Ink drop out??? PLEASE help

[bboukari]

I'm taking all of this information in. Thank you. I'll keep you posted. I do know that there was a dent on the tubing right above the dampers on the magenta, so I went ahead and replaced it completely.

 

[gregwallace]

I'm not familiar with mutoh printers. Are the heads interchangeable? We have a vutek qs 2000 and the magenta has dropped out similarly several times. We would lose the magenta heads at a certain distance into each print relative to the amount of magenta being used. If you do a cleaning cycle in the middle of the print does the magenta come back immediately? Our magenta would. I could pretty much estimate when it would dropout and run an ink purge right before. Our magenta was lasting more like 2 feet though. Eventually we tried swapping the magenta that was dropping out with a cyan head. It works fine now. This has happened more than once and always worked for us. My theory is the magenta ink was gelled in the head and when the "gel" settled it would clog the nozzles. Purging would shake the "gel" up until it eventually settled once again. Its my understanding that magenta has the most pigment and thus more problems related to ink starvation and clogged nozzles. Not sure why the head would work with the cyan ink though. Our printer is a uv printer so this info might not help you. If possible swap the heads and see if it helps.

-probably useless information as I know nothing about mutoh printers.

 

[gregwallace]

I read through this thread again. Are both magenta heads dropping out? It looks like its just the one on the right. An air leak can be tricky to diagnose considering everything you've replaced. Does each head have its own damper? If its just the right magenta head dropping out switch it with the left. If the problem is still occuring on the right side then you must have an air leak somewhere. If the problem follows the head then you have eliminated everything and confirmed that the issue is head related. That would be the fastest way to diagnose your problem, assuming only one head is giving you problems. I believe an air leak would present problems throughout the entire print including at the start of your print. I have also had issues before on our vutek3360 similar to this. Running the printer slower seemed to fix this. If that works then you might find it better to run the printer slower on prints with lots of magenta, at least until the problem is resolved. When i say slower i am referring to the carriage speed. I lowered mine from 8 pass 40 inches per second to 8 pass 20 inches per second. It sucked but it worked. Just a thought. I hope this helps.

 

[CRD]

Greg, the colors and black for this machine are in two heads. Though swapping heads my a cure to trouble shoot.

Paco

 

[gregwallace]

Oh well there you go.

 

[CRD]

Brian, problem solved?

Paco

 

[bboukari]

I still haven't solved the issue. I'm going to be doing a bit more troubleshooting today. My fear with swapping one head with another is contamination. I'm not sure how long it will take to run the color through each. Also, wouldn't I need to swap the head rank information?

 

[CRD]

Loosen up the dampers from the head. mark the heads Switch heads. start printing right away. If the problem is in the head it does not matter what colorink it prints and it moves with the head. If it does not move with the head it is everything before the damper. head rank is for fine tuning will not effect your problem. You have to narrow down the problems. As long as the ink tubes are not mixed with other color inks the head will be clean very quick as it is a short way ofrm damper to head exit. Only a few ml's. paco

 

[bboukari]

Loosen up the dampers from the head. mark the heads Switch heads. start printing right away. If the problem is in the head it does not matter what colorink it prints and it moves with the head. If it does not move with the head it is everything before the damper. head rank is for fine tuning will not effect your problem. You have to narrow down the problems. As long as the ink tubes are not mixed with other color inks the head will be clean very quick as it is a short way ofrm damper to head exit. Only a few ml's. paco

Paco,
Thanks. Great advice. I will give that a try. What do I do with the head rank? Do I switch the head ranks since I'm switching the heads?

Today, I did replace the dampers with completely new dampers again on the magenta and Yellow. Also replaced the tubes between the o-rings, nuts and tubes between the dampers and the "y" branch on the magenta and yellow. I'll switch it with the cyan, since that head is consistently good.

As a side note, my printer completely emptied both of my yellow cartridges overnight a few days ago, so I have had to put in a new order so I'll have spares again.

 

[CRD]

just change the head ranks when you switch heads if that gives better feeling. it is not much work.
it is not ok the yellow got emptied. is the foam in the cappingstation not so saturated that it has touch the head when parked?

 

[bboukari]

Before I had a chance to do anything with the swapping of the heads, I came in and found this one day last week. It appears that at least one of my new 440ML magentas decided to take a leak through the back of the cartridge bay. I'm pretty sure it was just one and that the ink seen on the right magenta cartridge is leftover, because I remember seeing that before. The one on the left, on the other hand, was empty when I pulled it out. The ink ran down the back of the machine and all over the floor.
The machine was turned off. I am running the latest firmware.

Questions:
Could this have anything to do with the magenta drop out I keep getting?
What could have caused it?
What is the fix?