T-Shirt Forums banner
1 - 9 of 9 Posts

·
Registered
Joined
·
93 Posts
Discussion Starter · #1 ·
Hi guys,

First I just want to say that my printer has nothing to do with DTG, it is a flatbed UV printer. However it is based on Epson 4880 and since I know some of you are using this model I hope somebody can help me.

Sorry if I choose the wrong forum for my question but I could not find any related to UV or just general problems with printing.

When I print with bi-directional mode I am getting some vertical ghosting on my prints. It does not change if I print with high or low resolution it only changes when I turn off bidirectional mode.

It is not very bad. I actually noticed it only when I tried to print a rectangle drawn in vector graphic 0.176mm line around it. And one more thing that the closest to the printer home position line of the print does not have any ghosting but the one 10 cm further printed twice with about 0.5 mm distance between.

I have tried aligning the print head but it helped only a little. I would try alignment again but the pattern printed with manual alignment is printed actually twice for each set and I am not sure which one I should use for each set of each colour.
Auto alignment does not work since it is required specifying the thickness of the media and because it has been converted to the flatbed printer it does not want to start.



The guys who have made this printer recommend to turn the printer off to fix ghosting but it does not help at all.

The encoder strip has been cleaned to make sure there is no dust or ink on it.

I can post some pictures if it can help to solve the problem.
 

·
Registered
Joined
·
93 Posts
Discussion Starter · #2 ·
I have forgotten to mention that nozzle check is good. There is no vertical/horizontal banding in my prints. Also if I try to print 10-12cm further from the home position both the left and the right lines have ghosting in them.
 

·
Registered
Joined
·
804 Posts
This machine is probably very close to our Flexi-Jet Printing System since it is based on the 4800/4880 platform. How far away is the print head from the product? When the print head is farther away from the product, there is a possibility of it printing double. You want to be as close as possible without letting the print head strike.

Also, it sounds like your bed or platen may not be absolutely level. I would look into that.
 

·
Registered
Joined
·
533 Posts
Bi directional alignment issue, the problem is this can be very difficult to do when you have 3rd party inks installed (especially if some are white).

You will find if you can get the head closer to the media the problem should get better, as Kevin said.

But if you cant get the head closer to the media and or do a Bi directional alignment, then run it in Uni will be your only option.

Best regards

-David
 

·
Registered
Joined
·
93 Posts
Discussion Starter · #6 · (Edited)
Actually it seems to be a problem with some ink line( I believe it is black) It may be not sealed 100% and there is some air coming with ink.

I tried adjust belt tension but it was with air in lines so it did not help at all. I will try to do it later when I find where black line is bad. I print quite close to material and ghosting happens only with black and all the time in bidirectional mode. So it cannot be wrong distance, otherwise all colors had ghosting. The bed was not perfectly leveled but I adjusted it and had the same problem with black ghosting.


After I do power cleaning and purge the ink from cartridges in all lines then ghosting is almost gone.
I figured it out when black in nozzle check turned into dots instead of lines while all other channels are prefect. And I also noticed some dark ink on top of the head carriage. I believe that may be leaked from black line during power cleanings I had done before.


So far power cleaning helps but each power cleaning takes about 150-200ml of ink and when inks cost you $200/L that is very expensive way to clean the head or fix just one bad channel.



I am in the process of checking all lines for tiny holes or cuts or may be some bad connection to dampers but it is not that easy with the system that already has inks in it. I can see some bumps on a few lines which seems to be caused by the print head ribbon cable. The cable edges are quite sharp and it sits tight sometime pushing ink tubes with the edges. I have moved it away from the ink tubes.

And yes David, you are absolutely right. It is almost impossible to do any adjustments like print head alignment with 3rd party inks and the printer modified into flatbed one. I have tried to do it but it does weird things like printing two sets for head alignment or hitting the left side of the printer case.

Even when you just try to print without supplied by MFG software it does not do it properly. And one day I tried to do Sonic cleaning built into 4880C and available from a special mode of the printer menu but the printer says it cannot do it with non original cartridges.
 

·
Registered
Joined
·
804 Posts
What brand/model is this machine and what brand inks are you using? Also, if you have done any maintenance on the machine, did you take the ink lines off? If you did, did you remember to put back in the little black "O" Rings?
 

·
Registered
Joined
·
93 Posts
Discussion Starter · #8 ·
What brand/model is this machine and what brand inks are you using? Also, if you have done any maintenance on the machine, did you take the ink lines off? If you did, did you remember to put back in the little black "O" Rings?
It is BrotherJet, model called Mini UV. They say the inks are from US.

No I had not done anything with lines connections to the printhead before this problem started to happen. After that I checked four lines including black and I could see O ring on both sides of a 90 degree connector.

But I thought the connector for the black ink was not sitting tight and close to the damper tubing so I pushed it further into the damper and tightened all screws.

So far black ink seems to be delivered without any air. The nozzle check for black is great and even printing in biderectional mode is aceptable for black. I will keep an eye on it. Before it seemed to be getting worse if the printer was not used for 2-3 days.
 

·
Registered
Joined
·
93 Posts
Discussion Starter · #9 ·
Just want to post an update on how did it go after checking and reconnecting some ink lines.

It seems that it was a problem with unsealed black line because after I checked all connections and tighten all nuts on four lines(one set of colours) that sits on the same side of the printer where the black is) the problem with air in the black ink line is gone. It is printing very well even after siting idle for more than 48 hours. Before I had a lot of problems after 12 hours. And the ghosting is almost gone in bidirectional printing. It still needs some checking on the carriage belt tension to eliminate small amount of ghosting that happens but it is not as bad as it was before.

Thanks to everybody who has been trying to help me with this problem.
 
1 - 9 of 9 Posts
This is an older thread, you may not receive a response, and could be reviving an old thread. Please consider creating a new thread.
Top