Wonky printing on Canon MP780

[kdawes01]

I have a Cannon MP780 that is giving me fits! When it is printing text, it skews the lettering. i.e. an I can look more like an I - could be skewed to the left or right. Might even just "bend" a letter in the middle! If what I am printing has long vertical lines and I force the printer to print in Greyscale, the vertical lines periodically offset so that a line looks like this
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Not as much offset as above but by about 1/64 of an inch or so. Enough so that the line looks to step back and forth. I'm assuming that it depends on which way the printhead is traveling.

If I switch to to the photo paper setting, so that it uses those inks instead of the text ink, it prints things just fine.

Any clue what is happening? Do I need a new printhead? Take it apart and clean and oil it? Get a new printer?

Hope someone has a clue!

Thanks!
Ken

 

[embguy]

Have you try print head alignment?

My 6 years old Canon i550 sometime does that on draft mode because it uses bi-directional printing. I think the normal mode print only in one direction. Does it do the same when printing in normal mode?

 

[kdawes01]

Hi embguy,
Yes, I have gone through the printhead alignment... doesn't help the problem... Draft mode is even worse...
Ken

 

[Grandad35]

Any clue what is happening? Do I need a new printhead? Take it apart and clean and oil it? Get a new printer?

Look at this thread. Note the fix in post #26 on page 3.

 

[Manuchau]

I've seen that happen before. The clue is that it only happens in th plain paper mode. It seems to be either a problematic bci-3 black cartridge, or the bci-3 blk hole in the printhead needs a flush....

 

[panos]

I have a Cannon MP780 that is giving me fits! When it is printing text, it skews the lettering.

I did have this problem as well and it went away when I switched to auto head alignment instead of manual. Auto head alignment seems to be taking more factors into account, for example it rolls the paper forwards and backwards many times. Try it.

 

[Trigger 37]

kdaweso1,... Most of the time this problem is caused by ink splatter getting on the timing strip that runs the width of the printer and passes through the back of the Carriage/printhead ASM. If any ink gets on that timing strip it can give false locations in both the left to right and right to left printing cycle. This will "Skew" the print characters. Open the cover and use a bright flashlight. Pull the power cord and move the Carriage ASM to one side and examine the timing strip. The move it to the other side and do a 2nd exam. You have to be EXTREMELY CAREFUL in cleaning it with a tissue and Isopropyl Alcohol, as if you strech it one way or the other you may disconnect it from one end. If you do that you will probably have to take the printer apart to re-connect it. Also look close for greese smears on the timing film strip. These are just as bad as ink spots.

 

[kdawes01]

I'd like to thank everyone for their input...
I now have a pretty clean machine! I tried cleaning the timing strip, manual and auto head alignment, cleaning/flushing the printhead, new cartridge, etc., etc....
Know what worked?
A new printhead... Popped that sucker in and VIOLA! The problem went away! I don't know the mechanism of failure... Just that a new printhead fixed it!

Once again thank you to you all!

Ken