleaner and leave it for 30 minutes
2. flush it with a solution of demineralized water+window cleaner (see the video)
3. finish with pure demineralized water
4. apply ghwellsjr's draining method