Cyan and Black on the left channel stop firing during production.

[mustafade]

Hello Everyone,

I just finished a 330" banner printing, 165"x2 non stop.
I noticed a color shift on the print out where 2 or 2.5 feet was left to finish the job.
As soon as it finished printing, I did a test draw and there it was, no CYAN and BLACK on the left channel.
Afterward, I did a normal cleaning and they came back. Is this a indication of it needs a capping station alignment?

Thanks for ya'll s input.

 

[Gabriel]

Maybe you'll need a new capping station. If the problem will come back shortly after a manual cleaning, then you'll have to replace that.

 

[Rooster]

There's also an adjustment for head refresh rate you should check. It determines how often the head returns to the capping station to refresh the ink in the dampers. Your long run may have depleted the available ink from the dampers until you did the cleaning.

 

[mustafade]

There's also an adjustment for head refresh rate you should check. It determines how often the head returns to the capping station to refresh the ink in the dampers. Your long run may have depleted the available ink from the dampers until you did the cleaning.

Good tip! I'll check on that. Any idea what it supposed to be vs what it should be?
I talked to a technician he said that if it is stop firing during printing it can't be the capping station, he said that I should check the o ring on the mount brackets for dampers because there might be air leak because it can't contentiously draw ink during the printing.

 

[Rooster]

Good tip! I'll check on that. Any idea what it supposed to be vs what it should be?
I talked to a technician he said that if it is stop firing during printing it can't be the capping station, he said that I should check the o ring on the mount brackets for dampers because there might be air leak because it can't contentiously draw ink during the printing.

I'm not sure what it should be set at, or even what printer you have. My JV33 is set the same as it was when it was delivered and I haven't had any problems. Your dealer should be able to walk you through changing it over the phone. If it was working correctly before, then changing the head refresh rate will probably just be masking the underlying problem.

Checking the dampers is always the first thing to check when you're dealing with ink delivery issues during printing. If the ink disappears after sitting for awhile then it's usually the capping station. Although an improper seal at the capping station can also cause the head refresh to work incorrectly as the pump won't be able to draw ink through the head to refresh the dampers if the seal at the capping station isn't correct.

 

[Neil]

It'd be something above the head, not below it.
Sounds like partially clogged dampers or something restricting the flow - causing ink starvation on a long run.

Being that 1 normal cleaning brought them back, the cap seal seems good.
As Rooster said: check the dampers.

 

[lmmnsr]

What is the correct printhead height....MIamaki CJV30?

Hi again everyone, I replaced my printing head on my Mimaki CJV30-160 and I was hoping someone can tell me what is the correct height measurement without any media mounted?

 

[mustafade]

I'm not sure what it should be set at, or even what printer you have. My JV33 is set the same as it was when it was delivered and I haven't had any problems. Your dealer should be able to walk you through changing it over the phone. If it was working correctly before, then changing the head refresh rate will probably just be masking the underlying problem.

Checking the dampers is always the first thing to check when you're dealing with ink delivery issues during printing. If the ink disappears after sitting for awhile then it's usually the capping station. Although an improper seal at the capping station can also cause the head refresh to work incorrectly as the pump won't be able to draw ink through the head to refresh the dampers if the seal at the capping station isn't correct.

Checking the dampers is one of the first things I did.
It seemed they were low, low being little more than half full in the dampers.
Problem is still there, I haven't resolved it yet. Next thing I am gonna try is to check the refresh rate.

 

[mustafade]

Hello everyone,

Although the thread title says Cyan and Black but any given color and channel is having the same issue.

I am still having the same problem. However, I noticed now it takes more than one time NORMAL Cleaning cycle to get the colors back.

Do you think it is an capping station alignment?

The reason I am leaning towards this way now more than ever is when the tech was done and gone fixing my problem which was exactly the same problem, 30 to 45 min later it did the exact same problem and I called the tech on his cell phone and he had me adjust the capping station over the phone.

Any inputs?

I am kind a desperate to get this fixed on my own now.

 

[SightLine]

Cannot remember for sure but I seem to recall your machine is a JV33 correct? If so there should not be ANY air in the dampers. Totally opposite of the JV3 which typically has dampers half full. Main thing I would check beyond that is the head refresh rate. In Flexi you can set the head refresh rate job - on jobs with very heavy ink coverage I do generally bump the refresh up to two to make sure it does not starve for ink. On Flexi on the driver tab when sending a job - you can set the refresh from 0 (no refresh during the job) to 3. Typically we leave it on 1 all the time but on the heavy coverage jobs often bump it to 2. I've never used it on 3. I imagine you can set this on the control panel as well.

 

[mustafade]

Cannot remember for sure but I seem to recall your machine is a JV33 correct? If so there should not be ANY air in the dampers. Totally opposite of the JV3 which typically has dampers half full. Main thing I would check beyond that is the head refresh rate. In Flexi you can set the head refresh rate job - on jobs with very heavy ink coverage I do generally bump the refresh up to two to make sure it does not starve for ink. On Flexi on the driver tab when sending a job - you can set the refresh from 0 (no refresh during the job) to 3. Typically we leave it on 1 all the time but on the heavy coverage jobs often bump it to 2. I've never used it on 3. I imagine you can set this on the control panel as well.

Yes it is a JV33. There is always air in the dampers. I attached a picture how they pretty much look.
Yes I can set it as well. Some of my profile settings were at 0, so I bumped all of them to 3 for now.
Strange thing is thou when stop firing in the middle of a print job the ink level in the dampers are still the same as in the picture I attached.

 

[mustafade]

Maybe you'll need a new capping station. If the problem will come back shortly after a manual cleaning, then you'll have to replace that.

I changed the capping station about a month ago.

 

[SightLine]

My guess is you are having a pressure issue in the ink system due to the air in the dampers. On these machines (JV5 as well) the dampers shoudl not have ANY air at all in them. If there is there will be pressure issues when printing at high speeds or high ink coverage. It will probably work when slowed down and set the refresh high but it's going to be an ongoing problem. These are very sensitive the the pressure in the lines. I will also say from experience- getting the air out of the dampers is a major pain in the rear. I pretty much filled a big glass dish with washing liquid and using a syringe and tube dunked them - while holding the side valve on the damper open to get mine totally filled with no air when I changed the dampers on mine several months back.

 

[mustafade]

I talked to a Advantage Sign Supply tech yesterday he thinks that it is an electrical problem and he thinks that the other tech who worked on my printer misdiagnose the problem.
He thinks that the trailing cable is needs to be changed but I am not convinced.
I sent him the same picture I post it here, he says that much air in the damper isn't uncommon and he says it is a total considend that when you do a cleaning during mid printing colors are coming back.
Go figure!