Xerox 700 Bad Print with Spots

[Kombetar]

Hi there,

we have a problem since a while when we print on our Xerox 700. On the Magenta and Cyan prints only, some darker spots appear. Please check test prints in the attachments. It should be a solid print with 20% and 80% tint, but these darker spots appear.
They dont appear in 100% tint prints.

Can someone help us out identify the problem? Did someone had a similar problem?


Thank you,
Kombetar

 

[PricelineNegotiator]

Looks like your machine has acne. I recommend switching to a diet without any greasy foods, possibly a vitamin B supplement (pantothenic acid).

In all seriousness, it sounds like your laser is the culprit, but maybe some more educated users can be of better help.

 

[DYP]

How new are the drums and the developer housing?

 

[PricelineNegotiator]

Also, are the spot cyclical or random? Do they repeat every x inches?

 

[Kombetar]

Also, are the spot cyclical or random? Do they repeat every x inches?

The spots are random and dont repeat. They are more dense on the far sides of the print and appear less or not at all in the middle of the print.

Drums are new and the developer housing are 50% used. But I don't think the problem is from any of the both.

 

[Kombetar]

Attached are two close ups of the print.

 

[MailGuru]

What paper stock are you using?

 

[Kombetar]

it appears on all kind of papers and stock

 

[MailGuru]

I don't know what that is. Have you called in your tech reps?

 

[mohamed.aitslimane]

I have a Xerox 560 i had similar problems on few occasions, but just on some sheets, i never really got to find the reason but since it disappears i suspected the paper, i am no expert thought.

 

[sidneykidney]

I think it looks like you've got contamination in your Magenta Dev Tank. You need to change the developer for whichever colour has the spots. This has happened to me a few times before and it seem to happen after paper dust from an uncoated stock got into my dev tank.

The Xerox engineer came round and emptied the developer and then refilled with a new batch.

 

[mojoprime]

i think they're right. there's some dust or something getting in the developer. but i have to tell you, the 700 gave us fits like that. seemed like it was always going from something like this tp mottling to something completely new. but i think our tech checked the laser and the developer housing and vacuumed the crap out of the whole machine.

 

[DYP]

Don't discount that it isn't the 2nd BTR. Also check the Secondary Transfer Voltage.

 

[adriansto]

Nothing to do with 2nd BTR.
This image quality defect is named ' oil spots' and there are several procedures to do.
Most important is to rise K developer bias to 530 volts and change some machine nvm's.
Ask your tech to look into bulletin database about 'oil spots'

 

[Kombetar]

thank you guys for the advice. Will talk to out tech.

 

[Stochastic]

I think it looks like you've got contamination in your Magenta Dev Tank. You need to change the developer for whichever colour has the spots. This has happened to me a few times before and it seem to happen after paper dust from an uncoated stock got into my dev tank.

The Xerox engineer came round and emptied the developer and then refilled with a new batch.

Yup. Dirty Developer. Get rid of it and replace it.
Have seen similar issue with parting powder getting into the tanks. Some companies love to absolutely smother their pre-printed stocks in tons off parting powder and then expect a digital device to print 1000's of variable records over top. That works fine......until the next HQ job....