C-6501 print defect

[selmila]

Hi, i have attached 2 files that shows the defect print which is take in KM C-6501. I have replaced the colour registration unit,Lazer unit (M,Y,K) but still the print defect shows up.It is really bad in some part of the text print that is take on 300gsm 13-19 size which i have attached and the defect shows in the first and middle row of the print but the defect is not showing up on plain and 170gsm.

The first time i have replace the Lazer unit and done with the procedures is showed improvement but again gone to bad after few days, it happened the same with the colour registration unit.I have done colour registration adjustment Auto and manual.

[Mick01]

Re: C-6501 print defect

Hi,
You mentioned that the colour registration is shifting using 300gsm stock. Does the colour registration go off worse from the middle to the trailing edge? Paper thickness and grain direction have a huge bearing on image registration. Specs for 300gsm should be no greater than 300 micron and short grain.

[selmila]

Re: C-6501 print defect

Hi,You mentioned that the colour registration is shifting using 300gsm stock. Does the colour registration go off worse from the middle to the trailing edge? Paper thickness and grain direction have a huge bearing on image registration. Specs for 300gsm should be no greater than 300 micron and short grain.

Hi,Yes the colour registration go off worse from the middle to the trailing edge and some times it is ok.

[Mick01]

Re: C-6501 print defect

Sounds like that the Paper is out of specs for the machine unfortunately. The issue is that the paper is too thick and stiff which is causing speed issue with the registration unit and transfer unit.

[selmila]

Re: C-6501 print defect

Sounds like that the Paper is out of specs for the machine unfortunately. The issue is that the paper is too thick and stiff which is causing speed issue with the registration unit and transfer unit.

well i have cross checked the paper in another machine and the print is good.

[Mick01]

Re: C-6501 print defect

If the paper shows no issues on another machine then your issue is probably Fusing unit related. If possible try another fusing unit in the machine (pay careful attention to the fusing entrance sensor actuator). Try doing a Manual colour registration adjustment with the paper that is causing the registration problems to see if it sets up ok.
One thing you mentioned is that you replaced the Laser units. Ensure that the replaced units are for C6501 (not C6500). They look almost identical but they are different and will give colour registration problems if fitted.
Hope this helps