Strange blue random lines of varying width showing up in the same area

[jim wells]

The past few days I have noticed strange blue vertical running lines that vary in width through the middle
of prints. Usually it only prints them on a colored background and not so much on the white background.
They are always blue and in the same area horizontally. I assumed it must be the encoder strip and cleaned it. It seemed to lessen it but it is coming back. My printer is a vs540 btw. Any ideas?

Pics....

 

[Joe House]

Good thought. I would say encoder strip as my first guess too. You might try cleaning it again. Sometimes you just move the problem (contaminates) down the strip. I usually clean in one direction and use a couple of alcohol wipes to get it done.
If that still doesn't fix it, I would suspect a ribbon cable somewhere is cross talking with another cable. Look at where you have multiple ribbon cables and make sure that they are lined up neatly.

Good luck,

 

[jim wells]

Cleaned encoder strip a few more times, checked cables.
Still have the issue in the same area on the material.
but then I print a 20' long camo pattern that takes up most of the width and not a mark anywhere.
The mark is always only blue.

 

[XL_poster]

Hi! I've exactly the same problem, but with magenta, only when print big yellow patterns.
vs640 , also cleaned encoder several times but no reslults.

 

[billsines]

So I've had problems kind of like this with my laser...it has an encoder strip as well. Cleaned many times, kinda took care of it for a day, then back to the same problems. Turned out to be the little pcb board on top that reads the encoder strip. Not sure that principle crosses over for your printer problem, but just thought I'd throw it out there.

 

[Joe House]

It could be the sensor, but since it happens in the same place, i don't think it's likely. The encoder strip could be damaged there. You can flip it end for end, keep the same face forward and the holes will line up for the mounting hardware.
Or it could be the cables running up to the print carriage - one could be damaged and shorting out at that location, sending a signal to fire cyan.
But since it seems to match up with what you're printing, I'd go with flipping or getting a new encoder strip.
Good luck

 

[JTBoh]

If it just happens to appear on the white, you can sometimes save the print by wiping the ink off with alcohol before lam. Good luck.

 

[jim wells]

Haven't found my problem yet. But when I switched to uni-directional it went away?

 

[jim wells]

So when I print in Bi-directional I get the random blue print. When I print uni-directionally I have no print issues.
That tells me it is printing on the right to left pass ok and when it prints left to right I have the issues.
Any Takers??

 

[Tattoosleeve]

Does your printer have media clips? Maybe the left clip is warped and making contact with the head on the back pass causing ink displacement and transfer to the media? Happened on our Epson before.

 

[jim wells]

Does your printer have media clips? Maybe the left clip is warped and making contact with the head on the back pass causing ink displacement and transfer to the media? Happened on our Epson before.

Thank you for you suggestion. I have plenty of clearance on both passes.

 

[Wizard Signs]

Having same issue with my printer. Cleaned encoder, changed cable cards, capping station.......Will try unidirection.
I noticed XL_poster mentioned same issue but with magenta when printing large amounts of yellow. Mines started with cyan whiles printing 12mil poster paper. Later black did the same but worse. Its wide as what ever file i print. Vertical black lines.

 

[Solventinkjet]

These random patterns are caused by a short in the head signal circuit. If you've changed the cables, the only thing left really is the head itself, or the main board. I usually like to air dust the terminals that the cables plug into just to rule out and debris causing the short.

The head signal is created by the CPU and then amplified to reach the proper voltage for the head. When there is a short it basically just sends 100% voltage to the head which is why it fires all over the place. If it's intermittent, that usually indicates a cable. If it happens all the time, it's either a cable, head, or main board.