Xerox 800 - curved mark on center tail of sheet and color loss at tail of sheet

[Guest]

Hi all.

I have a Xerox 800 ColorPress

I am running a short sheet 11 x 15 (12 point - 225 gsm). At the center tail of the sheet I am getting a curved mark. It doesn't seem matter which side of the sheet prints first and it's always in the same position at the tail of the sheet. I removed the curved shield over the IBT belt and it stops the mark but the 2nd BTB belt shreads itself. So the sheet is definately bumping that shield, but how do you solve it?

Also, I am losing color at the very tail end of my image (within the last 1/2" of the sheet). I tried to move around the value of the 2nd side bias in the advanced paper properties which helps but doesn't cure the issue.

I also tried tricking the machine by telling it my paper was thicker than it actually is. The problem doesn't go away and I start to lose image quality elsewhere.

Any ideas?

Thanks for any assistance.

 

[DYP]

In you stock library do you have a setting for Transfer output adjustment for trail edge. If so reduce it.

 

[Guest]

thanks for the reply. The only settings I see related in the stock properties are
"2nd Bias Transfer Roll" (Side 1 & Side 2) and the "Aligner Roll Pressure"

If this is in the ColorPress 800 Stock properties, I wouldn't know where to find it. Where is it for you?

Thanks!

 

[DYP]

Not sure about the 800 but the Versant has that setting.

 

[Stochastic]

Resolution for "Trail Edge Flick"

Resolution for "Trail Edge Flick"

Hi all.

I have a Xerox 800 ColorPress

I am running a short sheet 11 x 15 (12 point - 225 gsm). At the center tail of the sheet I am getting a curved mark. It doesn't seem matter which side of the sheet prints first and it's always in the same position at the tail of the sheet. I removed the curved shield over the IBT belt and it stops the mark but the 2nd BTB belt shreads itself. So the sheet is definately bumping that shield, but how do you solve it?

Also, I am losing color at the very tail end of my image (within the last 1/2" of the sheet). I tried to move around the value of the 2nd side bias in the advanced paper properties which helps but doesn't cure the issue.

I also tried tricking the machine by telling it my paper was thicker than it actually is. The problem doesn't go away and I start to lose image quality elsewhere.

Any ideas?

Thanks for any assistance.

Hi, please contact your service engineer for fixing what is known on these machines as "Trail Edge Flick" there is a baffle that needs to be removed under the IBT assembly which will prevent this from happening. you may experience impact banding but your tech will explain this.
You will be experiencing this on heavy stocks.

Once the baffle is corrected then your bias adjustments can be fine tuned.

You will require a service engineer for this issue and the issue has been put out as a service bulletin in 2013. If your tech doesn't know, then request another more experienced engineer.

 

[Guest]

I think you nailed my issue.

It seems like you may have dealt with this issue in the past.

We are on Time and Materials with Xerox. Do you know about how long a task like this should take a tech to perform? A few minutes? A couple of hours?

Thanks for the direction.

 

[Guest]

This baffle has now been removed and having another problem. Not sure if it's related? The BTB unit belt wants to wander over to the drive side of the press. One of them shredded itself up. I put another one in and it hasn't shredded yet but the belt definitely wants to ride right up against the inside of the BTB housing on the drive side. I never noticed where this belt rode before. Is that normal for the belt not to track into the center of the unit? I don't see how it could be related to that baffle as it doesn't look like they touch.

Any thoughts?

 

[Craig]

We use to have to shim the bushing on the 8080 btb. Have not had to do this on the 1000 yet.

 

[gig0]

you are getting the exact same issues we see on our KM 1070. Always the tail edge of heavier stock. There is a setting that helps minimize it. I can't recall the exact menu setting unless I'm in front of the machine but I'll check Monday morning.

 

[gig0]

It's the 2nd transfer pressure setting on the KM, if that helps at all. It can be lowered. It doesn't really cure the problem with the heavy stocks but makes it less of a factor.

 

[arossetti]

This baffle has now been removed and having another problem. Not sure if it's related? The BTB unit belt wants to wander over to the drive side of the press. One of them shredded itself up. I put another one in and it hasn't shredded yet but the belt definitely wants to ride right up against the inside of the BTB housing on the drive side. I never noticed where this belt rode before. Is that normal for the belt not to track into the center of the unit? I don't see how it could be related to that baffle as it doesn't look like they touch.

Any thoughts?

Damn wish I could help on this. We had the same issue, went through a new 2nd transfer every 60k images. Service was able to fix it but I forget what had to happen. Should be a known issue with a technical bulletin if you get service involved.

 

[Craig]

They just ordered a heavy stock baffle for the ITB, when we pulled of the other baffle the curve matched perfectly. The tech said the heavy baffle is shorter and thus eliminates the issue.

 

[Guest]

I was able to match the mark up to the baffle at the bottom of the ibt belt. My tech said to just run without it. Unfortunately about 300 sheets after I took it off, my btb belt shredded itself. However, I don't see where the btb and this baffle even come into contact. Maybe just a coincidence that the btb shredded near the same time??? I know the baffle helps to keep the belt up when you are pushing the ibt belt drawer back into the machine. Other than that, what is the purpose of the baffle?

 

[Guest]

Does anybody happen to have a photo of the heavy stock baffle for the colorpress?
I am going to order one but just curious what they look like. My tech told me the part number is 604K68270