P20000 marks in middle large rolls,

[narikin]

My P20000 has started marking each large print at the beginning of the image, right in the middle.
I have the extended warranty, but would like to be up and working sooner - any ideas?

It's right in the middle of a 60" roll, like something is lifting the paper at that point and making a series of scuffs over 2 to 3" then stops for rest of print. Seems to only happen with the heavier expensive paper (Platine) not EPL 260. Paper was set to Baryta, which is pretty thick, so...?

[I.T. Supplies]

You may want to check your vacuum settings on that type of paper.  Sometimes the vacuum isn't as high as needed and the rollers make the marks on the paper before it gets ink applied and shows the marks after inks is applied.

If it's not the vacuum issue or rollers, than probably paper.  The coating can also be a problem where it isn't applied to the roll properly and "may" cause this issue as well.

[narikin]

You may want to check your vacuum settings on that type of paper.  Sometimes the vacuum isn't as high as needed and the rollers make the marks on the paper before it gets ink applied and shows the marks after inks is applied.

If it's not the vacuum issue or rollers, than probably paper.  The coating can also be a problem where it isn't applied to the roll properly and "may" cause this issue as well.

Thanks. It's happening in the same place every (60x80") print off a 60" roll, so I don't think it's the coating. I'll try upping the Vacuum, but it's a new problem, 2 years into running this printer, so makes me think something has changed or gone out of alignment. Printer paper setting is 'Baryta' (there isn't a 'Platine' setting on the printer firmware, though Epson sell a Platine. It is set to Legacy Platine in the Driver though - they do give you the option there!)

Kind of looks like a head strike, or... a head 'smoosh'  to me, so I'll investigate. A problem is at $350/roll of Platine, you don't want to troubleshoot too much on the good stuff, BUT it only happens on that, not the proofing papers. Sigh.

[deanwork]

I don’t have your printer but I’ve seen this throughout the years on all brands of large format printers and it has always been the result of paper curl and head strikes. I’ve seen it on various “baryta” media but only once on Platine toward the end of the roll where it curls the most. If I were in your shoes I would try setting the platen gap setting on the printer menu to a wider setting. If that didn’t work I would call Epson and tell them it is the Legacy Platine and see if they have had complaints with head strikes on that paper. Since Platine is cotton, not alpha cellulose it doesn’t curl as much and it does flatten easier. I had situations where toward the end of a roll I had to cut off sheets and flatten them under foamcor with weights on top overnight I realize if you are doing really big prints that might not be practical.

John


quote author=narikin link=topic=128585.msg1089798#msg1089798 date=1547581815]
Thanks. It's happening in the same place every (60x80") print off a 60" roll, so I don't think it's the coating. I'll try upping the Vacuum, but it's a new problem, 2 years into running this printer, so makes me think something has changed or gone out of alignment. Printer paper setting is 'Baryta' (there isn't a 'Platine' setting on the printer firmware, though Epson sell a Platine. It is set to Legacy Platine in the Driver though - they do give you the option there!)

Kind of looks like a head strike, or... a head 'smoosh'  to me, so I'll investigate. A problem is at $350/roll of Platine, you don't want to troubleshoot too much on the good stuff, BUT it only happens on that, not the proofing papers. Sigh.
[/quote]

[narikin]

I don’t have your printer but I’ve seen this throughout the years on all brands of large format printers and it has always been the result of paper curl and head strikes. I’ve seen it on various “baryta” media but only once on Platine toward the end of the roll where it curls the most. If I were in your shoes I would try setting the platen gap setting on the printer menu to a wider setting. If that didn’t work I would call Epson and tell them it is the Legacy Platine and see if they have had complaints with head strikes on that paper. Since Platine is cotton, not alpha cellulose it doesn’t curl as much and it does flatten easier. I had situations where toward the end of a roll I had to cut off sheets and flatten them under foamcor with weights on top overnight I realize if you are doing really big prints that might not be practical.

Thanks John,

I too suspect headstrike by Platen Gap  issues. Yes this was towards the end of the roll, but, it repeated in the exact same place, even when the paper was not cut - so there was a 'tongue' of over 90" of roll paper already out of the printer (I  trim down XL rolls of prints manually later) . And as you say, Platine is all cotton, and does not have the fierce curl of Baryta, though it does have some especially towards the end of roll. (this was in the last 12 ft of a 50ft roll). What is frustrating is seeing it repeat in the same spot on each print, and ruin $$ of output.

I'll put a new 60" Platine roll in and see what happens at the beginning of that, later today.

Best.

[narikin]

Well, a fresh roll stopped the marking, prints came out fine. But... this didn't used to happen. so it's a mystery.

I'll increase the default thickness and platen gap for all future prints on this paper (is there anywhere to find paper thickness, e.g. Canson Platine (- is it 0.4 or 0.5 mm? I don't own a micrometer!)

The test will be if it happens again in the last 25% of this roll or not. Can't loose 1/4 of every roll.

[deanwork]

I’ll tell what the deal is. The longer the rolls have been on the shelf the more they maintain that tight curl at the end of the roll. Of course you never know how old the roll is until you get into it. So my standard policy for the last 15 years has been to use the last 4 or 5 feet or so of rolls, both matte and fiber gloss, as cut down sheets. I flatten them in a dry mount press for smaller 20x24 or less sheets or flatten between sheets of foamcor for larger sheet printing. It’s not fun with 60 inch rolls but that is the way it is.
What you don’t want man is head strikes because that can damage your heads so you just have to sacrifice some paper to sheets at the end to avoid that and all the headaches that come with it. You also see some pressure marks on the roll at the very end that can only be removed with a dry mount press in many cases. And this is not a characteristic of Canson media, Hahnemuhle is just as bad or worse. Baryta is far worse. 


quote author=narikin link=topic=128585.msg1090115#msg1090115 date=1547742317]
Well, a fresh roll stopped the marking, prints came out fine. But... this didn't used to happen. so it's a mystery.

I'll increase the default thickness and platen gap for all future prints on this paper (is there anywhere to find paper thickness, e.g. Canson Platine (- is it 0.4 or 0.5 mm? I don't own a micrometer!)

The test will be if it happens again in the last 25% of this roll or not. Can't loose 1/4 of every roll.
[/quote]

[narikin]

Yeah, I like to avoid head strikes, obviously.

I've had none on the P20000 till this. Oh yeah, except a 13x19" sheet of Harman-by-Hahnnemuhle Baryta I put in there as an emergency when my 3880 was needing ink, and that shredded itself in the P20000. I never found all the pieces! Not putting 'small' cut sheets in there again! Certainly not curly Baryta types like that!

I did read, a lifetime ago, someone saying there are ways to deliberately destroy your head under warranty and get a fresh one!
No idea what they were doing, maybe endless power cleans, but seems very dodgy behavior.