C1060 interesting artifact

[blackcat4866]

The enduser shows me an artifact, let's call it a "smudge", towards the trail edge ONLY when printing onto 271gsm media. The images are nearly 350% fill (almost solid black edge to edge). The artifact is 6.5mm wide and 32mm long measured from the trailing edge. It's hard to see on the 350%fill prints, but I lucked out getting a perfect example on the Fiery start up pages. Yes it's got the correct media type set, but there is pretty significant curl even on simplex images.

Artifact.JPG

So I found two things:
First I removed the rubber seal on the registration guide. It had a wave that stuck up at the center.
Second I adjusted the paper curl to +1.5, which flattened it right out.

What I think was happening was when the heavy media gets fused it's curling the paper and the trail edge flips. I think that rubber seal was skimming toner off of the primary transfer belt, and depositing it on the trail edge when it flipped.

Primary Transfer Belt Seal.jpg

I thought it was worth posting about. =^..^=

[kenpio]

Re: C1060 interesting artifact

Yes I have seen this, C6500 and up. That is one of the first things that I take off. I know that it serve a purpose for something, make smudges I guess.

Thanks
KEN

[OverKnight]

Re: C1060 interesting artifact

I'm adding to this thread because I have something similar coming from this area.

When running sheet with an image of flooded black and gradients (see sample image), there is a ripple forming down the sheet. This doesn't seem to repeat itself on jobs with major CMY color.

IMG_2972_Circled_Opt.jpgIMG_2973_Full_Opt.jpgIMG_2974_Buckled_Image.jpg

As you can see in the sample image, the weakness starts on the side but will intensify and skip into the center and then become very pronounced. This will occur only if the run is long enough to allow for the timing of the issue, run for 5-6 sheets with the issue and then return back to normal. Again, if the run is long enough, the cycle will then repeat itself.

In both sample images, the images are pure black not a build and the Pro Lightning is the worse case scenario.

My concern is a diagonal stress from the stock entering into the transfer area causing a ripple to form and then going into the fuser. This is a label stock and set at 217-256 g/m²which is close to max for this C1060.

My guess is the registration roller is pulling the stock diagonally and at the image transfer point buckling a bit causing the image weakness in black.

Appreciate any ideas. Thanks!

[wjurls]

Re: C1060 interesting artifact

There was just a recent posting about this on the Konica Tech Training "Jam" forum. Seems that black mylar wreaks all kinds of havoc.

[OverKnight]

Re: C1060 interesting artifact

wjuris,

I just added a third image which I will repeat here to clarify my description:
IMG_2974_Buckled_Image.jpg

Do you have a link to that thread you mentioned and what do you mean "black mylar"?

Thanks!

[allan]

Re: C1060 interesting artifact

wjuris,

I just added a third image which I will repeat here to clarify my description:
[ATTACH=CONFIG]48205[/ATTACH]

Do you have a link to that thread you mentioned and what do you mean "black mylar"?

Thanks!

That looks like voids on the mag roller. Could be contamination in the tank or low developer level.

[OverKnight]

Re: C1060 interesting artifact

That looks like voids on the mag roller. Could be contamination in the tank or low developer level.

I would agree with you, but the developer is at 58% and the problem is not a constant. I would expect a problem with a roller or developer to be constant while this issue starts and stops in intervals.

The one consumable that is past it's life is the coronas. I have a corona set coming in and I know that this issue will disappear, however I want to ensure that it doesn't signify something else more pressing.

Thanks!

[blackcat4866]

Re: C1060 interesting artifact

That looks like voids on the mag roller. Could be contamination in the tank or low developer level.

+1. allan is right. And we've had plenty of cases where the developer craps out as early as 30% of life. I haven't been able to pin it down to a specific developing unit, because changing that black developer will last 100% to 120% in the same old developing unit. I believe it's just a bad batch of developer.
=^..^=

[wjurls]

Re: C1060 interesting artifact

wjuris,

I just added a third image which I will repeat here to clarify my description:
[ATTACH=CONFIG]48205[/ATTACH]

Do you have a link to that thread you mentioned and what do you mean "black mylar"?

Thanks!

The black mylar is the one on the second transfer unit guide just before the roller.

"Jam" is an private forum from KM technical training so it can't be linked to.

What you show here is what Konica refers to as "developer screw marks" Your black developer is depleted and you are seeing the effect from the stirring auger in the developing unit.