Bizhub 250/350 eating drums

[minimerlin]

We have a problem with a Biz 250 eating drums, it has taken out 3 in the last month, the last time a new dv unit was fitted. Where the drum is worn lines up exactly with the 2 white plastic protrusions on the transfer roller. Was thinking of reducing the pressure on the springs behind the transfer unit assy. Any thoughts on this anyone .Cheers

I have found that these protrusions (i love that word!) tend to wear down into half moon shapes and then the transfer roller is too close to the drum and damages it. Also make sure dev tank is not leaking as that can cause fast wear.

[Millennium]

KM actually put a bulletin out in regards to this. The transfer roller is the main cause, you'll know if you put a new drum in and it immediately puts a gouge into the side of the drum.

The problem is this gouge causes leakage on the copies, and ends up causing issues with the drum, DV unit, and even the fuser over time.

Transfer roller - every 150k copies. Religiously.

[srvctec]

KM actually put a bulletin out in regards to this. The transfer roller is the main cause, you'll know if you put a new drum in and it immediately puts a gouge into the side of the drum.

The problem is this gouge causes leakage on the copies, and ends up causing issues with the drum, DV unit, and even the fuser over time.

Transfer roller - every 150k copies. Religiously.

I haven't seen that bulletin. But I strongly disagree that is causing the issue since it happens on brand new machines as well as machines that have a brand new transfer roller.

[mascan42]

This is probably a silly question, but are you using the protective mylar sheets when changing the developer? I've had problems with the ends of the drum getting chewed up if developer gets into the collars of the dev roller.

[srvctec]

This is probably a silly question, but are you using the protective mylar sheets when changing the developer? I've had problems with the ends of the drum getting chewed up if developer gets into the collars of the dev roller.

Actually I'm the one who started the first ticket with KM about this whole ds collar issue (ticket #28358 started 02/06/2007). It took them nearly a year to come up with a solution which resulted in the mylars supplied in the drum units. They claimed we were spilling developer into the area around the collars which is NOT what was happening. I'm in my 22nd year of working on copiers (legacy Minolta) and am the senior tech in our office and I don't make a mess of things when changing developer. Not saying it isn't possible that this can contribute to the problem, just that it's not what is causing it in our office. KM just doesn't have a clue what could be causing this and decided to blame it on techs changing the developer. All they have to do is make ds collars like Hansoon is doing (BALL BEARING) and that will take care of the problem for good. But then they wouldn't make much money on parts, would they.

[Millennium]

The only reason I brought up the bulletin, which I misworded. It's actually a TAD in the knowledge base (#TAUS0702492EN06). It talks about banding on the drum.

The issue it bring up was already talked about in this thread (by KingArthur and minimerlin) that the white plastic collars on the transfer roller wear down, causing more pressure on the drum, which forces it down towards the DV unit collars you are talking about.

My company was warrantying a ton of DR-311's at the time. We started replacing the transfer roller immediately, an have seen a sharp decrease in failures of not only the drum unit, but the DV unit and fuser as well.

If you are having the issues with brand new machines, however, I'm at a loss. The collars on the DV unit sit off of the paper image area, so I see no reason it would cause any type of lines on the copy.

[Golfnut27]

Hansoon Bearings work in the BizHub 250/350

Has anyone purchased the modified bearings from Hansoon and do they work? Do they solve the problem of premature developer replacement? Hansoon, what are you charging for the bearings/collars?

If you have any other facts on the performance of your bearings, I would like to hear about it.

Thanks.

[Golfnut27]

Has anyone found a solution to this problem

We are still fighting this problem. Has anyone discovered any type of solution or method to eliminate repeated service calls. Do we need to replace the Developer Assembly with each drum installation?
Right now my service dept. is taking a hit or miss approach, meaning when we need to replace the drum, they inspect the developer and if it looks fine we leave it in the machine.
But in the past, 20-40,000 images later we have a copy quality problem, which requires the Dev. Assembly & a new drum.

As per my previous post, has anyone used Hansoon bearings?

Hansoon would you post any info on your bearings.

Thank you.

[barratec]

Actually I'm the one who started the first ticket with KM about this whole ds collar issue (ticket #28358 started 02/06/2007). It took them nearly a year to come up with a solution which resulted in the mylars supplied in the drum units. They claimed we were spilling developer into the area around the collars which is NOT what was happening. I'm in my 22nd year of working on copiers (legacy Minolta) and am the senior tech in our office and I don't make a mess of things when changing developer. Not saying it isn't possible that this can contribute to the problem, just that it's not what is causing it in our office. KM just doesn't have a clue what could be causing this and decided to blame it on techs changing the developer. All they have to do is make ds collars like Hansoon is doing (BALL BEARING) and that will take care of the problem for good. But then they wouldn't make much money on parts, would they.

I'm in 14th year of working on copiers (Konica, konicaMinolta, Ricoh) my technical supervisor is in the 30th and we agree TOTALLY what you think!

[srvctec]

We are still fighting this problem. Has anyone discovered any type of solution or method to eliminate repeated service calls. Do we need to replace the Developer Assembly with each drum installation?
Right now my service dept. is taking a hit or miss approach, meaning when we need to replace the drum, they inspect the developer and if it looks fine we leave it in the machine.
But in the past, 20-40,000 images later we have a copy quality problem, which requires the Dev. Assembly & a new drum.

As per my previous post, has anyone used Hansoon bearings?

Hansoon would you post any info on your bearings.

Thank you.

My service manager found some ball bearings (a standard part he found on internet) that seem to work on the rear side, but not the front because they are too wide. We first tested it just last week and copy quality was the same with the new ball bearing as it was with a new stock KM part. Time will tell if it will hold up. Will post here when the copier we installed it on has enough copies to prove it works better than stock ds collar. I will find out where he got them if anyone wants to try them.

[Jett]

I'll ask a very stupid question: do the color series (C350) have this problem too ?

[minimerlin]

I'll ask a very stupid question: do the color series (C350) have this problem too ?

In short....No, it is a totally different machine!

[Jett]

I had a feeling I would a similar response

[barratec]

Just yesterday KonicaMinolta Italy sent a new technical notice that in short tells that the problem is caused by the two collars of the developing roller. They suggest to change the DS COLLARs (p/N 4163529801) every 40.000 copies.

P.S.: I'm sorry but the attached file with the procedure is nly in italian

[Hansoon]

Just yesterday KonicaMinolta Italy sent a new technical notice that in short tells that the problem is caused by the two collars of the developing roller. They suggest to change the DS COLLARs (p/N 416352981) every 40.000 copies.

They might have noticed this thread??

Hans