White dots appear on the print - Mimaki SWJ320EA

[ssb1923]

Hello

I have Mimaki SWJ320EA Solvent printing machine. We do not have any nozzle loss. In the last week, white spots started to appear on the print as seen in the photo. I have the same problem with different designs. I tried many things like cleaning but the problem is not solved. If anyone has any ideas I would be very grateful. Thank you.

 

[Smoke_Jaguar]

Strange, does the SWJ-320EA even have white ink? Could be some sort of contamination if not.

 

[ssb1923]

Machine does not have white ink.

I cleaned the heads and caps with solvents. I reviewed the Droppos settings. The service was also unable to resolve the source of the problem.

 

[Smoke_Jaguar]

Are the white spots missing ink, or is it some sort of contamination? Hard to tell by the picture.

 

[ssb1923]

İt is missing ink. I tried with different colored materials. I'm sure the materials are clean too. the result was the same

 

[FrankW]

This cant be a problem of the printer. There must be missing nozzles for every ink channel, with every pass at the same spot on the media while working good inbetween. Never seen such a coincidence in 25 years of large format printer support.

It must be a problem with the media. Sometimes these things happen because of dust, sometimes because of some other dirt on the media like oil, silicone or whatever. Shure if it happen on different kinds of media? The only thing were the machine itself could be the problem is if someone have greased the carriage rail with to much oil, and this will spilled on the media while printing.

 

[ssb1923]

I will try with canvas and paper tomorrow. I will also check the rails and the cleanliness of the table as you said.

 

[netsol]

it's not as simple as dust from hot air heat, is it?

 

[ssb1923]

I don't think it's the temperature. ambient temperature is stable. We have been printing under the same conditions for a long time and it has started for the last week.

 

[netsol]

hang up a humidity guage?
you might need one of those odd, antistatic wands over the vinyl feed
(i bought one but never ucessfully used it)

 

[Smoke_Jaguar]

I've seen similar weirdness with flatbed UV printing from static electricity, but that might just be an issue with the material.

 

[unmateria]

Its usual with some bad media. Try other vynil/paper.