Canon nozzle test pattern - help in interpreting

[martin]

I've run both the nozzle test print and the Service test pattern on my Canon i455. I've just fitted a new print head and have fitted new cartridges.

There's a problem on the test patterns:

On the Service test print, there's a cyan band 1cm high a third of the way down the page with a long needle-shaped white patch some 7 cms long extending in from the left edge and a similar larger needle-shaped white patch extending in from the right edge some 15 cms long lower down in the cyan band.

On the nozzle test patterns generated from the Maintenance tab in Printer Properties (Control Panel) I also get needle-shaped white patches showing extending in from the right-hand edge perhaps a milimetre wide and up to a couple of cms long.

I've done the print head alignment and deep cleaning and the needle-shaped patches remain.

I'd be very grateful if someone can tell what such patterns ore indicative of.

Thanks

Martin

 

[Smile]

Images, scans of your prints would help alot. It could be that you get feed problems, air in the system (but deep cleaning would fix this). Also if the problem is constant there can be electrical problem.

 

[martin]

Many thanks. Picking up on your comments on air in the system, I have just did a further search on this forum. The second and third pictures in the thread:

http://www.nifty-stuff.com/forum/viewtopic.php?id=2982

show a perfect example of the sort of thing I'm finding in the top colour (the black nozzle pattern) i.e. the needle-shaped area extending in from the right-hand edge.

I think you are onto something when you suggest air in the system. If it is a sealing problem I assume the problem area is the joint the colour cartridge makes around the 3 interfaces with printhead? Perhaps I could test this by smearing some ink or water around each exit hole on the cartridge to create a liquid seal at the interface?

Any further advice or suggestions would be much appreciated.

If you still think pictures of the snag would be of use, I can sort that out tomorrow.

Martin

 

[Smile]

As stated in the thread you gave me link to:

"an ink flow problem rather than a normal printhead problem"
"I believe it is a problem in the cartridge"

The solution would be to "verify this by replacing the cartridge with a new one or just a different one"

If that does not solve the problem then you can try to clean print head with some recipe you can find on this forum. Please write how this turns out. If you need further help with cleaning I can give you my instructions.

 

[dan_uk_1984]

The shape you are describing usually means the cart is TOO full, and is leaking slightly.

Usually the head shoots the ink out of the jet and onto the page, when there is too much ink the ink "wells" on the surface of the head. The droplet of ink is thicker in the middle so no ink makes it to the paper. At the edges there is either a very thin layer of surface ink or none to impede the normal use.

You can verify this by taking the cart out, getting some kitchen towel and twist it up and put it on the offending colour and "wick" some of the ink out, about 15 seconds should do (otherwise you will empty the cart)

I figured this out when refilling BCi-24's for a cartridge refilling company.

ps, the reason why a deep clean sometimes clears this up is that a deep clean uses so much ink it can solve the prob as same as the kitchen towel - but obviously it does it to all colours.

 

[martin]

Many thanks to both Smile and Dan.

That the cartridge is too full does make sense; I can see that the cartridge pads are wetter than those of a new OEM cartridge. (A few months ago, worried I might be over-filling the BCI-24 carts, I asked, on the refilling forum, how to gauge when it's properly full and prevent over-filling. ) I will wick out some ink with a paper towel and report back with the results together with any thoughts on how to assess when the cartridge is optimally full.

I'm very grateful for the suggestions and advice.

Martin

 

[dan_uk_1984]

To refill a BCi-24......

1. Pop the cap off (a strong blade under the edge and a twist will pop it off) {For the black I just drill a small hole in the existing air hole}
2. Fold 2 pices of kitchen towel up into a square about 2"x2"
3. Hold the cartridge upright on the tissue holding it down firmly
4. Insert needle 1/4 inch through the air holes at the top (make them wider with a VERY small drill bit if your needle is too wide)
5. Inject ink SLOWLY untill you see ink spread out on the kitchen towel, then suck out 1ml
6. Glue or tape the lid back on. (hot melt glue is good because it is easy to remove in the future, if you dont care how it looks just put some tape over the lid)


Doing the above on tissue tells you when the colour is full, and also stops the colours running together. Sucking out 1ml means you should avoid the problems you've been having. Generally you will only get 3 good refills out of a 24, the more you fill it, the less ink it will take. But the OEMs arent massivley expensive and the i series of printers that take the 24's like good quality ink or if your going to give them refills an oem every 5 refils is a good idea....

Hope this is of some help.

Dan

 

[martin]

I can now confirm that the problem - needle-shaped white patches in the noozle test pattern - was caused by an overfull cartridge.

Yes, I have noticed that an OEM cartridge is good only for a couple of refills. In fact, I took apart a new cartridge and saw that the absorbent 'sponge' was not at all absorbent and also had a significant portions that had failed to carry any colour. A few months ago I refilled both black and colour BCI-24 carts with absorbent strip material that one can buy here (UK) for soaking up condensation from interior windows etc. Also, after a couple of refills, I've tended to flush these through with distilled water and then spun out the residual water out using the fast spin on a washing machine before refilling with ink. What I will now do is deliberately underfill i.e. fill with no more than 3ml, thereby avoiding the overfill problems, which I've found can easily lead to even further problems through blockages and subsequent cleaning.

I've also been using the JR Inket flush to clear blockages and a mistake I made was to fill a cleaning cartridge with this stuff and, after deep cleaning, do a nozzle check. It seems that if this flush is fired through the nozzles, unless it's free from dissolved ink, it can cause blockages. It appears it should only be used with the head out of the printer following which, the head should then be well flushed with warm water. Similarly, I've found - the hard way - that if this flush is used to clean a cartridge, the cartridge must be well flushed afterwards with water to get rid of any vestiges fo the flusjing fluid I assume that it evaporates inside the nozzle rather than being ejected onto the paper, which might be ok if it's pure, but if there's any dissolved ink in it, that ink appears all too easily to block the nozzles. However, I'm sure that more experienced contributors that I have previously found this out.

Many thanks for pointing me in the right direction; I'd been barking up the wrong tree until you made me aware that overfilling was the problem.

Martin

 

[Smile]

Strange that you seem to have problems with refilling OEM cartridges.

OEM is the best cartridges to refill. Why did you change sponges inside OEM cartridges? You only needed to purge them, see granddad method here: http://www.nifty-stuff.com/forum/viewtopic.php?id=311 and here:
http://www.nifty-stuff.com/forum/viewtopic.php?id=2663

Other than that it's best to refill with high quality ink (no contaminants) and to fill using vacuum. Then optimal ink saturation is very easy. No under or over filling. And purging is required only on very rare occasion.

 

[Trigger 37]

martin,... before we close this subject, you didn't really explain how you came to conclusion that "Overfilling" was the problem. The BCI-24 Canon ink cart is not like any other Canon ink cart used in the newer printer. It is a carry over from the printers that Canon put out in the mid 1990's. For example, I owned a Canon Multipass 2500 which uses either a BC-20 or the BCI-24 printhead with a Blk ink cart and a tri-color ink cart. These are sponge based ink carts that have no ink reservoir.

This type of ink cart, like those of HP, Lexmark, etc. have always had a problem with "Trapped Air Bubbles" preventing ink from flowing out of the ink cart. So when you agree that your problem was over filling, please explain, what you did to correct the problem in detail. To my limited knowledge, "Overfilling" implies that since the ink was all the way to the top, no air could get into the ink cart since the air intake was blocked. This would cause the "Ink Starvation" printing you have described. However, just removing 05.ml of ink would resolve this problem. As you indicate, these type of ink carts won't take many refills, partly because of the air that get trapped in the sponge and becuase the old type sponge traps old ink the flow of ink is block internally. Prints then look like the ink is starved,... and it is. Starve a printhead and continue to "Fire" it by printing will burn it out. Just printing a nozzle check should not burn it out. This typically uses such a small amount of ink the ink cart can usually supply sufficient. Try and print a whole page and you will see starvation.

On Canon's newer printers, the Engineers changed the Nozzle check pattern to one that prints long solid bars rather than one that prints a nozzle matrix. The reason for this was the starvation problem, since the old pattern would not show a starving ink cart very well and the new bars tent to show it in detail as demonstrated by the pictures in the link you provided. The rational is that the Service Test Pattern still demonstrated the details of each nozzle, and the basic nozzle check provided more information for the owner.

Give us some more detail on exactly what you did and what the first test results were that convinced you the problem was solved.