Xerox 700 NVM Mottle

[jotterpinky]

We own a Xerox 700 DCP that we're having mottle problems with on heavier stocks (250-300 gsm). It seems to depend on the color. The black seems to print pretty dense, however when printing colors like dark blue it gets very mottled looking. I'm assuming this is due to the 200% ink coverage rather than 100% with black. We have used the "black mottle patch" in the past to change the NVM value on the 740-043 chain link. This slows the machine down but results in a much better black on certain stocks. However when we set this NVM value to the "mottle mode" it actually makes the blue's appear much more mottled. Regular mode gives better results but still not satisfactory.

My question is this: Is there another NVM setting we can change that will go "the other direction" as far as making voltage changes etc that would yield a better blue (less mottle)?

 

[kalindd]

What is your SW level? Upgrade it to 3.1 if its not done by now.

 

[mariewilliam1]

i dont know in deep about it, but your post has a learning experience for me. Also give suggestions for cheap letterhead printing
Thanks a lot in advance.

 

[SteveL]

That NVM is not a fix for mottle, it's a workaround for gloss differential.
Have a look at the image transfer adjustment settings in custom paper settings (that is the adjustment for mottle).

 

[jotterpinky]

I changed the image transfer settings so it looks the best - which is 50%, however it seems as though Xerox has limited this functionality too much since it seems as though it just got better and better the lower the number. Of course 50% is as low as it will go. Can the technician adjust this further in service mode?

After looking through the custom paper stock settings I'm wondering what the "regi-nip" adjustment does. It looks like it corrects for reigistration problems but how is this different from creating an alignment setting for the sheet? It appears as though Xerox has provided next to nothing in the way of documentation for this feature and it's uses.

 

[kalindd]

Service tech can adjust the transfer to higher or lower.

 

[airyk]

we had this issue with thicker GSM stocks and Xerox actually sent us a modified Fuser to help with this issue which seemed to work fine.