Ink Appears To "Fade In" After Short Time

[porl]

I'm not sure how better to describe this, but I am running a new "Generic Chinese" printer using i3200 print heads. Everything seems to be working okay (or at least has a workaround) except for one major issue. Any time a colour channel is not used for a short time (even within one print image) it appears as though there is a blockage. After a small delay it is back to normal again. Basically, the start of any image, or the start of that colour in a region of the image, it looks like I need to run a head clean. But then the problem goes away until that colour channel "pauses" again.

I've attached a small sample of this (sorry about the photo quality) where you can see the problem at the top. This will happen even immediately after a head clean/nozzle test.

I suspect it is to do with air bubbles, but I have done everything I can to remove them from the dampers, and there seems to be no change. If it was one colour I'd suspect maybe the damper or tubing has a small leak, but this is a new machine and it is happening to various degrees on basically every channel.

Is there perhaps a way to remove air from the i3200 head itself? Could this be the cause? Working in my other job on a large format sublimation printer I have had issues with air bubbles trapped inside the head itself, however that has the effect that the print starts okay and then fades out. This seems to be the total opposite.

I'm at my wits end with this machine. We have had very little support and it is now nearly a month since I received the machine and I still have not sold one print

I really appreciate any input.

[johnson4]

4 hours ago, porl said:

I'm not sure how better to describe this, but I am running a new "Generic Chinese" printer using i3200 print heads. Everything seems to be working okay (or at least has a workaround) except for one major issue. Any time a colour channel is not used for a short time (even within one print image) it appears as though there is a blockage. After a small delay it is back to normal again. Basically, the start of any image, or the start of that colour in a region of the image, it looks like I need to run a head clean. But then the problem goes away until that colour channel "pauses" again.

I've attached a small sample of this (sorry about the photo quality) where you can see the problem at the top. This will happen even immediately after a head clean/nozzle test.

I suspect it is to do with air bubbles, but I have done everything I can to remove them from the dampers, and there seems to be no change. If it was one colour I'd suspect maybe the damper or tubing has a small leak, but this is a new machine and it is happening to various degrees on basically every channel.

Is there perhaps a way to remove air from the i3200 head itself? Could this be the cause? Working in my other job on a large format sublimation printer I have had issues with air bubbles trapped inside the head itself, however that has the effect that the print starts okay and then fades out. This seems to be the total opposite.

I'm at my wits end with this machine. We have had very little support and it is now nearly a month since I received the machine and I still have not sold one print

I really appreciate any input.

I feel your pain, I have no advice for this situation but I think we have all been there. My assumptions would be the same as yours.

 

What I do to try and purge out air bubbles or diagnose similar issues is turn up the color ink setting ( I would just turn up saturation) and make a large CMYK file of the problem color. Turn off the white ink layer and print a large block of that color. Sometimes I do 12" X 12", sometimes larger. Usually that will give an indication if it's an ink feed issue or some other issue of that nature.

Me personally, I would do a 12" X 12" block of magenta for example, then immediately afterwards reprint( like as soon as it's finished the first one). This should help make sure there aren't any air bubbles, make sure the dampers are fine and that it's not drying out at the head very quickly in a new enviroment. Two large block prints one after another, if it does it again on the 2nd one after successfully printing the first, I would assume software. If it works fine, I would assume it's drying out at the head very quickly and possibly the cap isn't seating correctly. If it still does the exact same thing on the 2nd block, I would assume software. 

[porl]

Thank you, I'll try that when I get back in front of the printer tonight. If it is software, what kind of setting do you think would need to change? I'm using cadlink of that helps.

[johnson4]

3 hours ago, porl said:

Thank you, I'll try that when I get back in front of the printer tonight. If it is software, what kind of setting do you think would need to change? I'm using cadlink of that helps.

It would unlikely be a setting but rather a driver/compatibility issue. 
 

it really looks like to me some form of air or drying of the nozzles. The test would tell I’d think. 

[porl]

Thank you, I'll be back in front of it in a few hours so I'll definitely try that test.

[anum11]

You may try to adjust printhead voltage in settings. Maybe it works with a bit low voltage for your ink. 
 

There is this setting in printexp. I dont know if all chinese rips have that setting.

[porl]

Oh, that's not something I knew of. I believe the PrintX driver/management software has head voltage settings in it. How do I know what range is safe to try? I've not seen info on this before.

It does kind of make sense though; there are a lot of "weird" things with the printer firmware - the built-in nozzle test pattern prints from halfway into the film and finishes not just outside the film area but off the whole metal platen itself, Setting the white head offset by the calibration pattern is nowhere near correct (was off by an order of magnitude), and other small weirdnesses. I've been able to work around them all, but the more I learn the better!