HP L25500 Banding

[Mr. Sign Pro]

I am getting horizontal banding in my prints when I first print after the machine being asleep. It has happened the last few days each morning when I print for the first time. It also just happened after waking the machine. How I resolve the issue is by doing a head cleaning. A head cleaning immediately resolves the issue. HP can't tell me what's going wrong and they have given me a laundry list of lame things to try such as, increasing the number of passes, wiping the media before printing, enabling extra PH cleaning, using a different profile, ect. The material I am printing on is 3MIJ35C-10 and I have been printing on it successfully since day one (almost 2 years). Anybody came across this issue?

 

[peavey123]

We had that happen for a bit. I believe it ended up having to be serviced something to do with the capping station I believe? Don't quote me on that. ha After having it serviced it hasn't happened since.

 

[jayhawksigns]

If you have the room, print color bands along the sides of the print. Had some issues with color drop out and that fixed my issues.

 

[chafro]

Change the head cleaning kit? It might be something wrong with it.

Or it might be something grown with a printing head that leaks a bit of ink when printer is off or on sleep.

Hasn't happened to me but it would make sense.

 

[Matt-Tastic]

Line sensor. If you've been running for 2 years, you're bumping up to the time when the Service Maintenance Kit should be performed. SMK #3, which includes replacing and calibrating the line sensor, was 500 bucks last I spoke with HP.

The line sensor is on the head and is what the printer uses to perform "boolean" (true/false) operations. Things like finding the edge of the material and aligning to the maintenance station to cap properly.

Yes, you can clean the line sensor repeatedly until you get the gunk off of it, but it will just get dirty again. Had a customer clean theirs for about 2 hours the other day until it would recognize a new cleaning cartridge. They've been error free for about 2 weeks since.

 

[Mr. Sign Pro]

Oddly enough it was the yellow/black printheads. They were new but not working properly. HP replaced them under warranty. I heard HP was having some issues with a batch of printheads from back in January. Everything back to normal now.