C6500/C6501 Black spots on Black Drum

[empiru]

We have the same problem with 2 different C6500.
The solution is to lower the toner density on black: Process Adjustment, Process Fine Adjusment, Toner Density Fine Adjustment.

[jma676]

It seems that this problem is to become common, and it seems no one has been able to identify the causes of the problem, I've had this same problem a long time ago .. But with the DU Yellow, provided every 20K or 10K 5K, consider the time that the problem could come by the use of stickers to the impression, that appeared after printing them, the case was then assessed in erratic again, this led me to think that any game should be defective supplies such as toner, the truth is also that after you start using the new DU-102C this problem was appearing in a very low percentage. curious case.
Apparently believe that under some conditions of humidity and temperature, the toner, appears to merge with the Drum by the friction of the cleaning blade along the Drum, this is my particular opinion, you can cleaned easily with cotton moistened with Drums cleaner.

Attached are some pictures KMBT Bulletin.

[Stirton.M]

It seems that this problem is to become common, and it seems no one has been able to identify the causes of the problem, I've had this same problem a long time ago .. But with the DU Yellow, provided every 20K or 10K 5K, consider the time that the problem could come by the use of stickers to the impression, that appeared after printing them, the case was then assessed in erratic again, this led me to think that any game should be defective supplies such as toner, the truth is also that after you start using the new DU-102C this problem was appearing in a very low percentage. curious case.
Apparently believe that under some conditions of humidity and temperature, the toner, appears to merge with the Drum by the friction of the cleaning blade along the Drum, this is my particular opinion, you can cleaned easily with cotton moistened with Drums cleaner.

Attached are some pictures KMBT Bulletin.

I'm not a fan of putting anything liquid on the surface, it sometimes leaves a bit of residue on the drum where it was cleaned. It eventually disappears, but is still a hassle to the end user. I prefer to simply use a soft cloth and gently rub the contaminate off that way.

[jma676]

I'm not a fan of putting anything liquid on the surface, it sometimes leaves a bit of residue on the drum where it was cleaned. It eventually disappears, but is still a hassle to the end user. I prefer to simply use a soft cloth and gently rub the contaminate off that way.

yeah !!! this is really true, no liquid***, but the truth is I've found the perfect formula that leaves no residue on the Drum surface, and this is a secret, but there are many cleaners to the sensitive surface on the market, I do not remember marks because I do not use them, but it is also true that rubbing with anything on the Drum can be abrasive and also is a strenuous and tedious task,::::: the real solution is: .::::: Replace DU:::::. no cleaning.

[ni311]

Re: C6500/C6501 Black spots on Black Drum

I got the same problem, it appears especially on one C6501. I have 4 in the same room, with almost the same counter and suddenly one of them started to destroy the drums. After cleaning the drum, in a few hundreds prints, the spots appears again. The only solution until now is to change them, but it is just a temporary solution because are not lasting for long. Any ideas?

[racefreak]

Re: C6500/C6501 Black spots on Black Drum

In Atlanta, We've started replacing some of the worst offenders with DU104 drums (C7000). We have had mixed results. Mostly positive. Some, not all, of the machines have stopped giving us the little specs on the drum. I believe it to be a difference in the coating on the drum. The 6500 series is rated for 200k and I believe the 7000 is for 250k or 300k. The only physical difference I could find between the 2 drums was the addition of 2 little purple arrows on the frame of the 104 drum for the ORU-M. I can't believe KM would add another drum to its line for 2 purple arrows so there has to be something in the coating. There is a price difference for that drum. Mine is about $24 dollars more for the 104 but if it keeps an additional call from being placed, it's paid for itself.

Again, this is not a 100% fix, but it might help. SSD is aware we are doing this and asks us for feedback so it may be something they're working on.

[seniortech]

Re: C6500/C6501 Black spots on Black Drum

I have today put two drum units from a C6000/7000 in a really problamatic C6501, as I have been reliably told that you will not get the black spot problem with this type of drum. I will know within a few days if this has worked, watch this space...

[ni311]

Re: C6500/C6501 Black spots on Black Drum

Yeah, I end up with this solution, too... I am keeping my fingers crossed

[seeb]

Re: C6500/C6501 Black spots on Black Drum

By changing the starter along with the drum I have had good success at getting rid of the black spots on the drum.

[seniortech]

Re: C6500/C6501 Black spots on Black Drum

No Call backs to the machine where we fitted 2 DU104 drums, seems to be working, fingers crossed

[dljorg]

Re: C6500/C6501 Black spots on Black Drum

This spots on drums thing is an epidemic. KM just released a note today 1/24/2012 admitting there is a problem with both small spots on black and to a lesser degree on yellow as well. Temporary fix is to use a #104 drum from the 7000 series but only on black.

There will be a new drum with production beginning in March that will require a firmware update to make it work right. No doubt the KM site will have the stuff when it arrives.

Do not confuse this problem with the earlier one mentioned above and the change between the 102 lettered drums. This is a different problem altogether.

Like the many comments about ventilation and filters and agree with your techniques but am afraid that has no effect here.

As a temporary measure have tried two things with limited success.
These work only on new drums. Seems like when a unit is contaminated that's the end - whatever it is is on the brush and can't be removed.

1. Remove the cleaning blade from the drum unit and bend the metal support so that the center is about 1mm closer to the drum than the edges. Idea is to increase the blade pressure in the center where the spots seem to be worse.

2. Disassemble the drum unit and remove the wax bar and tension springs. Take the crossbar off, both main bearings out and remove the end plate with the two white gears. Out comes the drum cylinder. Carefully remove the stick-on seal around the cleaning brush support and pull out the cleaning brush. The wax bar is then right there. Know this sounds hokey but the result is a drum that will go 50K rather than 2k before the spots show up again.

[eifling]

Re: C6500/C6501 Black spots on Black Drum

Best thing we did was to start putting C7000 drums in our C6500's. Way less service because of drums and no more having to wipe the black drum every 2k sheets. Oh and its way cheaper.

[ni311]

Re: C6500/C6501 Black spots on Black Drum

Finally they admitted we were right, once again.

[seniortech]

Re: C6500/C6501 Black spots on Black Drum

This spots on drums thing is an epidemic. KM just released a note today 1/24/2012 admitting there is a problem with both small spots on black and to a lesser degree on yellow as well. Temporary fix is to use a #104 drum from the 7000 series but only on black.

There will be a new drum with production beginning in March that will require a firmware update to make it work right. No doubt the KM site will have the stuff when it arrives.

Do not confuse this problem with the earlier one mentioned above and the change between the 102 lettered drums. This is a different problem altogether.

Like the many comments about ventilation and filters and agree with your techniques but am afraid that has no effect here.

As a temporary measure have tried two things with limited success.
These work only on new drums. Seems like when a unit is contaminated that's the end - whatever it is is on the brush and can't be removed.

1. Remove the cleaning blade from the drum unit and bend the metal support so that the center is about 1mm closer to the drum than the edges. Idea is to increase the blade pressure in the center where the spots seem to be worse.

2. Disassemble the drum unit and remove the wax bar and tension springs. Take the crossbar off, both main bearings out and remove the end plate with the two white gears. Out comes the drum cylinder. Carefully remove the stick-on seal around the cleaning brush support and pull out the cleaning brush. The wax bar is then right there. Know this sounds hokey but the result is a drum that will go 50K rather than 2k before the spots show up again.

Interestingly, why are the spots appearing mainly only on black and yellow? there are various theories doing the rounds relating to temperature/ enviroment, does anyone know the reason for sure? The DU104 drums seem to be doing the trick on my problem machines.

[eifling]

Re: C6500/C6501 Black spots on Black Drum

Someone told me there was a change in the coating on the drum and it would make black stick more easily. Also heard it was a problem with the cleaning blade.

I stopped worrying about it when i went to the du104 also