PDA

View Full Version : Bizhub 250/350 eating drums


Custom Search


Pages : [1] 2

fixthecopier
05-15-2008, 11:36 PM
I just became aware of this problem as I was leaving the shop. The service manager has a 250 and a 350 with same problem, machines are in different locations. The 250 has 260,000 copies. The drum and developer were changed at 200,000. It lasted 42,000. Changed it and it lasted 7,000. Changed it and it lasted 7000. Dave says it is sucking developer to make copies and killing the drum. Drum charge, hv parts, and all the usual have been changed. Has anyone seen this?

pierre
05-16-2008, 01:13 AM
hi there,

When you replace the drum unit,You must replace the developing unit too

fixthecopier
05-16-2008, 02:03 AM
No, not on the bizhub. You change the drum and put new developer in the dv box. But anyway the whole unit was changed last tlme.

Rudi
05-16-2008, 01:31 PM
I am sitting with the same problem and you are right i think the dev unit should only be replaced every 400k copies.This was never a problem on the di 2510.

nmfaxman
05-16-2008, 02:43 PM
There are mylars on the dv unit that tend to warp and scratch the drum.
Trim the mylars or replace dv unit.

ni311
05-16-2008, 04:39 PM
You don't have to change the dv unit, unless the mylars are broken, you're right. I usually also check the two rolls on both sides of the developing roller. At around 100k, I'm changing it. There isn't a fixed number to change these parts, depends on many factors.
Did you change the transfer roller assy?

redhotrob
05-19-2008, 11:56 AM
Have you replaced the transfer roller?

fixthecopier
05-20-2008, 10:27 AM
Sorry about being slack about your question. Yes the transfer was changed, and made no differance. I will get some more info today and update.

fixthecopier
05-20-2008, 02:05 PM
OK, here is the fix. The DV collars are getting contaminated when the new developer is put in[ being sloppy ]. When you change the developer, be very tidy and clean up. So one of the eariler post was correct that changing the dv box should cure the problem. As this is an ongoing problem we are trying to get a part number for the collars so we can fix it ourselves. I will update.

artfer
05-21-2008, 02:33 AM
The DI-1611 / DI-2011 DV Collars are the same as this one and have part number on the parts manual.

wagon
05-21-2008, 08:14 AM
OK... I used to rebuild hundreds of di250, etc. IU's a year and since they are mostly the same as all the later stuff you will need :

1) The dev spacer rollers (at each end of the mag roller).. started in Di183. The one at the drive end wears the most, so you can often just change that one. Put a (tiny) amount of grease on the shaft before installing the rollers.

2) Inspect CAREFULLY the mylars at each end of the mag roller. They get worn and holes develop, causing dev to come out. This happens most on units with stuffed spacer rollers. If the spacer rollers are kept good you may never need to change the mylars. These, once again, are a Di183 part. You may need to glue the mylars in... I think they sometimes come with a self adhesive stuff, but I can't remember. Take care with their alignment when installing.

3) Superglue, into the dev unit casing (after cleaning), the shaft the drive gear that is driven by the machine runs on. Then lightly grease the shaft.

I apologise for not posting part numbers - I don't work on these anymore, so I am going by memory. Hopefully this will help. In actual fact, these tips apply to every model 'based on' the Di250/350 engine - so, Di350, 351, Biz350, 3510, etc.

Wagon.

ni311
05-24-2008, 08:17 AM
For Bizhub 1611/2011 the part number is 4163-5298-01 and it's called ROLL

fixthecopier
05-24-2008, 06:26 PM
Thanks for all of your help. I love this site.

kingarthur
08-12-2008, 04:32 PM
I just became aware of this problem as I was leaving the shop. The service manager has a 250 and a 350 with same problem, machines are in different locations. The 250 has 260,000 copies. The drum and developer were changed at 200,000. It lasted 42,000. Changed it and it lasted 7,000. Changed it and it lasted 7000. Dave says it is sucking developer to make copies and killing the drum. Drum charge, hv parts, and all the usual have been changed. Has anyone seen this?

The "official" answer from Km in the uk is to tape paper over the mylars when emptying the dv units, as, apparently, when you tip over the units to empty them you are contaminating the collars. What we do is hoover out the units without tipping them up, this way the dv units seem to be lasting.

stebro
08-19-2008, 03:11 AM
KM's fix: In the BH 250, I think they are now sending a plastic sheet with the new developing unit so you can cover the rollers etc. while doing the dev change.. . DO be very gentle when lifting the top cover of the d/u and flipping it over.. this is a weak spot and as questionable a design as i have seen in my 27 years in this biz.. if the cover moves more than a half an inch side to side, the control mylars just come off.. And I HAVE had this problem with a 2510 & a 3010.. I thought I'd be smart and just do a d/c in these just like in the BH250.. It tested my & the customers patience until I found out what I'd done :o.

Dave10
11-25-2009, 10:03 PM
The stuff about being careful with developer is crap. I know this is what they say at KM, but we are ALWAYS careful about this. We use the mylar covers included with the drum and are very careful when adding developer, and we still get this problem over and over. There is something else going on.

Hansoon
11-25-2009, 10:26 PM
Some observations I made for another panel some time ago. Perhaps of any use for you though slightly out of context since this was a very long thread overthere:

.......the "nub" on the transferroller is sliding on the drumsurface. Its doing that since the days of the Di-250/350 series and was never causing problems. Old machines with transferrollers over 300K even have the nub being "dug" out by the drums without new drums suffering. The nub is there to keep the distance drum-transferguide constant.

Beside the nub is a small circular disc like roller with a very fine edge. A mark of this edge can be found on the drumsurface but until now never damaged the drum. This disc roller (or collar) keeps the distance transferroller-drum constant.

The distance drum-mag roller however is regulated (or kept) by another disc like roller or collar as Minolta calls them. This roller is sitting on the end shaft of the mag roller and runs also on the drum surface. If worn it can cause drum jitter (most of the larger Minolta's) or in case of the smaller digitals, Di-152/183/250/350/200/251/351 and Bizhubs 200/250/350 will cause ripping of the mylar at the end of the mag roller. Strangely enough almost exclusively the rear one, the driven side, never the front one. The momentum from the gears may be the reason this happens only at the rear of the unit.

However, what seems to happen is that the hole in the collar wears out by the time and becomes larger and at the same time the circumference of the collar wears off too. This wear in total allows the mag roller to come nearer to the drum surface with the mylar inbetween. Eventually the surface of the drum will grab the mylar and rip it off in the direction of the drum rotation. That's the beginning of the end. Re-attaching the mylar with tape doesn't work. The distance between collar-mylar-drumsurface and the strain working on the mylar seems too strong to keep it in place.

The only solution is replacing the collars or at least flip their place from front to rear.

It seems that the new toner/developer of the Bizhub series is more abrasive and that's probably why the Bizhub's are obviously having more often problems than the older Minolta digitals though this very same construction is in use since many years.

The abrasiveness of the toner/developer might explain why Minolta wants the collars being covered when doing the developer change. Hence the mylar strips supplied with a new drumunit to cover the collars avoiding toner or developer particles coming near the collars.

As I mentioned before do I take out the mag roller anyway for cleaning the developer unit and this gives me the opportunity to clean everything well, collars and the shafts, and also allows me to change the collars from front to rear of the mag roller. Measuring the hole and circumference of the collars with a micrometer show a significant difference between of new and old one and also the collar running in front and rear.

and:

A) The drum is fixed and steady in its position by the two metal pins molded in the plastic side covers who in turn are fixed to the developer unit base. Later units have unfortunately a plastic pin which breaks easily.

B) The nubs on the transferroller bushings ride on the drum surface and are there to keep the distance of the spring loaded movable guide of the transferroller constant to the fixed drum.

C) The thin sharp edged collars sitting beside the transferroller bushings ride on the drum surface and are there to keep the distance of the spring loaded movable transferroller itself constant to the fixed drum.

D) The collars sitting on the end of the mag roller ride on the drum surface and are there to keep the distance of the spring loaded movable mag roller constant to the fixed drum.

H) Between the surface of the fixed drum and the surface of the spring loaded movable mag roller are two mylar seals (or guides). The seals are fixed to the base of the developing unit in the cavity under the mag roller. The seals are than led from under over the surface of the mag roller and are attached to the doctor blade with another adhesive piece of seal.

I) The distance drum surface to the mag roller surface is critical not only for the copy quality but also for providing enough space for both seals.
The distance drum surface to the mag roller is determined only by the size of the collars at both mag roller shafts. This distance decreases, especially that of the rear collar, because of excessive wear (probably caused by abrasive toner/developer particles). At a certain point the collar(s) are weared down so much that the gap between the drum and mag roller is not sufficient to keep the seal from being touched by the turning drum. When the drum surface grabs the seal it will be ripped off in the direction the drum turns, in this case downwards.

and:

We manufacture now ourselves collars with an integrated bearing to avoid early wear.

http://img205.imageshack.us/img205/2416/collarbh350.jpg (http://img205.imageshack.us/i/collarbh350.jpg/)

This is a preliminary version, I think to reduce the outside diameter of the ball bearing to 10mm instead of 13mm to have more plastic "meat" around it to avoid cracking of the plastic when getting old.


Hans

fixthecopier
11-25-2009, 10:37 PM
You are correct. The last few I changed were because the small piece of mylar that is on each end of the mag roller, tucked up under the cover. This strip is coming out from under the cover, on the right side, and bunching up and digging into the drum, pealing the finish off.

srvctec
12-15-2009, 04:16 AM
The stuff about being careful with developer is crap. I know this is what they say at KM, but we are ALWAYS careful about this. We use the mylar covers included with the drum and are very careful when adding developer, and we still get this problem over and over. There is something else going on.


Yeah, I know it's CRAP since I'm the one who initially started a ticket on this with KM shortly after the BH250/350 series came out. KM came to the conclusion that we were making a mess of things when that is absolutely not the case. Something changed between the 3510 to bh350 series since we NEVER had a single failure of ds collars on 2010-3510 series machines. We even had a developer unit last over 600k which is impossible with the bh350 series. We've tried everything we can think of- removing the stupid sponge spacer, trimming off the mylar that goes the full length of the doctor blade, moving the thin white ptfe washer that comes installed on the front side of mag roller near the ds collar to the inside between the seal and frame. Nothing has worked. What we really need is to have a source for ball bearing ds collars that are of correct diameter as shown in the above post. I bet the developer units will go to 400k like they are supposed to with ball bearing ds collars!

So, where can we buy these collars Hansoon? :D

Hansoon
12-15-2009, 06:02 AM
So, where can we buy these collars Hansoon? :D

Custom made collars are available, another production will start next week. Just send me a PM or an e-mail:

nospam@rex-technika.com

Hans

HelpdeskGuy
12-15-2009, 06:06 AM
The problem is the ds collars particularly the rear one get worn and the dev is rubbing on drum we have fixed this prob by replacing dev unit every 3 drums instead of every 4 as per manufacturer guidelines

Dave10
12-15-2009, 02:48 PM
Can anyone post the part numbers, please?

Hansoon
12-15-2009, 06:15 PM
Can anyone post the part numbers, please?

Part # for what?

Hans

Dave10
12-15-2009, 07:49 PM
The collars for the DI-1611/DI-2011. Sorry I didn't make it plain before.

SmellsHot
12-16-2009, 12:17 AM
On the bizhub 200,250,350,222,282,362's I've been shutting of the "please change pc drum message" to avoid having to replace these as much as possible. I've had several units run close to 300% But when I do replace the parts, i just replace a new dev unit as well as the drum and developer. This has been working well for me, since i'm saving money by not having to replace the drum and developer at 100%
Very seldom do they crap out before the 100%

To shut off the message, you just need to change DIPSW 418, bit 3 to a 0
Happy Holidays to all!!

srvctec
12-16-2009, 12:36 AM
The collars for the DI-1611/DI-2011. Sorry I didn't make it plain before.


Ummm, it's already been posted in this very thread. Post #12 (http://www.copytechnet.com/forums/29652-post12.html)

Dave10
12-16-2009, 02:04 PM
Thanks. Sorry.

kingarthur
01-07-2010, 04:25 PM
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

pantsman
01-07-2010, 04:43 PM
try swapping the drum for a fuser roller as it is made out of harder material.

Hansoon
01-07-2010, 05:59 PM
try swapping the drum for a fuser roller as it is made out of harder material.


Thread too complicated for your dilletantic mind, Idiot??

Hans

minimerlin
01-07-2010, 10:18 PM
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 .CheersI 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
01-08-2010, 08:08 PM
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
01-15-2010, 10:31 PM
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
01-17-2010, 01:17 AM
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
01-17-2010, 03:40 AM
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
01-18-2010, 05:25 PM
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
01-18-2010, 06:02 PM
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
01-27-2010, 03:04 PM
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
01-27-2010, 04:55 PM
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
01-28-2010, 04:09 AM
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
01-28-2010, 04:34 AM
I'll ask a very stupid question: do the color series (C350) have this problem too ?

minimerlin
01-28-2010, 08:06 PM
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
01-28-2010, 08:08 PM
I had a feeling I would a similar response :)

barratec
01-29-2010, 10:51 AM
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
01-29-2010, 11:02 AM
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?? :D:D:D

Hans

Hansoon
01-29-2010, 11:13 AM
Just discovered that the # given in the Italian instruction is that of the collar for the Di-183 series. This collar is NOT the same as in the Bizhub or Di-250/351 series. The collar for the Di-183 has a diameter of 18.35mm against 18.60 for the Di-250/351 series machines. I cannot imagine that this will work though the drum has the same diameter in both machines, the mag roller is slightly thicker. Perhaps that's why the collars must be slightly larger. Furthermore, when the mylar seals at each end are damaged they need replacement too at the same time.

Hans

barratec
01-29-2010, 01:30 PM
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

I've seen right now that there's the same technical notice about BH 222-282-362 models. NEW MODELS OLD PROBLEMS.......!!

P.P.S.: i apologyze but i did a mistake : the right p/N of the collars is 4163529801 and not 416352981. Sorry!

Hansoon
01-29-2010, 06:15 PM
4163529801 (4163-5298-01) is the # for the Di-152, 182 collar. NOT Di-250, 351.

Hans

Hansoon
06-08-2010, 10:23 AM
http://www.copytechnet.com/forums/sale-trade-wanted/33726-modified-collars-bizhub-200-250-350-di-series.html

Hans

Hansoon
07-17-2010, 05:47 PM
Here's an Instruction how to replace the collars on site leaving the starter in:

http://www.copytechnet.com/forums/sale-trade-wanted/33726-modified-collars-bizhub-200-250-350-di-series.html

Hans

Custom Search