Pinch roller track marks in print

[Colin]

I'm printing some big banners (13 ox JetFlex gloss). The lettering which is 85% black and a graphic which is 90% black (on 100% black flooded background) is getting track marks from the pinch rollers. They don't appear on any other parts of the print.

The print is obviously not returning under the rollers, so why is this happening, and is there a fix?

 

[Salmoneye]

Mine usually goes away after the first foot or so but if it is a heavy solid most guys just run the outside two rollers. Make sure that you roll out your material so it is loose on the feed side or it will buckle as well.

 

[Colin]

These banners are 4' x 20-30 feet long, and because of some other print issue, I'm having to run the head-height at "low", so I feel that I need the 3 inside rollers.

I'm trying to figure out why the heck it would leave marks on the 85 & 90% black, but nowhere else on the varied print.

 

[HulkSmash]

most of the time they come out in a few hours.

no big deal.

 

[Colin]

most of the time they come out in a few hours.

no big deal.

I hope you're right, they're significantly darker.

 

[2B]

we have seen this happen,

once the ink dries you are good to go

 

[Colin]

It's been over 24 hours and the track marks haven't diminished at all.

 

[Fatboy]

Colin can you post a pic?

 

[Colin]

Here's an image. I was wondering how & why these track marks would disappear.


.

 

[Jack Knight1979]

That is odd. I at times need to clean my rollers with alcohol. Are your rollers clean?

 

[Colin]

Are your rollers clean?

Yes. And again, this didn't occur on any other part of the varied print.

Who ever thought large format printing could be so much fun?

 

[LenR]

I'll bet it's something in the document. I see odd stuff this in Illustrator files frequently.

 

[Colin]

I'd bet money against that. They're just basic vectors filled with 85% K.

Could it be that the pressure associated with the inner rollers is too high?

 

[Jack Knight1979]

Wide format printing is a constant struggle. I find that printing rarely goes as it should. Feed will go bad, roller marks, head strikes, bad material, bad ink, bad head, blown fuse, bad board, yadda-yadda-yadda. hahah

it never ends.

 

[ZsVinylInc]

I use to have this when printing banners. It didn't matter what brand it was. I was running a Roland. The only thing I found to do is just use the outside two pinch rollers.

 

[ICeMAnAbk]

Hm. Try cleaning a section of banner before you run it though. Might be something on it when it comes from the factory. Worth a shot to try.

 

[tomence]

I use to have this when printing banners. It didn't matter what brand it was. I was running a Roland. The only thing I found to do is just use the outside two pinch rollers.

This is what i would do too.

 

[sfr table hockey]

Here is my take on the track lines.

Roland black ink seems to be heavier density (think that is how to say it) as comared to 3rd party ink it lays black way heavier. If a profile is not set up to reduce the black volume, then the chance of overspray is greater. Also when static is involved it tends to show more when black fill or black text is being used compared to other colors. I think the feed rollers create a bit more of a static charge as they roll over the media and when the middle rollers are being used they tend to gather some of the overspray and then the rollers track the black onto the media.

So if you were to clean the rollers right after this happens you may find some black on them. Lowering the heads seems to help because there is less distance for the static or overspray to take effect.

Just as a test if you lower the black ink limit by about 20% and re print that section of the print and see if the same thing happens. The black will be off in color but it might not cause the overspray onto the rollers. If this fixes the problem you may want to play with the black ink limit a bit till it no longer happens but yet still gives a good black coverage.

 

[Colin]

^^^Interesting hypothesis, however the rollers remained clean even after printing the equivalent of a full roll of 54" banner material flooded with black ink. (Not exaggerating - I've been working full throttle 18+ hrs a day for days now).

The head height was also set to low to mitigate a separate issue I'm having with the K channel.

 

[FishnSigns]

Try printing the same file on a different material to see if the lines are still there. If they are, you can isolate the printer from the media. We have had challenges with banner material in the past leaving pinch roller marks and it was some oil on the banner material. If that is the case, clean your pinch rollers with iso alcohol and grab a fresh roll of media. Worth a shot.