dirty background on MP7500

[aaahmmm]

Dear all
My machine is MP7500 , I have dirty background after less than 50 - 100K it is not even, from one side much than the another my prints always in landscape .you can see attached pics , all the drum unit brushes , blades, developer, transfer all of them are original same as toner . the strange thing that i have 4 machines with same parts i use, the problem on 2 of them and the other 2 are perfect.
Thank you in advance
,

[Counsel]

Re: dirty background on MP7500

My first step would be to take out the pcu and clean and wax the drum (we use nu-finish) and then replace the corona and grid, may help to use a brass brush on the mag roller as well. 9 out of 10 times cleaning and waxing the drum keeps it clean, and i go through coronas a lot before PM is up on these but coronas are cheap.

[sakura]

Re: dirty background on MP7500

Usually when you have such background it is a first sign of a developer going out of business (contamination etc.) Look at the PM counter and if developer has more than 300K then it might be a time to replace it. If you don't have a problem with a drum (my personal opinion - replace everything at the same time - PCU, developer, Blade and a brush) then just "refresh" the developer itself. Initialize. Make laser glass and a density sensor are clean of any toner remaining at the time of initialization. As mentioned before - clean mag roller with Scotch pad and vacuum after that to make it look "like new" (if it has any dark residue which doesn't allow to a developer to "stick" properly and it causes problems.

[aaahmmm]

BACK SIDE ONLY

[Jomama46]

Re: dirty background on MP7500

Thanks for the incidental information. Replace the transfer blade and belt

[femaster]

Re: dirty background on MP7500

My first step would be to take out the pcu and clean and wax the drum (we use nu-finish) ...

Wax? That's the first time I've ever heard that... Sounds like contamination of the drum surface with major problems to follow. Then again, who knows, I've heard stranger things. Don't think I will try that until I see first hand on some elses machine that it works...

[Jomama46]

Re: dirty background on MP7500

Waxing and polishing drums is as old as photocopiers. I havent done it myself since OPCs became the norm. It smooths the surface and prevents toner buildup.

[Counsel]

Re: dirty background on MP7500

Wax? That's the first time I've ever heard that... Sounds like contamination of the drum surface with major problems to follow. Then again, who knows, I've heard stranger things. Don't think I will try that until I see first hand on some elses machine that it works...

Actually our Ricoh engineer that comes and does training updates for us recommends it. So far the best we find is the Nu-finish brand we dont use the zinc dust but on a rare occasion we just wax the cleaning blade and the drum let em dry for 5 or 10 mins while you do whatever else then wipe them off so they are smooth. I haven't had any premature failing issues with drums with this method.

And to the new info I agree on replacing the transfer belt and blade, check the pm count I'm pretty they recommend replacement at like 450k

[Lagonda]

Re: dirty background on MP7500

BACK SIDE ONLY

Are you copying from single or double sided originals? You could have a problem with the contact scanner in the doc feed.

[aaahmmm]

Re: dirty background on MP7500

what you are using for Waxing and polishing? how i can did it

[Polarbear]

Re: dirty background on MP7500

Counsel,

The nu-finish that you speak of - you say it is a wax, but I find only Nu-finish polish? Is this the same product?

Please share how you apply it - the whole procedure please.

[Counsel]

Re: dirty background on MP7500

I guess its technically its a Car Polish we just refer to it as car wax (see picture of bottle). You just take a small dab depending on the the size of the drum, use a nice smooth cloth we use the white or blue disposable towels that are clean and smooth and just rub it on like your waxing your car or polishing your shoes then let it dry after about 10 mins or so you will see a white powdery filming then you take a dry cloth of the same type and just wipe off the film and it will now be really smooth you can feel it when you rub the dry cloth on it how smooth it becomes, we do the same thing to the cleaning blade make sure they are dried and wiped off so they are smooth, then assembly the pcu. Anytime I have to take a pcu apart i always re-polish the drum and blade, and usually wash the charge roller (if its one of the black rubbery rollers) in soap and water and dry it off. The color machines with the plastic nylon type charge rollers i dont wash in water i just use a damp cloth to clean them.


This method seems to work pretty well at keeping toner buildup off we dont use the zinc powder anymore on drums just the polish. This method obviously doesnt work for the new color models where the pcdu is all a kit, we only do this on the models where pcu is rebuilt, anything thats prebuilt in a whole assembly we just replace the pcdu's when they go out.

nu-finish.jpg