L25500 Vertical Banding lately?

[MIMO]

Anyone out there experiencing vertical banding on their L25500s lately (we are obviously)? And I mean newly experiencing it where you never had a problem before, maybe since doing the latest firmware update.

It's the 21mm bands that they introduced the vertical correction feature for in 2010. We know where and how it happens, the media lies unevenly on the platten so either too much heat or too much vaccuum are obvious culprits, but #*&$ if we can get it to go away. And it's happening on banner, SAV, and even poster paper.

Never had it before, used to be able to print light greys so beautifully and now it's a joke with all light colors (solids are good).

Anyhow, if you're having the same issues, I'd appreciate knowing.

 

[jayhawksigns]

Not having any issues here.

Only time I have problems is when I am testing new substrates, especially items that I think won't handle the heat well and the passes run together since the heat was too low.

 

[MIMO]

Thanks.

 

[Typestries]

Try cleaning all the platen vac holes.....use a small drillbit. Blow em out with air. Also the platen vac fan blades get gummed up with overspray affecting vac across he platen and need to be cleaned. Another thing HP never anticipated.

 

[Suz]

Okay, dumb question here, which way is vertical banding?
I ask because we've had banding problems off and on since day one. But we started with bad heads and didn't know it. Recently, more banding problems just before a head failure last Thursday. Replaced the head Friday and it is working again with no banding.

Does vertical go left and right across the material as it comes out of machine? Or is it top to bottom? Our banding problem was happening from left to right as you are facing machine.

 

[Tim Aucoin]

I would say that vertical banding is top to bottom vs. horizontal banding which would be left to right coming out of printer...

 

[Suz]

Thanks Tim! I mean thanks, Skinny!!!

 

[signswi]

Started seeing it on thin cast vinyls printing light solid colors (i.e. a flood of cyan). Going to be cleaning out the platen holes tonight as Type suggested.

 

[dypinc]

Usually this vertical banding noticeable in light solid colors is caused by too much vacuum.

 

[Suz]

signswi, let us know how that goes. I'll be following your procedure when I need to!!! Right now my machine is running beautifully. Fingers crossed!

Started seeing it on thin cast vinyls printing light solid colors (i.e. a flood of cyan). Going to be cleaning out the platen holes tonight as Type suggested.