L800 - pigment inks - contamination?

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Got a bit of an annoying issue with an L800 we're playing with...

We've been documenting the various processes and things that can go horribly wrong but despite expecting issues like clogging, etc... we found ourselves faced with a whole other issue.

The Magenta channel is getting polluted with Cyan between each print.

I've ruled out:

• CIS reservoir pressure
  (just lifted the printer up so all ink levels below printer).
• Clogging
  (all nozzles are firing)
• Contamination at reservoir
  (Yes I checked)

I have a horrible feeling that the issue is within the printhead and the issue is a badly manufactured printhead with the Cyan leaking into the Magenta channel as they're located next to each other.


I should note we haven't done anything such as manual printhead cleaning, or disassembly of the buffer assembly on this thing but it's looking likely we've a £300 waste of space... :/

Any other suggestions I might have missed?

 

[Ink stained Fingers]

I'm running an L800 but did not observe that effect so far, I'm using the Fujifilm DL dye inks, not pigment inks. But I would raise some questions to locate the problem:

- is that effect getting better or worse when printing some color pages ? Is it more prominent after
a resting period ?

- Did you start the installation directly with pigment inks, or with the genuine Epson inks first ?

- Is the effect visible in the nozzle check print - is is always at the same nozzles ? Is there something
on the cleaning unit around these nozzles ?

- If you change back to dye inks - what would happen ? If that effect continues with the original dye inks it would constitute a reason to claim warranty. I guess that might not be so easy if the unit was not procured via a national dealer.

 

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- is that effect getting better or worse when printing some color pages ? Is it more prominent after a resting period ?

The effect tapers off as the page progresses but re-appears almost immediately (ie: within 5 seconds) when the next page starts.

This indicates the issue is caused primarily when the printhead is static (although not necessarily waiting in the resting position) which normally would give me a reason to think it was a blob of ink on the underside of the printhead.

- Did you start the installation directly with pigment inks, or with the genuine Epson inks first ?

OEM first... we installed and ran numerous tests on the it with OEM but having looked back through the output we didn't print in anything other than High Quality Photo which makes the issue very difficult to see. I suspect it was already evident to a degree though.

Is the effect visible in the nozzle check print - is is always at the same nozzles ? Is there something
on the cleaning unit around these nozzles ?

Yes and no. It's clearly evident in the centre area of the nozzle check. Some nozzles are more affected than others with the outer fringe/circle of nozzles unaffected.

If you change back to dye inks - what would happen ? If that effect continues with the original dye inks it would constitute a reason to claim warranty. I guess that might not be so easy if the unit was not procured via a national dealer.

Will be finding that out Monday when we're disconnecting the dip reservoirs we put on with the pigment and attach some compatible stuff first.

I've got another 8 of these units so we may have to requisition another one to see if this was a one off or not.

 

[websnail]

Just to follow that lot up as I was interrupted by the grand familia for a bit there..

The blobbing possibility is something I tested for by running the printhead over some kitchen towel and no there's no obvious cyan deposits there.

Like I said I'm suspecting it'll be the printhead or the feeder system is fubar. Sending it back is a no go though, given what we've done to the unit

 

[martin0reg]

My experience with cross contamination on a r285 (=L800 without "ITS" ciss) was mostly due to

- the purge pad not working properly, so that the print head is parking in an ink puddle
- wrong pressure from refillable carts, i.e. different pressures, one or two in the set with too little or too much ink flow. Oftenly combined with ink blots while printing..

I know, you have no carts ... but apparently you have replaced the "ITS" ciss with a special one..

..
Will be finding that out Monday when we're disconnecting the dip reservoirs we put on with the pigment and attach some compatible stuff first.
...

.. so could it be a similar issue of wrong pressure from the ink source, not from bad carts - but from your tubing design?
Just a thought..
..if it's not the head...
Or the dampers which are gone empty or unbalanced filled for unknown reason!?
This would mean you have to prime the dampers. But I don't know how you can see the filling of the dampers, or how much you will have remove to get access to the dampers...

 

[websnail]

Yeah I wondered about that too but I now have the printer elevated with the reservoirs literally below the level of the printer so if anything they should be drawing ink backwards.

Likewise the blog/puddle thing is moot as there's literally nothing there and the problem recurs even without the printhead touching the capping station/cleaning-pad.

It's an odd one but keep the idea coming... Might be something in this yet.

 

[martin0reg]

You were faster with posting.. I just have add to my previous post: the possible issue with the dampers, see above..

 

[mikling]

Keep room temperature steady.
Perform a nozzke check. With photo paper.
Let printer rest for at least two hours.
Perform a nozzle check again. If there is crossbleed in the pattern.

The ideal is to use carts to test.

Then you have printhead delamination. This is something that very old Epson hardly had. Now it is a common failure mode after a few years. The printhead is built up layer at a time, like a 3d printer somewhat does. If the barrier between colors let go, this will happen.

On the very first generations of Claria machines the most common spot was yellow black, most 1400s and 1430s die this way. Head delamination.

 

[Ink stained Fingers]

I assume the L800 is a pretty new one, out of the box - or already running for a while ? I'm wondering what Epson has done to the printheads since the R265 and similar starting with the Claria inks, I have used up a few printers, but never with this type of failure. If there is a connection between the ink channels in the printhead it should work both directions. Contamination in a darker color with a lighter color may not be visible, but when you swap the two colors assumed to be affected it should become visible. Or you fill cleaner instead of inks into the reservoirs - into all but one to test the effect.

 

[websnail]

You were faster with posting.. I just have add to my previous post: the possible issue with the dampers, see above..

We've not pulled the damper block out as yet but it's on the list of things to document anyway so we'll see.

One thing that did occur to me was the possibility of a pierced/leaky film in the buffer. Given the design of the reservoirs and some printhead tubing blocks that's not entirely unlikely...

Thanks for the suggestion...