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seniortech
10-13-2010, 08:42 PM
Is anyone out there having any problems with small black spots on C6500 Black drums?

I have been to 5 different machines over the past couple of weeks, all in different enviroments and on every machine have had to change the black drum because of small black spots on the drum.

The machines are well within the 200K service interval and have done between 20K and 80K.

Thanks

jma676
10-13-2010, 09:11 PM
Someone or something is damaging the Drums, I think you mean that the sensitive area of the Drum was damaged, leaving a small point.

In some cases of high humidity, can cause this fault for a crash, but I guarantee that in normal conditions this does not happen, maybe if you hit with something or someone. :)

jrf
10-13-2010, 09:14 PM
I have only 2 of these machines but i have had to replace 3 drums in the last 2 weeks because of blank spots as a result of tiny marks on drums.

seniortech
10-13-2010, 09:30 PM
The drum surface is not damaged, with a small piece of cloth you can flick away the small toner spots and the green drum surface seems perfectly ok. however they will quickly return usually within 2K. Replacing the drum is the only option...

Avalon
10-13-2010, 11:42 PM
This is a known issue to do with the coating on the drums, TAUS1000512EN00.
The only recommendation is to fit the 102C drum part no.A0400Y4

ineo+6501
10-14-2010, 04:12 PM
What Avalon said.......... Fit the new type drum from the 6501. 102C.

seniortech
10-14-2010, 04:48 PM
The 102C is the only type of drum we fit...

jma676
10-14-2010, 05:21 PM
Konica Minolta Bizhub Pro C5500/C6500/C5501/C6501/C65hc Drum Unit (DU-102)

Originally: DU-102
Actualization: DU-102B / DU-102C

hosman80
10-15-2010, 01:35 AM
now that you mentioned i have had the same problem a few times in the last month with those drums (DU-102C), i wonder if they had a bad batch of drums....

RRodgers
10-15-2010, 03:46 AM
Has it been hot?

seniortech
10-15-2010, 05:42 PM
The temperature at all sites was no more than 70 degrees F. 3 machines were in clean air conditioned rooms. I had to replace another drum today with exactly the same problem. hope we are not seeing a problem similar to the blade flip problem we had a couple of years ago...

HORSE
10-16-2010, 12:33 AM
On this subject ....I'm saying nothing :D

Stirton.M
10-17-2010, 11:10 AM
Usually this problem is primarily due to humidity, or in the past, poor cleaning blade contact.

Cleaning with a dry cloth is usually enough to fix the problem. I generally prefer to use methanol as it cuts through the toner a little easier. Just be sure to wipe the drum dry after before you retalc. Sometimes drum shock may be present, but this disappears fairly quickly.

buster68
10-18-2010, 04:36 PM
We are having the same problem here. On all our 6500s, no matter the environment, temperature or humidity. We ordered some drums from Katun and have had excellent results. I think KonicaMinolta has changed the cleaningblade rubber for the 102C drums that causes this problem.

jma676
10-18-2010, 05:43 PM
We are having the same problem here. On all our 6500s, no matter the environment, temperature or humidity. We ordered some drums from Katun and have had excellent results. I think KonicaMinolta has changed the cleaningblade rubber for the 102C drums that causes this problem.


Drums Drums Drums, The Curious Case, Katun has no Drums Formulated for Bizhub Pro C6500, Only for Bizhub Pro C500, these products have good performance, but will never be better than the OEM DU-102.

Katun only offers Rebuild Kit, and the framerate will depend on the state of other components, such as lubricant for cleaning roller Brush.

Maybe you been able to adapt these to the Bizhub Pro C6500, because it has a wide range of stabilization Control , but I don`t believe that it is functioning properly.
DU-101 is not compatible with the D-102.

In addition, If what you say is true... Katun should announce it such as compatible with both DU Types, But.. they are not.

seniortech
10-18-2010, 06:09 PM
Becoming a joke now another 3 black drums on 3 seperate C6500 machines today with black spots all over them, tried cleaning as Stirton M suggested, ok at first, but spots were back after several hundred prints, had to resort to changing the drum to cure problem...

jma676
10-18-2010, 07:09 PM
Becoming a joke now another 3 black drums on 3 seperate C6500 machines today with black spots all over them, tried cleaning as Stirton M suggested, ok at first, but spots were back after several hundred prints, had to resort to changing the drum to cure problem...



Maybe you have another problem and not the Drums Unit, if you refer a.. One black dot on the surface of the drum.. that yields a white point on the print image according to where it is located.

If the case is many black dots on the image, maybe your problem is the toner or developer.

With a sample image would be easier.

maily
10-19-2010, 03:16 PM
Try to change the paper gms on the setting,if missing you need to replace the developer due to overlife span ,co's u reset the counter.

mapracing
11-17-2010, 11:02 PM
We have an account with a C6501 that is having the same black mark issue on the drums. We have replaced the Drums several times, Developing units, Developer and corona assemblies. This looks like the same problem with the bad drum lot from awhile ago. If anybody comes up with a solution please let us know.

Tonerjockey.com
11-18-2010, 07:15 PM
Wonder what would happen if you swapped one of the color drums for one of the black? Would the spots stay with the drum or would new spots develop on the black drum?

mapracing
11-18-2010, 08:18 PM
We have done that it develops with the black drum. We also get it with the color drums but not as often. We went back today and replaced all the filters and vacuumed all the duct work thinking that it might be a heat problem but only time will tell at this point. We did notice that one of the ventilation ducts was clogged so hopefully this helps and the customer allowed us to put a fan behind the machine to blow more air through the filters.

Tonerjockey.com
11-18-2010, 08:56 PM
The clogged ventilation makes sense.

Stirton.M
11-19-2010, 09:02 AM
I would agree with the ventilation as well.

Though I haven't had this problem in some time, I have noted that on occasion that if I see toner dust building up in and around the process carriage, this is a strong indicator that the toner/ozone filter box on the right side is likely clogged and needs new filters. These should last 200K as they come with that kit, but this is not always the case. I keep a bunch of these filters in my trunk stock for just such occasions and make a mental note to check during calls for other issues. As I said, I have not encountered this drum problem in some time, so the filter changing might be a factor in keeping that issue at bay....or simply a coincidence...I am not sure...aside from knowing that I rarely have to clean the process carriage area to the extent I would have to with severely clogged filters.

mapracing
11-19-2010, 03:20 PM
I will keep you guys posted if the filters and cleaning the air ducts did the trick as we are keeping a close eye on this machine.

racefreak
11-20-2010, 12:59 AM
I've had this same issue on all my 6501s (only model and the like I work on). All drums are the 102c and I have no fuser exhaust filters and I keep the toner filters clean. These specs show up regardless of age of the drum unit. Some show up 10K after being replaced, others 100k or never. Being in the southern US, humidity is a big factor. I clean the offending drum with alcohol on a t-shirt rag and then replace the drum with a color unit (usually yellow). Make sure you run the set up adjustments and most times it won't come back. If it does, replace the unit. FYI...The toner filter has 8 of the white cloth filters in front of the single ozone filter. If you remove 1 or 2 of the white filters every time you go, by the time you run out, it will be time to replace it according to the counter.

My understanding is SSD is still working on a permanent fix but this seems to work for me.

HORSE
11-20-2010, 01:52 AM
Try swapping the black drum with drum that's in the magenta position and putting a new drum in magenta instead.

Wouldn't waste you time debating filters, it nothing to do with that.

mapracing
12-03-2010, 08:08 PM
As racefreak has stated. SSD has confirmed there is a problem with the coating on the drums and it has been escalated to Japan. I will keep you guys informed once they respond to my ticket. For now we are just replacing the drums in the color unit and using that drum for Black.

Stirton.M
12-05-2010, 04:33 PM
Just had a chance to review some of my course material related to the 6501 differences to the 6500, and according to that, the drum units for the colour were DU-102, and the black was DU-102B.

That said, we are now up to DU-102C. And of course, we, in my shop anyway, did not make any distinction between them. We stuck the same drum in all colours and simply kept an eye on them. It is rare that we get them now....likely due to the changes made to the DU-102C over the previous generations...the older ones, we suffered a lot of blade flipping, spots on the drum were not so much the problem. we compensated the blade flipping for a time by using the blade and plastic couplings from a C500 drum unit, which seemed to resolve both issues.

Duppsko
12-08-2010, 10:39 AM
I've had the same problem with one of my machines. But it was always on the yellow drum. Replaced the drum, and it could work for some days or weeks. This was solved when I took a PM and changed the developing unit at the same time. Now it has worked fine since the PM.

Trek
12-14-2010, 05:47 PM
We have this issue on 2 6501's, we changed the DU-102C in the black position for an old DU-102B but the problem came back.

All developers are changed, all filters clear, fans working ok, ventilation good. Copy quality adjusted properly, but the issue comes back after 2500 prints.

Does anyone have the definate fix for this?

empiru
02-28-2011, 10:59 PM
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
03-01-2011, 12:04 AM
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
03-01-2011, 03:31 AM
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
03-01-2011, 04:34 AM
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
12-05-2011, 06:38 PM
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
12-05-2011, 07:20 PM
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
12-05-2011, 07:22 PM
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
12-06-2011, 01:43 PM
Yeah, I end up with this solution, too... I am keeping my fingers crossed :)

seeb
12-06-2011, 02:40 PM
By changing the starter along with the drum I have had good success at getting rid of the black spots on the drum.

seniortech
12-23-2011, 12:54 PM
No Call backs to the machine where we fitted 2 DU104 drums, seems to be working, fingers crossed :o

dljorg
01-24-2012, 11:53 AM
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
01-26-2012, 03:50 PM
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
01-26-2012, 03:56 PM
Finally they admitted we were right, once again.

seniortech
02-04-2012, 04:25 PM
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
02-06-2012, 01:14 PM
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

ni311
02-07-2012, 09:20 AM
The latest info I saw about this subject from KM is that it is a problem with the cleaning blade, we were advised to replace the initial cleaning blade from the du-102c with the one that it is fitted du-104 but without giving us a part number for this blade. The main difference between these two is an anti-vibrating piece that is on the cleaning blade of the du-104. Also, if you are doing this, you have to update the firmware on the machine with a version that was not released yet... This last process prevent the cleaning blade to flip, same problem that was present on the first du-102.
Anyway, it is much easier just to change the du-104 as a whole. I'm not sure if it is cheaper or not.

Bizhub
02-07-2012, 09:07 PM
As everyone has said .................................

Fit Du104 drums and throw the 102 (A B or even C's) into the bin. This is becomming more and more the norm for K-M ! They keep cutting costs and reliability is now suffering.

We have heard excuses about temp , humidity and even too many black and white copies made !!!!!!

ni311
02-08-2012, 10:35 AM
After drawing the final line, I'm not sure KM cut the costs. I'm sure a lot of du-102C returned to the manufacturer. I just hope it won't apply the same measure to du-104.

ineo+6501
02-08-2012, 10:44 AM
I'm told by a reliable source that KM will soon release a TAD/TNI regarding this in the near future (in the UK).

The fix will be to fit the DU-104 drum.

ni311
02-08-2012, 11:54 AM
I'm told by a reliable source that KM will soon release a TAD/TNI regarding this in the near future (in the UK).

The fix will be to fit the DU-104 drum.

It is already out. The id is TNEU1200014EN00, it appeared somewhere in the first days of February 2012. This was available for Europe region.

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