Dampers filled with a little air MIMAKI JV300

[MuhammadOsta]

Hello all..

I have a mimaki jv300-160 (2-printheads) sublimation ink set, most of the dampers are filled with ink but some of them contain air with the ink (about 1/4 air), i was planing on changing the dampers so i removed the carriage cover to have a look at them.. i tried fill-up ink many times with no luck.. soft,normal,hard.. still the same. i tried hard and ultra cleaning many times with no luck.

i wonder if someone could help me with detailed procedure about two things:

1- how to remove air from dampers

2- how to change the dampers (and not have the new one end up with air trapped inside)

the reasons why i'm thinking about changing them are:

1- banding! i have this many times.. it come and go

2- scratch-like printing.. while printing i get many scratch-like look to the print, i usually print at 1pass with perfect results.. now even three pass get bad printing (color have empty spaces like horizontal scratches not from feed adjustment)


i use the original sb53 mimaki inks and there is no ink starvation, all ink cartridges are full (i have the 2liter bulk system from mimaki, and even the bag is nearly full)

 

[Solventinkjet]

Dampers will naturally have air/empty space in them if they are working properly. The new Mimaki dampers are a little more complicated but the same applies.

What does your nozzle check look like? Missing any nozzles?

Dye sub is notorious for frying heads. If you have had these heads running Dye Sub for 2 or more years, consider yourself lucky and buy new heads.

 

[MuhammadOsta]

Dampers will naturally have air/empty space in them if they are working properly. The new Mimaki dampers are a little more complicated but the same applies.

What does your nozzle check look like? Missing any nozzles?

Dye sub is notorious for frying heads. If you have had these heads running Dye Sub for 2 or more years, consider yourself lucky and buy new heads.

the test print show no clogged nozzles.
does the print heads need to be changed if nozzles are all open?

 

[winterk80]

Not sure on the damper issue but I can comment on the other issues you mentioned.

Dye sub can we temperamental if you don't keep your humidity controlled. Are you humidfying and dehumidifying as needed? 30-50 % humidity is about the sweet spot. I set my Dehumidifer to 50 and our humidifier to 30 to maintain that range.

Banding and scratch like printing sound like either clogged nozzles or you are having head impacts where the head is dragging on the print a little, have enough of these and it can cause permanent head damage. Another reason humidity can be an issue, among other factors, is if it's too humid or you are laying too much ink, the paper can buckle enough that it slightly touches the head.

Hello all..

I have a mimaki jv300-160 (2-printheads) sublimation ink set, most of the dampers are filled with ink but some of them contain air with the ink (about 1/4 air), i was planing on changing the dampers so i removed the carriage cover to have a look at them.. i tried fill-up ink many times with no luck.. soft,normal,hard.. still the same. i tried hard and ultra cleaning many times with no luck.

i wonder if someone could help me with detailed procedure about two things:

1- how to remove air from dampers

2- how to change the dampers (and not have the new one end up with air trapped inside)

the reasons why i'm thinking about changing them are:

1- banding! i have this many times.. it come and go

2- scratch-like printing.. while printing i get many scratch-like look to the print, i usually print at 1pass with perfect results.. now even three pass get bad printing (color have empty spaces like horizontal scratches not from feed adjustment)


i use the original sb53 mimaki inks and there is no ink starvation, all ink cartridges are full (i have the 2liter bulk system from mimaki, and even the bag is nearly full)

 

[MuhammadOsta]

Not sure on the damper issue but I can comment on the other issues you mentioned.

Dye sub can we temperamental if you don't keep your humidity controlled. Are you humidfying and dehumidifying as needed? 30-50 % humidity is about the sweet spot. I set my Dehumidifer to 50 and our humidifier to 30 to maintain that range.

Banding and scratch like printing sound like either clogged nozzles or you are having head impacts where the head is dragging on the print a little, have enough of these and it can cause permanent head damage. Another reason humidity can be an issue, among other factors, is if it's too humid or you are laying too much ink, the paper can buckle enough that it slightly touches the head.

about humidity, i don't have a humidifier/dehumidifier.. however, the printer has it's own room with an air conditioner set to maintain the temperature at 25C, and i print with 27C set to all heaters in the printer.
it's been like that 2 years now, never had a problem with the prints or clogged heads. i use a high quality sublimation paper (which i choose after testing a lot of types), the paper is flat smooth on the printer and i don't leave the printer unattended while printing.

 

[MuhammadOsta]

thank you all for taking interest in this, you are awesome!

i solved the scratching problem (which was new), but still have the old banding problem when printing using the two heads.

The banding problem (one pass is darker than the other, dark/fade) is
- very old
- come and go
- sometimes it's very clear.. sometimes it's barely noticeable..

long time ago, Mimaki Representative couldn't find any clear reason why the printer making this banding until i tried to print using one head (JV300-160 has two print heads you can choose which one to use or use them both). after a lot of trials, i found that one head is spraying more ink than the other.. but that wasn't accurate, after a close look under a 60X loupe (mini microscope) it looks like it's spraying more ink but it's the "dot" arrangement that is different! one head is firing the ink dots to be "near each other" and the other head is firing to be "overlapped" (one dot above the other).. i called Mimaki Representative and explained this, they sent someone who did a "head adjustment" for the two heads.. after two days of hard work and tons of ink and paper wasted.. the problem almost gone (barely noticeable anymore). i thought "they finally killed it" but i was wrong.
it keeps come and go.. they don't know what seems to be the problem.

that's why i want to change the dampers, they never tried to change them and i have no idea if changing them will solve anything.