Konica c6500 Color Registration Problems

[sweep]

Hi, New to this forum, 1st time in any forum actually so please bear with me.
I have a problem with registration of all the colours on my konica c-7000
The black being the worse at approx 2mm out. cyan, magenta and yellow
all out with the black and approx 1mm with each other.
I have replaced the registration unit with one from another press which worked well on my other press.
I also swapped the IBT unit from my other press which also worked fine on my other press.
Any feedback would be much appreciated

[Desert Rat]

Sweep,
As mentioned before, I find most registration problems are related to copy quality. Make sure your PM numbers are low.
You may need to change the developer. I have seen them get under concentrated and produce a print with mottle and
you can feel the developer mix on the page. Whatever color that is, needs more toner. You can manually add toner to that
color. Then run the toner init. program so it will keep up with itself.
Don't mess with the mechanical adjustment for the laser lens.

Keep up posted

DR

[Bernard]

Hello,

We've suddenly encountered a problem with our Konica c6500 unit and have been struggling to fix it but with no success. As to the attached image, the colors are completely out of registration. The odd part is how they seem to be different depending on which part of the print they are in. It appears the colors are out of alignment horizontally but not vertically.

To let you know of the steps we've taken to fix it:

We have done numerous auto color registration adjustments
We have done numerous auto gamma adjustments
We have swapped out the transfer belt assembly with 3 other working assembly units
The color registration unit was swapped out
We have tried doing a calibration through the Command Workstation

All proved unsuccessful.

It isn't just this paper either. Our uncoated stock we normally calibrate on with Gamma Offset has the colors out of registration on the gradient scale, and the scan for calibration through the Command Workstation shows the black bars off center with the Cyan patches. This is a first for us.

We're starting to see it on another unit too where the colors are going out of alignment left to right, so we are concerned that unit could be on its way to this.
Please, if anyone knows what is likely happening and the answer to this problem, let me know.

Is it throwing a code? I would checked your toner level or depleted developer in one of the colors. Especially the yellow. It'll still pass calibrations sometimes even though color is depleted.

[mircea]

try to jam one page before it enterses fusing unit.
Take a look at that page and at how the image looks on transfer belt.
I think you still got a problem with color registration unit if it looks bad on transfer belt too.
Does that page look all the same? or it only does that problem repeats itself 1-2 times/page?
try to take a look at transfer roller motor too...Had a printer and the motor's metal teeths were bad and it was jumping 2-3 steps/page and was doing something similar to your problem.
If nothing works go in service mode and check the registration color/gamma sensors values and see if you find anything abnormal.

best of luck