Yellow and Magenta Images out of position

[Leo Gasson]

We have installed a QMDI press classic second hand.
We send our first job to the press. We check the CMYK images in the press monitor and all four images appear in the right position.
After burning the image in the plate:
The black and cyan images on the plates are in the correct position.
The magenta image on the plate is out of position 8 cms UP
The yellow image on the plate is out of position 10 cms DOWN.
We have tried four more times with other print jobs and the result are the same.

Can somebody help me to resolve this problem ?
Thanks

 

[jan]

Hi Leo,
first of all check if you didn't interchaged two connectors on the backplane, comming from two encodeurs of the plate cylinder in M & Y.
It could be easy explanation for this issue. If not you will have to change some parameters.
Jan

 

[Leo Gasson]

Hi Jan,

I have verified the positions of the conectors of the Y and M on the back plane and both are Ok.
Could you help me to know what parameters need to be changed and how make those changes.
Thanks. lgasson@hotmail.com

 

[jan]

Hi Leo,
it is "Set Y Home Compensation" in second level Service (password DI), it's in 0,01 mm steps. Take care to not change anything else.
I would still recomend you to interchange Y and M connectors for the encodeur (J4F against J3F). It cost you only 20 minute and two plates, but you would be sure you didn't make any mistake.
Jan