HP Latex Undetermined Head Issue

[AMondor1]

Please help!
We have been struggling we a head issue lately with our Hp 365. The struggle has been with with printing blues and reds. When we do all the head tests everything is fine. But when printing full width panels(54") we have either really bad banding or complete color loss. I have attached a photo of our most recent issue. The right panel is the correct color, but the left panel is far more pink.

Because of the colors affected and results we believe it could be a yellow magenta head. Both heads are out of warranty but one has had only 1.5L go through and the other has had 3.0L. Typically we have been able to run heads to 4.5-5.0L.

Right now we are trying to just replace both heads in hopes that fixes it but not being able to exactly diagnose is really frustrating.
If anyone has run into this significant of issue and been able to identify its cause please share.

 

[BigNate]

...new printheads is good idea so you are starting from a known point - but how about a profile with more passes? the more passes you use, the less banding you will have....

 

[Jayefkay531]

Please help!
We have been struggling we a head issue lately with our Hp 365. The struggle has been with with printing blues and reds. When we do all the head tests everything is fine. But when printing full width panels(54") we have either really bad banding or complete color loss. I have attached a photo of our most recent issue. The right panel is the correct color, but the left panel is far more pink.

Because of the colors affected and results we believe it could be a yellow magenta head. Both heads are out of warranty but one has had only 1.5L go through and the other has had 3.0L. Typically we have been able to run heads to 4.5-5.0L.

Right now we are trying to just replace both heads in hopes that fixes it but not being able to exactly diagnose is really frustrating.
If anyone has run into this significant of issue and been able to identify its cause please share.

These printers are notorious for color shifts in blues especially, and gradients, when tiling prints. This looks like that would be an issue. Is the background a pms color or cymk save file?

The banding you mentioned is likely a head issue. On these printers an 8p or 10p should give near flawless prints. A head test is one quick pass so could still look great. Send over a print file with (6) 8" x 36-48" color swatches lines vertically. Each swatch should be 100% of the head color ( 100%c, 100%m, etc). Over 36-48", you'll see if one head color is dropping out prematurely.

I have the l360. HP only warrants for 1000ml. I usually get 3500-5000ml in each head before noticing any errors, sometimes over 10k. However, I've also had some that needed replacement at 1500ml.

Id start with the print test, then swap out heads and try again. If the print test looks good, then it's likely a print file output error, not a hardware error.

 

[RickP]

Have you logged into your printer and look at the service support report?
It shows the number of nozzles that have issues in each print head.

 

[citysignshop]

Hey gang....just a new 365 user, trying to learn to troubleshoot! If the head 'works' for one side, why would it be bad just at the end of each pass?
1. What if you ran a test with the heat 'off'. that would eliminate uneven heating.
2. If the optimizer isn't being applied uniformly, would that not effect the colour?
3. print on other media, like paper or banner, something that would show a different level of ink reception? I've had rolls of media where some contaminants caused serious colour shift....the first 10' of vinyl was sprayed with some crap at the factory!

just throwing these out there, see what sticks, right? good luck!

 

[balstestrat]

Don't make it too complicated, if you have an clear issue like that just replace the printhead and continue making money.
Spit bars on the side make it usually pretty easy to see if the issue happens on some color only.

 

[Terrance the Deuce]

IMO there is a high probability this issue will go away when you replace the heads. The issues you are describing are prime examples of what happens when the heads are going bad on a Latex. You can probably run a head test to see which head(s) specifically are having an issue. I don't know what your rip/color management situation is, but anytime someone mentions inconsistent color I recommend creating your own media presets for individual medias and your own color profiles for each media. Color consistency is achieved by doing this and recalibrating regularly. On a Latex, run the color calibration every time you replace a head, and at least once a month.