[CQ] c550 damaging black imaging unit

[acsolutions]

Hello, I had just replaced a black I/u and after 3000 copies it's back with the same problem! The machine has about 300k on it, all units life almost gone no sign of dumping dev. and all drums look ok. Customer is claiming I/U is defective but is the exact same kind of marks. the marks are toward the front side of the drum and it looks like paper clip or staple damage and the new one has 2 marks on that side only. The only thing that has contact with the drum is the transfer belt, so I recommended the replacement of the transfer unit and black I/U again. any suggestions how this damage could have occured? Thanks

[habik]

Re: c550 damaging black imaging unit

Hello, I had just replaced a black I/u and after 3000 copies it's back with the same problem! The machine has about 300k on it, all units life almost gone no sign of dumping dev. and all drums look ok. Customer is claiming I/U is defective but is the exact same kind of marks. the marks are toward the front side of the drum and it looks like paper clip or staple damage and the new one has 2 marks on that side only. The only thing that has contact with the drum is the transfer belt, so I recommended the replacement of the transfer unit and black I/U again. any suggestions how this damage could have occured? Thanks

I would replace Paper Dust Remover as well..

I remember someone mentioned that the foam from either Transfer belt cleaning mechanism or Paper Dust Remover can crumble and get in to dev of Bk IU causing all sorts of funny things.

Have you tried to look at the actual IU it self. Its a job to take the Drum out but have you looked at it? maybe it got there with sheet of paper feeder from the bypass. I have had occasions where in busy office when they remove staples from originals,,they are everywhere.. Still puzzles me how is it possible that it made its way all around TB and through cleaning system of TB.. and then under YMC IU to the Bk.. (possibly during BW copying as YMC are out of turning) still pretty far.

OR

You scratched it when installing

or

You have shaken the IU when new with the orange mag.sleeve out and made a pile of dev clogging up..... .....naahh..probably not.. don't know..

Interesting indeed..let us know what have you found

[Max Kilby]

Re: c550 damaging black imaging unit

Any chance of an example of the print? Might help to see where it reprints and what the impression looks like.

Thanks

[acsolutions]

Re: c550 damaging black imaging unit

Thanks for the response, today I went out and dumped the dust collection plate under the reg assy. and checked for anything that could have caused this. did not find anything, I told customer I could possibly replace the I/U and transfer unit with used assemblies. as far as sending samples I guess I could there is just two scratches about 2 mm in length. The original I/U was doing the same thing. the machine had run over 3000 copies before any complaints and I had gray scale shots I left with the machine before I left so it's not possible to have scratched the drum on install. also the customer ran a few color jobs before I left. Thanks again