Fine vertical scratches

[petercorb]

I use a 9900 with most of my work on Matte papers. I recently had a rather big job which involved using Epson Traditional Photo Paper (PK) I think it is called Exhibition Fibre in the US - customer specific request. The printing went well but the customer brought back the work and complained about very fine vertical scratches running down through the entire prints (95cm long side). It takes the right light and viewing angle to see them but they are definitely there. I ran some more tests with different platen and paper settings but it is still there. I live in Cape Town right on the coast and when the wind blows sand gets everywhere. I am wondering if very fine sand particles have gotten embedded into the rubber transport rollers. The paper transport action is one of "stop//start" as the paper progresses and perhaps these particles are causing this scratching with this "jerking action". It does not happen on Matte, I presume because the surface is not as fragile. Before I approach Epson I would like to know if anyone has had a similar experience, there is a thread here a long time ago with Ilford but seems inconclusive http://forum.luminous-landscape.com/index.php?topic=39206. Also I may try cleaning these white rollers very gently - any ideas about what to use?

[silviapestalozzi]

We used to run a lot of Innova papers. Their baryta types showed the same fine vertical scratches you discribe, they were on brand new rolls. And some users say the Epson Traditional is identical paper from the same source. Maybe you have an older batch. At least the new Innova glossy coatings don't show those scratches any more and they are a lot more robust and scratch resistant. Go and check the unprinted paper very closely with light coming from an angle, wouldn't be surprised if they are already there.

[jferrari]

Those lines may not be scratches. Try a head alignment. Or, if you don't want to do that, turn off high speed (bi-directional) printing. Hope this helps.     - Jim

[Paul2660]

My 9900 will often scratch a glossy paper. Try to use Epson PGPP 250 weight or MoB Lasal both RC papers.  I don't think your issue is sand or grit but it won't hurt to try and clean the rollers.

I have also seen the faint scratches on Exhibition fiber however not running the length of the print just intermittent.

I switched to Canson Platine and Byarta got fiber based prints. Both of which print on my 9900 without scratches.

Paul

[petercorb]

After some more thought about this issue I don't think its sand or grit either. I did some printing with Epson Prem Luster 260 and there is no sign of scratches, I have a feeling it exists already in the paper. I don't use much photo papers but had some offcuts from a much earlier roll of the same and I noticed a slight difference in base color. You may be right Silvia, it could be from way back. the problem here in South africa is that there is not the great choices you guys have in US or Europe, we have Hahn, Epson, Inova with Epson dominating. Anyhow the roll and a print will go back to the Epson agent and see what they have to say.

[Wayne Fox]

I ran some more tests with different platen and paper settings but it is still there.

What is your paper thickness setting?  Platen gap is only part of the equation, paper thickness moves the entire head assembly and transport system allowing a slightly wider paper path.

Are they rolls or sheets?  Rolls of Exhibition Fiber and similar papers are very difficult to get through any printer perfectly.  Humidity can help.

[petercorb]

i use 8 papers (2 PK infrequently)

I have them all set in the Custom Paper menu; some are the same setting, however it is a good reminder of what I am using and prompts me to check the settings at times using the Epson control system for this function i.e. let the printer with the appropriate paper set the "paper thickness" ( assuming you can read the alignment correctly).

I have used this since my 7600, 7900, & now 9900 days and still seems to work for these papers:
150gsm Platen Gap - Narrow
190gsm     "           - Std.
260gsm     "           - Wide
320gsm     "           - Wider
500gsm     "           - Widest

So for Epson exhibition Fibre (AKA Traditional Photo Paper) 325gsm my Custom Paper setting has always been "Wider" and the printer tells me - looking at the vertical line alignment that the paper thickness should be (3) 0.1mm - same as the setting in the Print Menu.

Then there is another Paper Thickness setting in the menu Head Alignment>Paper Thickness. This ranges from 3mm - 90mm (I think) and has always been set on 12mm.

So what did I try?

Wider Platen and Narrow Platen.
Paper thickness in the custom settings.
I did not move the setting in Head Alignment other than run a alignment check.

Nomenclature:
Epson Technical Spec for Papers: 305gsm, 19ml for Cold Press Bright (an example) - what is this?
Paper Thickness> Alignment Menu 12mm (an example) - what is this?
Paper Thickness in the print menu and Custom Paper settings (3) 0.1m - what is this?

Are these actual "metric" measurements and what do they relate to?

The manual is so obtuse that the paper thickness in the Alignment Menu is not mentioned.

I still have the problem and am now convinced its faulty paper.

[Wayne Fox]

I wouldn’t mess with the paper thickness in the Alignment menu.

Here are the specs for exhibition Fiber

325 g/m2 ... grams per square meter.  This is the “weight” of the paper and offers an idea of how “heavy” or “thick” the paper may feel in hand. Sometimes it is listed as gsm,  grams square meter.

13 mil ... (12 mil for rolls). The actual thickness of the paper.  To get a useable number in the printer driver this needs to be converted to mm, 13 mil is equal to .3306 mm, 12 mil is 3.048 mm.

(I assume in your example you meant 19 mil and not 19 ml unless perhaps ml is used on other languages in place of mil, to me ml means milliliters which wouldn’t make any sense.  A 19 mil paper is  .4806mm so I would use a setting of 5 for the thickness).

The default of 3 in the printer setup is close for EEF,  but personally I use 4.  Just found I have less issue with surface defects.

Platen gap is the space for the transport mechanism, so changing the paper thickness moves the entire transport assembly(head and platen).  Platen gap allows more room through the transport mechanism but does not move the head. After getting the width set correctly, forcing the platen to a wider setting can help with roll papers that tend to curl and contact various surfaces when moving through the printer.

Some other things that can help with issues like this is a little more suction to help keep the paper flatter (although this may also cause other issues) and indeed slowing the printer down by using unidirectional and even allowing a slight drying time per head pass can help, allowing the ink to set and dry before it contacts the offending rollers in the printer.

Finally going through the printer and making sure there isn’t any buildup on any of the surfaces might reveal some issues.  It doesn’t take much to scratch some of these papers.

Pretty easy to find out if it is the paper, you should be able to see the scratches before they it goes through the printer.  They will be hard to see but should be there.

[petercorb]

As I thought, it was the paper.

You could not see the scratches as they were very very fine, and only showed up when ink applied and seen at an acute angle.

In fact I did not see it, my customer picked it up.

Also I noticed that particular roll was made in he US and had a completely different label and box, the new one was made in Holland.

I got a replacement from Epson and it's perfect, with my usual settings.

Interesting, I forgot Mil, is a purely American term for thou: 1/1000th of an inch.

Then we have mm which is Metric.

And of course inches - so much for standardisation  (spelt with an "s")

As I said I did not touch the Head Alignment> Platen Gap but here again the term is repeated but no explanation anywhere as to what it does.

Anyone got any ideas?

Anyway thanks for your input Wayne.

[Ernst Dinkla]

Also I noticed that particular roll was made in he US and had a completely different label and box, the new one was made in Holland.

I guess converting from jumbo rolls + packaging has been done in Holland. I'm not aware of any (inkjet) coating facility in the Netherlands for that kind of paper.


Met vriendelijke groet, Ernst

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December 2014 update, 700+ inkjet media white spectral plots

[Stan Prevost]

I was getting fine scratches on Breathing Color Vibrance Baryta, as well as another issue or two.  After experimentation, I settled on determining paper thickness setting by measuring paper thickness and setting it to measured thickness in inches, converting to mm, and changing that to tenths of mm, taking any fractional part up to next tenth mm.  I set the platen gap to auto.  All my problems went away, and I have had no recurrence of any similar problems on any paper.

Other than Wayne Fox's explanation earlier in this thread, I have found no information on exactly what those settings do, and what "Auto" does.  I figured the printer (or driver) must be using the paper thickness setting to determine the platen gap setting.

Stan