L1800 alignment problem

I have an Epson L1800, fitted to a Chinese flatbed; printing ecosolvent ink onto plastic items. Normally very well! However, when I go to align the printheads the alignment immediately goes WAY out of alignment and cannot be restored. Have printed hundreds of alignment pages. Cannot get good alignment. Even tried printing all 1s, all 9s, and even 'reverse' - when closest is say # 3 of 9, then you input #7! Blv it or not, sometimes this has given the best success!

But still not acceptable.

In the past only a new printhead or mainboard fixed the problem! ;-(

How can I fix this? Could my printer / driver have been corrupted?

Grateful for any advice!

I don't have an idea whether the ink could have an impact onto the alignment or could it be a varying distance between the nozzle plate and the objects you are printing on ? Did you try to disable the bidirectional printing in the driver ? That's the fast/quick printing option in the settings of Epson drivers.

Thanks, ISF. I don't think ink has much to do with it.

What my print looks like - but the amount of offsett in the print varies a lot with each run of the alignment programme.




On the Mac, there are only 3 lines in the alignment programme. These two sheets show 4 runs of the L1800 alignment. As you can see, the first line is 'ok', second line not, and the 3 lines (at the bottom) so out of focus its hard to check which square is correct. Have done this 50 - 100 times in the last few weeks, no improvement.




This test is from the Windows alignment test. Run this many times as well, but the answer is always ‘6’ ?? Never changes - ???




Would be very grateful for any insights!! I have had this problem for years, - usually I have to throw out printhead, or mainboard, or both, or printer!!!!


Thanks,

Stuart.

@Stuart21, when uploading any test prints for scrutiny, it would help so much if you didn’t have anything printed on the reverse side, it would also make it so much easier to give a more definitive answer...

- please follow @The Hat 's advice to show clean prints - scanned or as a clear close up photo of a text or other image print showing the actual effect of the alignment problem

- your 1234.png shows some washed out/unsharp scan or photo ? of some small print, it is visible at the word 'Bangkok' that there is an alignment problem. Please to a test to print a word both with and without the 'High Speed' option activated on the extended driver tab, this controls the bidirectional print, and post such prints for comparison

- I think there is a misunderstanding how the alignment utility works

Stuart21 said:

Run this many times as well, but the answer is always ‘6’ ?? Never changes - ???

Click to expand...

Yes, not wonder, every time you start the alignment program it starts with the same default values, again and again, you won't see the changes in the print you expect after entering some correction values, you would need some other test print before and after you go through the alignment steps. Again - if you start the alignment utility it won't use your previous settings.
There is one option in the software that you can directly redo step 1 from within the program , you enter the correction values and directly repeat that step and if you then enter some other values you are done with that step.
(I only can comment to the Windows version of the alignment utility)

Thanks. Here we are - as can be seen the alignment, particularly for 'out of focus' line 3, is almost random -

Ink stained Fingers said:

- please follow @The Hat 's advice to show clean prints - scanned or as a clear close up photo of a text or other image print showing the actual effect of the alignment problem

- your 1234.png shows some washed out/unsharp scan or photo ? of some small print, it is visible at the word 'Bangkok' that there is an alignment problem. Please to a test to print a word both with and without the 'High Speed' option activated on the extended driver tab, this controls the bidirectional print, and post such prints for comparison

- I think there is a misunderstanding how the alignment utility works

Yes, not wonder, every time you start the alignment program it starts with the same default values, again and again, you won't see the changes in the print you expect after entering some correction values, you would need some other test print before and after you go through the alignment steps. Again - if you start the alignment utility it won't use your previous settings.
There is one option in the software that you can directly redo step 1 from within the program , you enter the correction values and directly repeat that step and if you then enter some other values you are done with that step.
(I only can comment to the Windows version of the alignment utility)

Click to expand...

.....................
On a Mac Os, if a high q square is shown, you click 'finish'; if there are still lines, you select 'realignment' and the next process is to print again, 'hopefully!!" corrected!? Hope I am wrong and shown a better way!

I can only print 'quality' setting - other settings produce gaps etc -

What would cause the 'out of focus' print of line 3?

TIA!

Stuart21 said:

What would cause the 'out of focus' print of line 3?

Click to expand...

The only thing that I know that would cause a line skip to get skewed is the line feed timing strip, its located on the left side of the printer, cleaning may rectifying the problem, it may not work either but it’s worth a try...

o.k., the images are cleaner but don't really show whether and what type of problems you have in actual printouts.
This is the advanced/extended driver settings tab of my L800 , not L1800 , Windows driver which shows some printing options in the middle including a 'High speed' option, this turns on/off the bidirectional print.


Alignment problems may show up in actual prints different ways, one typical effect are
shadows on letters which is a tpyical horizontal timing issue, or you may see gaps and banding in the width of the height of a nozzle row, that vertical banding would need find tuning of the
paper transport. So the question is which type of mis-printing due to bad alignment do you see
in your actual printouts whatever that is - text or line patterns, graphics or images ...
And there is another reason which can cause unwanted effects, that can be a dirty timing strip or some dust on the coding wheel for the paper transport. The timing strip is the gray band which passes through a sensor on the back side of the printhead carriage, you can clean it, with some window cleaner and a piece of kitchen paper. The coding wheel is not directyl accessible wihtout taking the top cover off.
So please show us an actual print sample with whatever text, graphics or image with an alignment problem - after you have cleaned the timing strip and passed the alignment utility once.