Excessive Banding With Mimaki Jv33

[jessica_sol]

Hi guys.

I am having problems with excessive banding with my Mimaki JV33. I started working at this vinyl/decal shop over a year ago and I remember the red always being a problem with banding but the other colours seemed fine. I'm not sure if I'm just paying attention more or if it's actually worse but I'm seeing banding in almost all the colours now. Red and purple are the worst, but I'm also seeing it in blue and even black/grey. It's difficult to tell if it's happening in lighter colours such as yellow. I'm seeing dark lines between each band, but I'm also seeing a gradual decrease in the darkness of the colour between each band. You can hopefully see what I mean from the photos I've attached to this thread. The first band is the darkest and it gradually gets lighter and then starts over after 8 bands. My passes is set to 8 in the computer and feed compensation on the printer has always been set to 6. I tried to gradually increase the feed compensation but I only got up to 12 and I didn't see much of a different with the dark lines between the bands. Does my feed compensation seem excessively low or is this about right? I just don't know how much I should be increasing it. I am using 720x720 variable dot for print resolution. Also any idea what would cause the gradual decrease in darkness per band? Any suggestions would be great! Thanks!

 

[Andy_warp]

Are you printing through rip software...or just local to the printer from an Adobe application?

Maybe do a jet test to check for blocked nozzles. A picture of that may be useful to post here too.

This could also be a printhead alignment issue. There are actually a ton of things it could be.
Does your printer get used every day? Ink can gum up from just sitting...

 

[31legen]

What firmware are you running. The latest firmware with the "maps" update really helped the mimaki machines with banding.

 

[Solventinkjet]

The nozzle check should show us what's going on. I'm thinking you might have some cross contamination going on and/or ink flow issues. Also, with the print feed compensation, moving the setting 6 points is not going to show up very well. I always move in increments of 10 until it's close and then fine tune it. Even 10 points barely will move it. Are you basing your print feed adjustment on the actual adjustment print or just adjusting based off the real prints?

 

[jessica_sol]

Are you printing through rip software...or just local to the printer from an Adobe application?

Maybe do a jet test to check for blocked nozzles. A picture of that may be useful to post here too.

This could also be a printhead alignment issue. There are actually a ton of things it could be.
Does your printer get used every day? Ink can gum up from just sitting...

I am using Production Manager for rip software.

We use our printer Monday-Friday generally everyday.

I did a nozzle check print and there were a couple lines missing and after I did a nozzle clean everything was good with the test but problem still persisted.

 

[jessica_sol]

The nozzle check should show us what's going on. I'm thinking you might have some cross contamination going on and/or ink flow issues. Also, with the print feed compensation, moving the setting 6 points is not going to show up very well. I always move in increments of 10 until it's close and then fine tune it. Even 10 points barely will move it. Are you basing your print feed adjustment on the actual adjustment print or just adjusting based off the real prints?

After I posted this I did larger feed compensation adjustments going from like -60 to +60 and nothing changed in regards to my problem. I could see what changing the feed compensation was doing but my problem persisted no matter what. I will do the nozzle check again and post it. I thought it looked fine but then again, I'm new at all this so maybe I'm missing something. Thanks!

 

[jessica_sol]

What firmware are you running. The latest firmware with the "maps" update really helped the mimaki machines with banding.

I wouldn't have a clue. How do I check?

 

[jessica_sol]

Here's the nozzle check. Hopefully you can see it alright.

 

[Andy_warp]

Is this happening on all medias? Can you recreate the problem on a fresh roll of material, or another substrate?

 

[jessica_sol]

Is this happening on all medias? Can you recreate the problem on a fresh roll of material, or another substrate?

All media I believe. I'd have to test different media to be 100% certain. It happens on all the vinyl we use (new rolls don't make a difference) but I can't recall if it does it on our banner material.

 

[particleman]

You need to eliminate media comp issues first. Adjusting the comp on the fly requires waiting several passes to see a difference. A better way is to use the stand alone media comp test in the media settings menu I'd you aren't comfortable using the on the fly method(see manual it has been 8 years since I used this machine). It will lay black only and is much easier to see what is going on. Be sure to tape on the roll also. If I remember the setting needs to copied to the value you adjust while printing if that makes sense.


Assuming your media comp is correct my next thought is that your heat settings are not correct and/or you are laying down too much ink. Make sure your heaters are all working and set correctly. Is the switch ON? Try adjusting the heat a few degrees hotter. If you were right on the edge of correct settings before to get a decent print a small change in environmental factors (indoor temp/ humidity) could require a tweak.

 

[jessica_sol]

You need to eliminate media comp issues first. Adjusting the comp on the fly requires waiting several passes to see a difference. A better way is to use the stand alone media comp test in the media settings menu I'd you aren't comfortable using the on the fly method(see manual it has been 8 years since I used this machine). It will lay black only and is much easier to see what is going on. Be sure to tape on the roll also. If I remember the setting needs to copied to the value you adjust while printing if that makes sense.


Assuming your media comp is correct my next thought is that your heat settings are not correct and/or you are laying down too much ink. Make sure your heaters are all working and set correctly. Is the switch ON? Try adjusting the heat a few degrees hotter. If you were right on the edge of correct settings before to get a decent print a small change in environmental factors (indoor temp/ humidity) could require a tweak.

I played with the comp much more aggressively after I made this post adjusting it from -60 to 60 on the fly. I could see what changing the value was doing but it didn't solve my problem. I will try to play with the heat settings next. The temperature and the humidity in the room is greatly different season to season so maybe the transition from winter to spring here is messing with it. Thanks for the suggestion!

 

[basstrax]

Did you ever get this issue resolved? I'm having similar issues.