Bands most noticeable at bottom of page on Canon ip8500

[Correzpond]

My Canon Pixma ip8500 is printing bands approximately 1.5 cm from the end of each printed page. These occur at the same location on both A4 and 4 x 6 prints.

Example images are posted at http://www.pbase.com/correzpond/printer_problems

Lighter banding in cyan is evident right across the prints, however the most noticeable banding always occurs at the 1.5 cm point.

The issue was originally noticed with Hobbicolors Inks and cartridges, but has persisted through swapping out all the cartridges to Formulabs which makes me suspect a Print-head blockage or perhaps a paper feed issue.

I have cleaned the printhead twice with the 'Windex' method, running both deep cleans and manual printer alignments after each cleaning cycle.

At this point nothing has made any real difference and I am considering purchasing a new print-head from Canon. However at around $AUD200 for a new print head I would like to be as certain as I can be that this is cause of the the problem, and that it is not more likely to be caused by a problem in the paper feed mechanism when the printer is nearing the end of a page.

I would appreciate thoughts & advice from anyone that has seen this type of problem on their Canon and has been able to fix it!

 

[Grandad35]

Correzpond,

I have seen others recommend adding a Post-It note stuck to the rear of the upper right corner of the paper so that the printer feeds the last of the printed area without the normal hesitation at the end of the sheet.

Your problem could also be caused by a partially clogged print head.

 

[Correzpond]

Grandad -

Thankyou. I tried the 'post-it' note fix and the particular end of page banding went away, although the general lighter banding in Cyan across the page remains.

It seems that I may have two issues, one related to paper feed & another related to the printhead, although agree that it is possible that a printhead clog could still be the cause of the end of page banding.

At this point I might try some other methods (e.g. 'Miracle Air Cleaning Method') for cleaning the printhead before I give up.

Some of the more extraordinary cleaning methods posted usually invite my scepticism (e.g. The 'I usually clean my printhead by boiling it in Sulphuric Acid every 6 months and I've never had to replace a printhead yet' type of thing), but I figure in this case I probably haven't got too much to lose.

 

[Grandad35]

Correzpond,

One reason why photo printing is slower than text printing is that the paper is advanced by only a small fraction of the print head width for each pass of the print head so that multiple (light) layers of ink are overlaid onto the same area of the paper (I estimate it to be somewhere in the area of 6-8 overlaid passes on my i9900). The benefit of this approach is that if a single nozzle (or even a small group of nozzles) is clogged, the paper still receives (say) 7/8 of the proper amount of ink and it is very difficult for our eyes to see this slight difference in ink coverage as a band.

This presents a problem at the end of the paper, however, in that the paper rollers are too far back to push the bottom of the paper all the way under the far edge of the print head (both objects cannot occupy the same space at the same time). This problem is solved by stopping the paper near the bottom of the print and laying down the multiple layers of ink using the same nozzles. Obviously, a clogged nozzle will now produce a visible band, since there is no "overlaying" effect from using multiple nozzles. The "Post-It" fools the printer into thinking that there is enough paper to continue overlaying the ink, and it actually provides a paper extension that the paper rollers can grip and push the paper.

In summary, the "Post-It" doesn't actually eliminate the banding - it just randomizes it so that you don't see it. This is why I suggested that you might have a partially clogged print head. Your comment that you still have light cyan banding on the entire print supports this suspicion.

HTH

 

[panos]

Correzpond, do you get a good nozzle check?

 

[Correzpond]

Grandad - Thanks for the intriguing explanation of how printers deal with 'end of paper'. I had always wondered what was occuring when the printer was nearly stationary at the end of a paper; the real complexity of these devices sometimes make it seem more implausible that they work as reliably as they do.

Panos - Yes the nozzle checks, even the extended nozzle checks via service mode, look fine. However I gather from my own experience and that of others here that these checks don't really lay down sufficient ink over a large enough paper area to be helpful except in cases of moderate / marked blockages.

I cleaned the printhead again with hot (near boiling) water last night and saw only a moderate improvement.

Can I ask you both what you preferred methods and fluids are for printhead cleaning, as it seems from this forum it is often a matter of "Ya picks ya method and ya takes ya chances" ?

At this stage I have also just realised that I have 30 days of my warranty left so I am considering returning the unit to Canon while I can.

 

[panos]

Your printhead is fine then. You don't need to clean it.

Are you using third party ink/cartridges ?

I use the windex cleaning method. I have written all my favorite methods for refilling/maintaining at this posting: http://www.nifty-stuff.com/forum/viewtopic.php?id=956

 

[Grandad35]

Correzpond,

Since switching inks and cleaning my cartridges with hot water about 9 months ago, I have never had a clog and never had to run even a single manual cleaning cycle (the standard cleaning cycles after cart changes, etc. are still run automatically). I have changed over 80 cartridges during that time.

 

[Correzpond]

Grandad - What inks are you using? I currently have my printed loaded with Forumlabs replaceable carts, however the problem came up while the printer was loaded with Hobbicolors.

Following from Panos comments I have saved a nozzle check produced from 3 passes through the printer at http://www.pbase.com/correzpond/printer_problems

Most colours show banding artefacts (or perhaps these are aretfacts of the 3 pass process ? I would appreciate your expert comments), however it is the PM which shows a definite blockage.

 

[hpnetserver]

Correspond: Your post have me concerned. I have been using Hobbicolors for about a year with no problems. Just now I pulled my ip8500 out of a pile of computer stuff and hooked it up. Done a nozzle test and printed a photo. Everything is perfect. I have not used the printer for some weeks. It appears no problem still. Thanks god. This printer is expensive. I don't want any problems. Are you sure it was Hobbicolors that caused the problem? Your nozzle test looks like clogs but how it has banding on multiple colors at the same time? I have heard complaints that MIS ink causes clogs (not sure actually). Have you used MIS ink or any other inks on your ip8500? How old is your ip8500? Mine is just out of warranty I think. What is the 3 pass process?