Platten Gap Causing Marks on Print?

printer

#1

Hello,

I am printing with a 9880 recently purchased from an an independent Epson service tech that has a new print head and pump cap station.

The printer is printing well, but I occasionally get tiny black marks on the print that occur in two rough lines about one third in on the right and left sides of the carriage on 36" wide paper. The marks are 1/4" to 1/2" tiny, inconsistent dot patterns and not the ink blotches I have seen from other Epson printers.

Typically I would guess the marks are caused ink build up on the print head, but the Epson tech says there is no way ink could have built up on a brand new print head and capping station. He said I should set the Platten Gap wider.

I do see a little ink build up on the bottom of the wiper blade and pump cap station, but I don’t know whether it is a typical amount.

My question is, is Platten Gap a consistent dimension from machine to machine? In other words, might a standard Platten Gap on one 9880 be slightly different from another? I print with Photo Rag, which specs say requires a Standard Platten Gap, but given possible inconsistencies between printers, might a Wide Platten Gap be normal or the “standard” for my machine?

Is there something else that could be causing the marks?

Thanks,

Drew Harty


#2

Hi Drew~

I occasionally get these print head scuffs when printing on curled/bowed, or heavyweight paper, such as 308gsm PhotoRag. In this case, I set the platen gap to “Wide”, and in extreme situations will go to “Wider” to get a beautifully clean print.

Best regards and happy printing~ Dana :slight_smile:


#3

Hello Danna,

I am getting the print head scuffs on Photo Rag 188 with custom paper set at standard and Platten Gap set at wide.

Will going to extra wide cause any problems, or does it just mean the Platten Gap distance on my 9880 is somehow off and setting to extra wide is compensating for that?

Right now I am loosing about 25% of my large prints to these head scuffs.

Thanks,

Drew


#4

oh, I thought you were printing on the 308gsm weight… in that case your print head scuffs don’t seem normal with such a thin paper.

What is the humidity in your printing environment? Very high humidity can cause paper to swell
Are the scuffs always in the same area of the paper (1/3 the way in on the right and left sides of the 36" roll)?
Have you tried a different paper, or paper size?
Your new target looks good, was this printed on this same 36" roll, or sheet media?
Does the printer have paper rollers the whole width (it’s not missing any)?

~Dana


#5

You could print a small test with the platen gap at extra wide/widest, to check the print quality, then if the print looks good, hope for the best and make a large print…


#6

Hi Dana,

The target was printed on the same 36" role photo rag paper. I bought 20 roles to get through a print job.

The scuffs typically are in about the same position, but I think the print head scuffing the paper is causing build up on the head which in turn causes more marks elsewhere.

The humidity in my studio is consistent and low.

My test prints are smaller (about 10" high of the role) and periodically get the same marks, though it doesn’t seem quiet as often.

I have set the platen gap to wide, but every time I turn off the printer it resets, which makes me wonder if the platen gap is changing. (I see no difference in print quality looking with a 6x loupe.) I will try entering a wider platen gap using a custom paper and see if it stays when the printer is turned off.

From advice in the service manual, I also checked all the paper suction air holes and foam filters. Some of the holes had a lot of paper dust in them and one foam filter was missing. I cleaned out the wholes and replaced the one foam filter.

I will do some more test print today. It makes for very tense printing not knowing whether marks are going to show up in the last 12 inches of a 30x50 print!

Will you be able to get the custom curve done today?

Thanks, Drew


#7

Hi Drew~

This doesn’t sound normal at all, so I hope your cleaning out the paper vacuum holes and raising the platen gap to Wide solves your problem. I know how maddening it can be when a huge print has a defect, and has to be reprinted…

I made your custom curve this morning, and emailed it to you. Please let me know how things looks with the custom curve, and keep me posted on your platen gap/ head strike issue- I’m curious.

Wishing you positive results for happy printing~ Dana :slight_smile:


#8

Hello Dana,

The custom curve looks good. It’s nice to be printing with all that shadow detail that was dark and flat in the standard K7 curve.

I had one good day of printing with no marks on prints, then they appeared yesterday when running another large print, in the usual areas about 1/3 in from the right and left side of the 36" wide paper as it goes through the printer.

I tried something after removing a head scuffed print front the 9880 that resulted in the attached image. With the machine on, I entered the replace cutter command, unlocked the paper hold dow, and slowly pulled the paper down a couple of inches. You can see on the print the two vertical smudges about the width of the print head frame and the blob that probably caused the mark on the print.

I would guess the inks builds up over of day of printing then eventually marks the paper.

Do you have any idea what could cause the ink to build up in this way; or, to think about it another way, why the wiper blade is not removing the ink? The Epson tech I bought the printer from said he put in a new pump cap station. At the end of a day’s printing, I always see a build up of ink on the bottom 1/8" of the wiper blade with the rest of the blade completely ink free.

I am running a 30x50 print now, and it is just nervous time not knowing if marks will appear!

Drew


#9

The problem with the black marks on prints has been solved. I was going to take the 9880 back to the Epson service tech I bought it from for service, and he suggested i drop the pump cap station and flushing box and check the print head frame for any ink build up.

There was a good amount of accumulated ink/dust or lint build up on the slanted sides of the print head frame and top. I throughly cleaned the print head frame and have not had any black marks since.

Thanks for your help,

Drew


#10

Hi Drew~

I’m glad your printer problem is solved after cleaning, and the custom curve is giving you beautiful results.

Best regards and happy printing~ Dana :slight_smile: