Flatbed UV Printing Color drop out Issue

[GC Decor]

Hey Guys,
We have a Fluid Color Flatbed printer (UV Ink) & just recently we have had issue with our Magenta print Head. When we start we clean & run a nozzle check & everything looks good. About 2 minutes into the run we start to get banding (Wrong term ?) In Certain Colors - I stopped the Print & re printed the Nozzle Check & Half of the Magenta head stopped printing. We have changed filters, Cleaned them, did a 10 minute Head drip. Every time we start the nozzle check is fine & after a few minutes back to the bad color issue.
I've attached three Images Below.

Any Help would be Grateful

 

[FireSprint.com]

A couple of ideas:

Is the Magenta head covered in wet ink after the banding starts? This could be a issue with negative pressure. In other words, the ink in the magenta head is allowed to drip, causing a buildup of pooled/wet ink that can be jetted through. Try improving your negative pressure.

If you don't know this already, ink is held in the printheads the same way you can pick up water with a straw by holding your finger over the top end. Negative pressure (Pressure less than the surrounding atmosphere/air) is what keeps the ink from just poring out of the printheads.

There could also be a leak, allowing air in the lines that causes the loss of negative pressure. I find this to be less common, but will require a tec to help.

It could also be an issue with static. Make sure the humidity in your room is 40-60%. You might also try wiping the substrates, and even the bed down with alcohol or an alcohol water mix to help.

 

[GC Decor]

Thanks For the Info Firesprint. No wet ink, I think it might have been an air bubble issue.
After talking with the dealer they helped us solve the head issue. Missed a step when changing the Filters. All of our other jobs are coming out fine now but this purple job is still giving us head aches.
Im gonna look into the Humidity now because in Ohio we have very High Humidity levels.
Thanks Again

 

[p10-200]

Hello i have a big problem with DURST P10-200 ouer nozzles are in very bad situation we buy new jets but in the short time they vanish or the glue come off and then when you make a purge is spitting around on printing plate and a jet dont work how it most or dont work any more.
i look for the printhead temperature and are allways around 51-52 celsium

 

[F1225hgB42w]

Hey Guys,
We have a Fluid Color Flatbed printer (UV Ink) & just recently we have had issue with our Magenta print Head. When we start we clean & run a nozzle check & everything looks good. About 2 minutes into the run we start to get banding (Wrong term ?) In Certain Colors - I stopped the Print & re printed the Nozzle Check & Half of the Magenta head stopped printing. We have changed filters, Cleaned them, did a 10 minute Head drip. Every time we start the nozzle check is fine & after a few minutes back to the bad color issue.
I've attached three Images Below.

Any Help would be Grateful

Did you solve your issue? A Fluid Color Flatbed is really just a Handtop printer with their fluid ink in it (CET, which we have is also a Handtop), we've seen this issue numerous times over the years. Here are the issues we normally see causing the issue:

1. Air in the lines - Sometimes we get air in the lines and it causes head fallout as we print but nozzle checks look great. Here is a video on how to purge out the vent tube and "burp" the lines.
2. Reset Negative Pressure Manometer - The guys at Fluid Color say they have a new negative pressure system they are using, but if your machine is older you might have the negative pressure pump above the ink system (that is where our's is). Check to make sure your negative pressure manometer is properly calibrated - here is a video on how to properly reset the manometer.
3. Negative Pressure is out of range - For our printer we have Richo Gen 5 print heads - two rows of 3 heads and run -4.5 to -5.0 if it's too high or too low we have issues. Adjust the negative pressure up or down to get to your proper range.
4. Print Mode is too fast for the ink delivery system - when we try to run in a 3 or 6 pass mode it seems that the printer can't keep up with the ink needed for the print and the printer starts to band in some colors. We have found we can't run some modes because the printer needs more ink than the ink delivery system can handle. We stay in 9 or 12 pass mode for everything we do.

Hope that helps!

 

[GC Decor]

Thanks for the Info DSGI,

We found it to be several small issues and a color demanding job. All problems we were able to fix on our end pretty quickly. We replaced the filters and forgot to burp the lines. Once we completed this, the print was much better. We also adjusted the negative pressure system, we bought our printer new 8 or 9 Months ago & I remember they saying something about the new upgraded pressure system. We found for large single color jobs, it was best to run in the high detail mode. We normally run our small jobs in production mode but the high detail mode works all around much better, Only adding a few minutes to our full sheets.

Thanks for Help