Ink smear on right edge and black banding issue...

[disneytoy]

Ink smear on right edge and black banding issue...

Problem: Having issues with banding in blacks and/or ink residue in white borders.

So, first, I’m printing an Epson 9890. perfect nozzle check. I have cleaned my wiper and sopped up the ink pad.

At first, I thought this was a Legacy Baryta issue. I am on the latest driver and firmware which has the Legacy setting built in. I had successfully printed a roll of 44: and 2 rolls of 24“ Baryta with no issues. As I am getting to the last 10 feet or so on a 24“ roll, I am getting (see photo) ink smear about 3/4“ from the start on the left edge of the paper. Notice the ink starts just below the image. I always print a 1“ white border for my customers, so, even if the image itself prints perfectly, I can’t deliver a print with ink marks in the border. Thinking it was the tight roll of the last feet of the Baryta, I started on a new roll to get the order out.I played around with 2 settings in the driver. Paper Thickness and Platen Gap.

PLATEN GAP: Going from standard to Wide does fix the issue. But a second problem arose. With images with large black areas, I can see “SCAN LINES” or banding. A few of my customers typically have large solid black areas. So that is not acceptable. In a standard color image you cant see banding.

PAPER THICKNESS:  I had some ink spotting issues with Exhibition Watercolor before. Random magenta or cyan drops. I was advised to increase the paper thickness. So, I am going back to STANDARD Platen Gap and think paper thickness might be more precise?

I just did a 44x70“ print on my standard Epson Premium Glossy. And at stock settings I got the same ink on the left edge of the paper. So this isn’t just a Baryta issue. The standard thickness is set to 3 ( I guess .3mm) At 4, I can still get the ink. At 5, no ink on boarder but again I’m getting the “scan lines” in the blacks. I did try to increase tha vacuum one notch in case the paper is not flat enough.

I will try to go back to 4 and see what happens.

Anty thoughts what is going on?

[hugowolf]

Definitely looks like head strikes. It occasionally happens for me too; and usually for several prints in a row, and then it is just fine for hundreds of prints. It definitely seems to correspond when near the end of a roll, and perhaps after a PK/MK switch. Since I had the waste ink pump and wiper blade replaced, it hasn't occurred. The wiper blade can look just fine but still need replacing; they aren't expensive.

I measure that paper at 0.31 mm, so a paper thickness setting of 4 should be good with a platen gap of 'auto'. When it has happened, I have added a couple of inches to the leading edge of the paper and trimmed them off after printing.

The banding looks like a missing nozzle, I would rerun a nozzle check print. It doesn't have to be the K, it could be the LK or LLK, or even one of the other colours. Examine the Y under UV light. Another thing to try would be uni-directional printing, that takes twice as long but sometimes cures banding issues.

The thing that can cause banding is a misaligned head: how long has it been since you did a head alignment?

Brian A

[bill t.]

Looks like media curl to me.  Too much for the suction to flatten out.  The inner parts of the roll are wound up tighter than what precedes it.  It is made worse if the printer sits a while with the humidity low.  If you haven't got anything better to do, roll out a few feet on a table in front of the printer and decurl it by winding it up on an empty (and very clean) core, opposite to the curl, then print right away.  If time is of the essence, sacrifice the first 8 or inches to get past the curl which is always worse on the outer parts of the roll exposed to low humidity.  I usually take the sacrificial approach, followed by printing as much as possible to sort of amortize the sacrifice.  This why we should have giant, 100 foot rolls of everything on 4" cores to run through our 48" printers.  What we have now is just so wrong...

[disneytoy]

Thanks guys!

I have a spare wiper so I might change it. No, I haven't done an alignment. Should try that.

Like I said, the banding relates to the distance to tjr paper. If I go back to standard no banding.

Thanks

Max