Anyone experiencing weird black horizontal banding on HotPress?

[pixeldoppelganger]

On my 11880 and 9900 I'm seeing a weird horizontal banding, but it's not the 'normal' banding that one might see with clogged nozzles, paper feed issues, etc

Its more of a horizontal 'marbling'   only with matte black ink, both printers, on 2 different batches of Epson HotPress Natural. 
I've run paper feed adjustment tests, nozzle tests, head alignments

I'm stumped. Anyone experiencing something similar? Bad batch of UltraChrome Matte Black ink?  I will admit these inks were bought via Ebay, but brand new and sealed.  Hopefully not a wave of grey market, counterfeit inks coming out

frustrating...

[MichaelWesseling]

Only visible on the hot press or also other matte paper? First ever used hot press ?

I use the hot press on the 3800 without issues.

[pixeldoppelganger]

I'm ruling out a bad coating batch of the HotPress. 2 separate batches, same problem.
I'm narrowing it down to a residue of AccuRip that was installed  (used the black only and poured out the black ink for films)

or a bad batch of Black ultrachrome ink.

Running a large black swatch on the paper now, increasing the platen gap from wide to widest. Want to eliminate any possible scuffing or touching...

still puzzled, if problems continue tomorrow. Decision One will have to figure it out

[pixeldoppelganger]

Last hypothesis....

We're thinking the Accurip software we installed (2 different locations, 2 different machines) may have caused some print head issues.  The feature we liked (during our trial purchase) was that for inkjet films, you could control the droplet size and how much ink you could pour out the printhead onto film.

I've read the Epson heads can get damaged from overheating w/ lack of ink. Ink acts as a coolant.  I'm wondering if way too much ink can insulate prevent the cooling, and still damage the head.

Does the matte black and photo black inks, jet from the same position on a 9900 and 11880?  (I.e. they share the same dual print head)

Decision one coming out, Epson thinks it's the print head.  I'll know once it's replaced....   
if this is indeed the fix... then watch out for third party rips like this....     (over driving the ink output)

[davidh202]

I actually thought I had a similar problem with a 24"roll of Hot Press Natural last week while printing a limited edition run of a clients  'Panda' original (large black areas), but after drying overnight what had appeared to be  slight banding in the blacks disappeared.  .
Info sheet with the paper says to allow for 24hours dry time.

 

[Farmer]

In the 11880, MK and PK fire through different channels on the head.  On the 9900, they share the same head channels.

What media settings are you using?  Have you used this media before?  When did you last use MK?  Is the ink within expiry?  Have you tried shaking the carts to help to guard against pigment separation?

Can you post an pic of the problem?

[pixeldoppelganger]

Ok good to know that the 11880 uses different channels for the matte and photo.    This eliminates the theory that the rip may have over driven the nozzles. 
However, on the 9900 it still could be true.

The fact that it's occurring on both machines is now making me think it could be the ink.
But the odds of both machines having the ink separate out is remote.

The ink has dried on the HotPress, yet the streaky bands are there.....

I'll try to scan a section today to upload so everyone can see...

[pixeldoppelganger]

ok, it seems after reading posts on the Yahoo Groups forum, that the banding I'm experiencing is a known problem for some users.

My 9900 and 11880 are both experiencing this black banding.
I'm going to try the following

increase the humidity
slow down the drying passes
print in 2880
tweak the paper feed adjustments   
raise the left side of the printer under blocks to aid in the ink delivery

if all this fails, I'll look into replacing the ink pump and the print head. Out of warranty costs, I exceeded the 3 year extended!

-I'm seeing this in photo black and matte black inks
-none of the forums including this one, have posted any real epson solution. It seems too many factors can cause this known and documented problem.
-finally, my 9900 for 3 years never had this black banding!  My 11880, which is 2 months old, has had this issue from the start...

Any other advice???

thanks

[pixeldoppelganger]

update to the above post:


User Davide in Italy just responded. It does seem this entire black banding is based on a faulty ink pump.
I'll copy a section of his email
>>

1. They changed the head - useless, expensive.
2. They changed the dampers - useless, cheap.
3. They played with paper feed and tension, aligment,  - not completely useless, but the problem evidently was elsewhere.
4. A super-technician was called (to get his mobile phone number was more difficult than kiss the pope's hand at the Vatican). He ran few tests then declared: the pump. And went away.
5. Normal technicians got back, changed the ink pump, ran some aligment test (with wide Platen Gap), and finally everything was ok.
>>


I update the group my experience after this part gets replaced

[a.lorge]

Pure speculation here but:  It sounds like the printer is laying down too much ink on the matte black channel.  What happens if you print a black patch on the hot press paper, but use a media setting with a low ink limit (like uncoated paper or something similar)?  Still get banding?