C360 damaging the black drum

[Avskrap]

IMG_20130503_111617.jpg

[SmellsHot]

Re: C360 damaging the black drum

I'm thinking packing material(plastic crap breaks on occasion and falls who knows where), foreign debris or dev unit's not seated correctly....Warranty the dev unit and put a new one in, especially since it seems like the issue started shortly after it was replaced.
Good luck and let us know what you find....

[kingarthur]

Re: C360 damaging the black drum

we had the same problem, just checked the m/c history, it would appear a mylar had come off of the K dev unit at the back & took the drum out

[Avskrap]

Re: C360 damaging the black drum

Thanks for the replies;
As stated, the developing unit is in tip-top shape, no loose mylars or packaging material to be found.
I've removed all the drums, developing units and belt, checking for foreign objects, defects and so forth, but I can't find anything wrong, out of place or broken.
What's weird is that the marks are not all the way around the drum, as per the pic, but just ~1cm long, ~0,2mm wide. I theorize that if there was something scratching the drum it'd be marks all the way around and maybe in one or two places, but this is along the whole length of the drum, basically (as per the PDF attached).

I'm going to go back to the customer on monday after consulting KM, just for the sake of it.

[EarthKmTech]

Re: C360 damaging the black drum

we have 2 machines currently doing this with new everything - drum, dev unit & belt. still works for 3 weeks and is destroyed again. Lock levers and everything PERFECT.

I'm thinking theres a bad batch of something going around, but i'm not sure what.

I have a feeling there is something granular in the toner of a larger than expected size and its grinding against the drum and developing roller, the damage is never continuous and is always in little 1cm long scratches exactly as you mention - probably only occures intermittantly during the time of drum rotation / released developing roller clutch, ie, periodic movement of transfer belt in idle state.

[Avskrap]

Re: C360 damaging the black drum

Thanks, Kitty.
I was about to head to the customer after lunch, got in touch with KM support earlier today but ofcourse they've never heard of the problem. Anyway, they told me to vacuum the hopper completely clean and replace the dev unit, toner and drum. Thinking I'll try that, it's better than nothing...

I'll report my findings!

[EarthKmTech]

Re: C360 damaging the black drum

these machines have "auto refining" black developer, it wouldnt surprise me if this is indeed a bad batch of toner thats gone world wide with the wrong developer size mixed in or contaminated with foreign abrasive particulate from the manufacturing process.

You'd have more luck syringing blood out of a stone than them admitting that though

[Avskrap]

Re: C360 damaging the black drum

Just came back from the customer. Replaced the drum, dev unit and toner. Disassembled the hopper and went through it with the vac. Couldn't see any problems with the toner in the hopper, but I figured it'd be best to start from scratch, so to say. Now we'll just have to see if the scratches come back. If they do, I'm out of ideas. Good thing we've got KM a couple of miles away and they're usually up for some field expeditions, I'll get someone to tag along.

[Avskrap]

Re: C360 damaging the black drum

Just to try to get to the bottom of this I disassembled the developing unit from the customers machine.
When emptying the dev, I noticed small white particles. After getting a bit deeper, I found marks on the magnet roll (whatchamacallit) that lines up with the marks on the drum. Although there are more marks on the magnet roll than on the drum, I figure it'd be a matter of days of the being used together before it eating more of the drum.
Check the pics for the white particles (of unknown origin and material) and the marks on the roll.
Any ideas to what this is? I checked the toner left in the cartridge from the customers machine without seeing anything out of the ordinary.

EDIT: I also disassembled the drum without finding anything except some traces of the marks on the cleaning blade. Since it's more apparent on the magnet roll I doubt that the blade is the problem. I think I'll link this to my closest contacts at KM to see what they think of it.

[EarthKmTech]

Re: C360 damaging the black drum

i think you've just proven conclusively its dud toner / developer. Either in the cartridge or in the developing unit.

OR something is breaking down and mixing with the toner, like a bushing or something in the toner supply unit. Perhaps even plastic shavings off the bottle as it rotates ?

[blackcat4866]

Re: C360 damaging the black drum

How about paper dust? Do you see really excessive paper dust in the machine? It would be fairly simple to use different paper for a while. A particularly poor grade of paper could account for damaging grit.

Does the mag roller clean up? I would suspect yes.

It's probably not applicable, but does anybody remember the mono-component analog Canons from the 90's? After a couple hundred thousand copies, there remained a white ... "dust" in the developing unit, mixed with the toner. It was explained to me that the white stuff was an inert component of the mono-component toner. It had no deleterious affects on the image quality. When the white stuff became noticeable, I would ordinarily vacuum out the developing unit, then re-fill.

=^..^=

[Avskrap]

Re: C360 damaging the black drum

The mag roller doesn't clean up, if you're reffering to the lines. They're marks about 0.1 mm deep. Regarding paperdust, the customer uses really high quality paper and the machine's spotless inside, when talking paperdust.

As stated, couldn't see any wear on anything that could contaminate the dev with the white particles I found. I checked everything thoroughly, believe me. Either, it's a bad batch of toner/dev or there's something wearing down and contaminating the dev.

[Hansoon]

Re: C360 damaging the black drum

What happens to the white particles when you heat them up, do they melt like plastic?

Hans

[habik]

Re: C360 damaging the black drum

How about moisture content sealing resin particles which is within toner...

I have noticed this happening on OEM and non OEM toner... therefore they both must use the same type of resin or at least it is on the same base. It doesn't happen with every customer though.. it wasn't scratching the drum ..it was sticking to it and it could be cleaned of..not all the time it depended on how old the IU was...now I am not talking about the IU being in the machine but rather how long it was sitting on a shelf and mainly where!!

Personally I think silica pack should be in every toner, IU and Dev

[Avskrap]

Re: C360 damaging the black drum

I never thought to heat up the particles and the developer is scrapped now... But they did look like plastic, hard to tell at that size and I haven't got my microscope at the office
This is OEM toner, we only supply OEM parts and supplies.