Help with magenta ink! Mutoh VJ1614

[ndowd]

Ok, I am trying to run a very small print and keep losing the magenta about half way through. I can run a cleaning and recover the nozzles but half way through the next print I lose it again.

The tricky part here is that after running the cleaning I ran two 53"X12" blocks of pure magenta without fail.

The print in question is printing to an 8mil vinyl and is quite heavy coverage in black which i had thought might be clogging the nozzles. I lifted the print head hoping that would help and was able to get through one print but not a second before losing the magenta again.

I have been printing all day without issues until now. I have also changed the magenta cart.

Does anyone agree that it is just too heavy on the already heavy vinyl? If this were the case would I not see some sort of defect in the print, like a head strike?

 

[ndowd]

I just ran a test on a thinner media with the same result

 

[ndowd]

Ok, I just ran two other prints without an issue on the same media with the same settings. So far the original file is the only one causing a problem. Could there be anything in the file that would cause this? I get one here and there that print well but when i lose the magenta i have to run a cleaning to get the nozzles back. Any suggestions?

 

[heyskull]

This sounds like a damper or a leak in the magenta line.

SC

 

[Sign Eagle]

We have had the problem with a Falcon II the past few months, we found air int the tubing between the cartridge an the head. With our machine if you run the head to the left as if you were to cange the wipers and take the left cover off, you could see air bubbles in the clear tubing. We used a syringe right there at the head to pull the air out. The problem was caused for us when the cartridges run out of ink with out any indication other than the color stops printing, never had that problem till they change the cartridge design.

 

[ndowd]

I would agree though I just completed a 48"X36" print without issue and then ran the other file and did not get half way through it before the magenta was gone again.

 

[artbot]

first off ink starvation is what i sounds like. can you take a picture of the issue, and a picture of a test draw immediately after the drop out? if all other colors are fine, it's unlikely you have a vacuum/priming/pump issue. manually pull some ink at the magenta damper/s. does the flow to the syringe seem under strain, and does the membrane on the damper stay concaved or does it relax after pulling ink?

 

[ndowd]

Ok, here are some pics I took this morning. The first one is my problem child, the second is the roll of prints that I ran this morning without any problem or hiccup whatsoever. I am not troubleshooting genius but I have a hard time thinking that this is mechanical when everything else that I print is beautiful.

 

[randya]

Try another wave.
Or perhaps another profile.



You can also do a clean during print, that may get you by this job.


How old is your VJ?

 

[ndowd]

I will try some different profiles.

As far as cleaning i need to print 100 of these bugers for a print and cut.

VJ is less than a year old.

 

[randya]

You can still do a cleaning during print.

If it is only happening on one file, it can be related to profile,wave, etc.
One way to check this is to make it drop out with this file, stop the printer without allowing it to return to the capping station and examine the bottom of the head.

If there is a puddle of ink on the magenta nozzles that keeps ink drops from performing correctly then it could be some kind of harmonics going on.

Changing the wave should help as well as a profile that will pick a different ratio of small/medium/large drops.

I have not seen this on VJ's, but I have on other printers, very rare though.

What RIP are you using.

If you have this issue with more than just this file, then you should contact your dealer and get it documented. Had it happened with all your files and especially the solid magenta then it could be dampers or even the head. But one file....probably not.

 

[ndowd]

Thank you, I will look in to that and post with results.

I am using Flexi Sign Pro 8.6

 

[ndowd]

Oddly enough I went back to replicate the issue, which I have not had any problem doing in the last two days, and the graphic printed well several times in a row.

After a couple of good prints and no changes to the settings I took a chance and printed the job and it ran without a problem.

I am extremely confused at this point but at least the job is done!

 

[ndowd]

Thanks to everyone who posted with tips!