Use QTR to clear clogged nozzles

When I get a clogged nozzle on my 1430, rather than running a cleaning cycle, I use QTR to purge only the channel I want to target.

So if, for example, my K channel is clogged, I use the “PURGE K” QTR profile, and then print a page of large black text. It will start out with some line breaks in the text due to the clogs, but once the ink gets flowing, they usually clear right up. The advantage of this technique is that you are only purging one channel, not wasting ink in every channel, which you would be doing running a QTR calibration page or Epson cleaning cycle.

You can do this with any channel using the attached profiles.

I’ve posted my 1430 profiles here. Just add them to the 1400/1430 folder in QTR and install as usual. It’s very easy to modify these for any printer.

Hope that helps.

I used to do the same thing, until I discovered this: http://www.inkjetmall.com/tech/content.php?166-Flush-individual-channel-using-QTR-Calibration-Mode

Both work. Whatever is easiest.

Brian: I hope you’re still monitoring this thread, you might be just the person who could help me understand that Article you link to. Why does it say this: “This is not the recommended procedure for trying to unclog a printer.” Instead, it links to an Article where the procedure is for ALL the cartridges. Isn’t flushing a technique that can also be used for unclogging? The Article you link to can be used for just one cartridge and that’s what makes more sense to me.

I hope my question is clear… this issue has been perplexing me for quite some time. The Article you link to and Parker’s profiles are more what I’m looking for.

Thank you!

Paul

Paul,

It is not recommended because flushing by printing is not as effective as using suction or extraction to clear a clog. Flushing by printing is designed to use a cleaning fluid to clear out an ink channel. Also, we believe the best practice is to not over-stimulate a nozzle when it is clogged because doing so is a risk to permanently burning out a nozzle.

If an ink channel is clogged, or there are one more nozzles that are clogged, or there is a clog behind the nozzles and normal printing does not clear it - then printing PiezoFlush may be similarly non-effective. Having said that - there are people who have used PiezoFlush to print through problems.

Using suction or injection to pull or push PiezoFlush is done with great force in comparison to the tiny pressure produced by stimulating the print head nozzle to expel tiny ink droplets. If the nozzle can not expel ink by printing, it may not be able to expel the ink that is in front of the PiezoFlush in order to get the PiezoFlush to the clogged nozzle.

So it is a matter of physics as to why we make that recommendation. Using the small format cleaning kit should not be done with “great pressure”. I am only saying that the physics of using pressure by INIT FILL or injection is so much greater than the force generated by printing.

Hope that clears up our best practices recommendation for clearing clogs versus flushing out an ink channel to change ink types.

The only thing I’d add, since I was asked, is that not every nozzle gap is a clog, especially on a desktop. If successive nozzle checks always show the gaps in the same place then there’s a reasonable chance that it is. However if the gaps move around, then my view is that it probably isn’t, rather it’s probably air in the system. In such circumstances my experience is that head cleans tend to make matters worse, and I get better experience from a combination of purge patterns and patience. I only have limited experience with printers with ink lines and dampers, but on desktops using refillables this phenomenon is fairly common. Some discernment is need to know whether or not you have a clog.

Thanks, Jon. So, if I understand you correctly, flushing by printing is more stimulating to the nozzle than suction or extraction? That surprises me… I would have thought the opposite because “Using suction or injection to pull or push PiezoFlush is done with great force…” Sorry, something very basic I’m not getting my head around on!

And Brian… yes discernment re clog or air is key. I would guess that discernment comes mainly with experience. I have a pattern which might be a little of both… is that possible?

Regards,

Paul

the problem with stimulating a nozzle’s piezo crystal is that if there is no ink in it - it causes overheating that can even begin to affect adjacent nozzles.

so its the stimulus we want to avoid if there is a clog. doing powerful paired cleanings repeatedly on a 9900 head which does not have ink in some of the nozzles just kills it quickly.

sucking ink out of a print head is just that. no electrical stimulus and it can not overheat - and the pump does not use more force than is safe. and its really effective when using a solubizing cleaning fluid if agglomerated pigment is present in the system. the only downside is wasting ink in channels that do not need flushing. but the cost of ink in comparison to ruining a print head is small price to pay.

pushing flush through the head can be done with way too much force and that should be done gently…if injecting…

Thanks, Jon… now I get it. How can tell if I’ve fried some nozzles?

Here’s another basic question: For any given cartridge there’s a pattern of 9 sloping lines, each line consisting of 10 “steps”. Is each step a nozzle? or is a whole “stairway” of 9 steps a nozzle? I suspect the answer is each “step” is a nozzle.

And… is Piezoflush a solubizing cleaning fluid? I just bought a 350ml bottle.

Regards,

Paul

each line is a nozzle sending out a bunch of droplets to form a line. So each line is supposed to stair step.

If it stays on the same level as the one before it or after it - that indicates it is misfiring in the wrong location usually due to some lint or other material under the print head - but sometimes electronic.

If it is not present at all then the nozzle is not firing at all due to air or a clog. If it is always not firing this usually indicates a clog. If it bounces from one location to another this usually indicates some micro gas bubbles in the system. If a swath of them are not firing this can be due to a dirty wiper blade or capping station that is leaving residue in the same place under the head each time the print head is cleaned - or may indicate a bunch of adjacent nozzles that have been affected. That is why we caution against producing heat with repeated cleaning or printing of a nozzle that does not have ink in it.

PiezoFlush is designed to resolubize agglomerated pigment - and has several wetting agents that are powerful and not found in normal inks. So, it is most definitely not a “clear ink base”. Getting it in there and allowing it to sit can clear stubborn clogs - but can not unfry nozzles. And it is proven to be safe in printers for long term storage.

We believe that if the PiezoFlush can not clear freshly clogged nozzles then the nozzles may be fried. So, if a clog develops and PiezoFlush is used it has the best chance of recovery. We have saved a lot of printers for our customers and we have recovered a lot of printers dropped at our door as being dead. We have bought our fair share of used printers with bad channels and fully recovered them. But we have also encountered swaths of missing nozzles that there is nothing we can do to recover including removing the head and using the injection method. We can see the PiezoFlush coming out of these nozzles - but when installed no ink exits them. They are electronically dead. The nozzles can not be stimulated to expel droplets.

Anything is possible.