Frustrating Head Clog!

[Charles218]

Thanks for the suggestion, however it did not make a noticeable difference. The top nozzle print was after printing 10 test patterns, I then proceeded to do a Epson cleaning, the bottom nozzle print was after the cleaning. Before the cleaning, the orange and PK and quite are bad, after the cleaning they are worse.

 

[The Hat]

The top nozzle print was after printing 10 test patterns, I then proceeded to do a Epson cleaning,

No, what I wrote was, do some test prints, (real prints, images or photos), not patterns, you need to get the print head working again and allow some ink to pass through the heads.. Don’t do any cleaning..

 

[Charles218]

Thanks for your patience with my inexperience, here is where I am. I just completed 10 full color 8.5 x 11 prints, the top nozzle check is where I was before the first print. The middle nozzle check was after 5 prints, followed by the final one after 10 prints. Before I initiated the 10 prints I checked each cartridge for prime and ink level, and discovered that Orange had lost it's prime. I re-primed it and topped off the ink. The Yellow cart was low on ink, it appeared to still be primed though I'm not 100% sure, I topped it up also. As can be seen, the yellow is barely printing and the orange is not printing at all. When I started several days ago, it was just the PK that was giving me problems, these last two nozzle prints show almost identical PK bars.

Is there anything left to do that I have not tried? Should I try the PiezoFlush on the yellow and orange?

 

[Ink stained Fingers]

I'm getting irritated that orange and yellow are dropping out very much as well, what type of cartridge are you using - refill ? or 3rd party ? Can you try another fresh set of cartridge at least for the affected colors ?

 

[PhilE]

I came across this article explaining clogging on Epson printers that was informative:


Mark McCormick
http://www.aardenburg-imaging.com
Clogs in Epsons. So totally misunderstood. Most clogs on Epsons are the result of the breakdown of the meniscus at the exit of the nozzle.

These are not clogs but the disappearance of ink from the nozzle chamber leading to the printhead not being able to pump the ink out. Ink is literally non compressible but air is. So once air has infiltrated an Epson nozzle, it unable to pump ink out. Once you figure this out and why it happens then you will have found the answer to why Epson typically need to use more ink to clear the air out of the passageways and ink chamber. It literally needs to "flush" out the chambers.

The long cycle of cleaning by Epson in the last 10 years or so was because Epson discovered that having a fast strong vacuuming of the printhead in a cleaning cycle was not good. The reason is that the strong vacuum actually made the bubbles in the chamber expand sometimes would break up inside the chambers and foam up the internals making a good nozzle check more difficult.

The solution was to use an extended SLOW and gentle cleaning cycle, This was more effective in most situations. Even Canon also arrived at that conclusion as well. So many users will hear this long drawn out cycle and conclude,,,,,it’s taking all the ink out.

The breakdown of the meniscus is a natural random event when ink detaches from the nozzle. When you see an Epson AMC printhead. It stands for Advanced Meniscus Control. Here the meniscus naturally bounces around the nozzle after the ink droplet is detached. If you allow it to do that, at certain cycles when you try firing the piezo nozzle again it can help fire or it will not fire as efficiently because it is bouncing around. The Advanced aspect is when Epson used antimodal frequencies to quick settle the bouncing of the meniscus between each firing. AMC printheads are not found on the lower end Epson desktop printers. The lowest one it trickled down to was the R3000.

Now you know a little bit more, then you will start to understand why a maintenance tank is necessary on Epson printers.

Clogs do occur but they are far less frequent than air entering from underneath the printhead via the nozzle.

 

[Charles218]

Finally some improvement! I found a YouTube video here, it has you using a syringe to push air through the cartridge breather hole. I tried it and for the first time all colors printed including about half of the bars on the troublesome PK cart. Yellow and Orange are now back to printing without any problems. I have attached yet another set of nozzle tests, the top one was right after pushing air through the yellow and PK carts, as you can see this yielded by far the best test to date. I then ran a cleaning hoping to get the remaining bars to print on yellow and PK, but you can see in the second test that the PK has almost disappeared. The bottom nozzle test was after just letting the printer sit for several hours, no pushing air through the cart or cleaning.


So the question is, why after getting a pretty good nozzle check pattern in the first print do I lose most of the PK after a cleaning cycle? I will try one more time pushing air through the PK cart, but I am a little concerned about damaging the print head.


Mark, thanks for jumping in with info about ink not being available at the nozzle chamber. Do you know if the article that you are quoting from also applies to my small desktop style printer, or is it only about the large format printers? From what I understand, which isn't much, my printer does not have a maintenance tank. Do you happen to have a link to the article?

 

[Ink stained Fingers]

thanks for your feedback that you could solve your nozzle problems, I'm not clear at this point yet why yellow and photoblack PK were affected, and not the other colors

The actual physical situation in the nozzle and at the exit is pretty complex, if you want to read more about resonances and ozciallations you may read it here at pp 96 - 99 , and more about wetting on the following pages, and chapter 6 about air entrapment

https://ris.utwente.nl/ws/portalfiles/portal/6085963/thesis_Wijshoff.pdf

 

[PhilE]

For Epson printers, it is important to periodically clean the inside of printer as described in link. The capping of printhead needs to have a good seal to have the vacuum to pull air through in the cleaning cycle so cleaning around seal is necessary periodically. High end Canon printers have a much more elaborate automatic cleaning cycle that Epsons do not have.

 

[Charles218]

Success at last! After more than a week, I was finally able to get my P400 printing again, mostly with the help from those who chimed in on this thread and a couple of YouTube videos. The attached nozzle checks are the two most recent. I think the turning point was the technique of gently pushing the ink through the cart using the breather port. Thanks Everyone!!!

 

[Ink stained Fingers]

the technique of gently pushing the ink through the cart using the breather port.

That's an option to be used with care - the problem can be with the cartridge - with the gromet at the ink outlet -
it has to be tight or you otherwise push some ink out at this point and flood the bottom of the printhead carriage with ink which may propagate to the flat cable connector causing further damage/short cuts there. I have seen that on another printer than the P400. So yes - if you carefully watch for it it is a possible way to clean the nozzles.