[CQ] C6501-Banding at trailing edge on 250gsm

[levino]

Hai All, Happy New Year

My 6501 with 700000 clicks is now giving the banding at trailing edge above 250gsm.I replaced transfer rollers upper and lower with no result.Any body can put some ideas.

Thanx in advance

[rangertech]

Re: C6501-Banding at trailing edge on 250gsm

i think the problem in fusing unit..

[Gaffers01]

Re: C6501-Banding at trailing edge on 250gsm

Looks like a transfer belt problem.
What's the paper size of your sample?

[levino]

Re: C6501-Banding at trailing edge on 250gsm

Hai,
My papre size is 11 X 17.I had replaced the fuser unit and transfer belt with 2nd transfer roller upper and 2nd transfer roller lower,still problem exists.

LEVI

[mrwho]

Re: C6501-Banding at trailing edge on 250gsm

If it happens always at the same place of the paper, try fiddling with the paper settings, namely the transfer values. There should be plenty of threads about it, try to search for them.

[prakashshetty_thane]

Re: C6501-Banding at trailing edge on 250gsm


Have u checked the actuator (indicated by No 3 in the above diagram)?.
The part code is given below:

A03U730800

Entrance Actuator /A

U can find it in the Fuser unit just where the paper enters the fuser unit.
They tend to break and cause such problems.
If broken replace the actuator.
That will solve the problem.

[eifling]

Re: C6501-Banding at trailing edge on 250gsm

I have seen this problem before but normally its with max spec paper. In the past ive moved the regestration loop to get it off the edge of the sheet. It seemed to be how thicker paper would buckle going into the fuser. I would go -30 on reg loop and it would clear it up. That might be your problem.

[beetle73]

Re: C6501-Banding at trailing edge on 250gsm

Hi there
I've had that problem before! The wrong grain of paper is being used!

[jzheld]

Re: C6501-Banding at trailing edge on 250gsm

is it only for cyan or for anything you print, I would check gears in the fuser, and registration roller

[axel]

Re: C6501-Banding at trailing edge on 250gsm

is it only for cyan or for anything you print, I would check gears in the fuser, and registration roller

i belive the problem is the shape of the entrance actuator in the fuser module, becauce the sensor of this actuator is working not only as a jam sensor but also as a timing sensor.When we use very thick paper, the actuator could not be activate in the right time with the lead and trail edge of the paper.You can see that if you try to print or copy, on very thick paper, with the front door open.The thick papers are not flexible,this is the real problem.

Best Regards.

[BVulgaris]

Re: C6501-Banding at trailing edge on 250gsm

mrwho mentioned in this post to fiddle with the paper settings, and that there may be threads somewhere discussing the values for this.

I currently have found no description of the some of the paper settings- process adjustments. The FD&CD mag and other machine and paper settings are easy enough to figure out, however I have not found any description of the settings in the process adjustments of the paper settings.

Examples:
Separation AC (Front/Back)
Separation DC (Front/Back)
Compulsion off upheater
2nd trans pressure
CMP Down

I also am looking for some explanation on the voltage controls but that might be for another post.

and yes, i am getting an issue similar to this one on greyscale print on 256gsm. I have found temporary solution in setting glossy as checked in the RIP, or anything that increases the black densities. But i dont think that trick will work in every instance.

[eifling]

Re: C6501-Banding at trailing edge on 250gsm

I've had this problem several times when dealing with thicker paper and as i said i could normally get the band to go away by going -25 to -40 on the registration loop setting. Some one else said its a fuser problem, its a transfer problem but as the op said, he replaced all that and still had the same results. For me all signs point to how the paper curves against the lower transfer roller. I could be wrong but I have always been able to get the trail edge band to go away through the settings. Some stock just seems to do this.

As far as greyscale banding, ive had luck with going to a lower gsm then what the paper is and turning the temps up a bit. Also switching from dot to line helped.