Pinch Wheel Lines!?!?!

[ABHDesigns]

Mutoh Valuejet 1604 with 13oz Hurculite banner material.
I get lines in my print or rows right under the pinch wheels??!!
Does anyone else have this happen?? And do you know how I can fix it??
It has only happened with the bantex...so far. And seems to happen...and then not happen.?? As with everything with this machine...it is drving me to drink

 

[bob]

When you print the carriage/heads tend to put a little black ink on the pinch roller that's right at the end of the carriage travel. If you've printed media that's less wide than what you're printing now this tends to leave a line on the media at that point. I just clean the suspect rollers with a little alcohol and all is well.

 

[Rodan68]

I think it just the material. I had the same problem with a roll of 13oz Herculite. The area under the pinch rollers printed darker leaving a striped look on the image. Also the whole image was printing a lot lighter than usual. It's probably a bad roll but for the price (about 2x the competitors) I was expecting better quality control. The only reason I was using it was because it didn't buckle between the pinch rollers like some of the others.

 

[ABHDesigns]

What do you use for banner material? I really like the matte/satin look instead of the gloss. And the 13oz d/s show no scrim.

 

[Rodan68]

Mostly Ultraflex but I'm still have buckling issues on wider rolls. I liked the look and feel of the Herculite but image quality just wasn't that good. I'm open for opinions too. I'm always trying new stuff.

 

[henryp]

Possibly contaminated pressure rollers or the material is sensitive to pressure so when printed on, the area under the feed rollers react differently to the ink than the area where no pressure was applied.

 

[randya]

You might try lower temps, or sometimes higher temps.

Lower pressure setting on the media lever.

Possibly plasticiser migration, if so, you will probably see it on media you print right after.

 

[h82loose]

Have you pulled the rollers out and cleaned them? They accumilate overspray.

 

[Stealth Ryder]

You might try lower temps, or sometimes higher temps.

Lower pressure setting on the media lever.

Possibly plasticiser migration, if so, you will probably see it on media you print right after.

Exactly, provided the rollers are clean of oversparay contamination...

 

[ABHDesigns]

Thanks Everyone. I did a huge clean on the rollers. And that seemed to do the trick. Although, I do think this media is sentive. The temps...was the first thing I had adjusted with no result. And I run all of the media on the low level of pressure.
What is "plasticiser migration" ?

 

[randya]

"plasticiser migration" ?

Plasticizer is what makes PVC flexible.
It can, after a time separate out and 'migrate' to the surface (typically the outerpart of the roll). Ink does not penetrate as well when this happens and can cause printing issues.

It can be absorbed into the printer pinch rollers and then be transfered to the next media.

This is why static cling has such a short shelf life.

 

[ABHDesigns]

Thanks, that was very informative....I have never heard that before. I'm assuming that by cleaning the pinch rollers that it will come off? Or does it destroy them over time?

 

[Salmoneye]

I have had to use just the outside rollers and pre-roll the media off the main roll as it prints. I think that it could be a static issue.

 

[ABHDesigns]

I'm pre-rolling as well but because the roll is so heavy it causes a PF problem. On a Mutoh how do you just use the outside rollers? I did not know that was possible??

 

[ABHDesigns]

SO...I have completed all the above. Had it working great...then 6 banners...and some vinyl printed Great!! Now I'm printing banners again. And It is happening again. RE-cleaned...and nothing. HELP!! I need to know is there another solution. Or do I just need to change material? What banner material do you run? (needs to be smooth with no scrim)

 

[Salmoneye]

The two wheel option is on my Roland, sorry. I used to think that it was because of the pressure that had been applied made that area more or less receptive to ink but I think that it might be static. What is your static like? Taken any precautions to mitigate it? I use ultraflex and the prob is come and go as well.

 

[randya]

SO...I have completed all the above. Had it working great...then 6 banners...and some vinyl printed Great!! Now I'm printing banners again. And It is happening again. RE-cleaned...and nothing. HELP!! I need to know is there another solution. Or do I just need to change material? What banner material do you run? (needs to be smooth with no scrim)

I have had very good results with Herculite banner.
Could it be your vinyl?