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blackcat4866
11-16-2012, 01:27 AM
I've got three machines in the same building doing this. Most times it's just a single page in the cleaning unit hanging down, causing J31-02 and J17-01 jams. Also C47-05 and C67-18 codes. And the typical streaks when the drum isn't cleaning. At the beginning it was always the blue colored paper, but lately some of them have been white paper, some simplex, some duplex. The one machine collects two pages: one inside the cleaning unit and one between the primary charge and the drum, causing gray images with no vestige of the original image (the optical path is blocked by paper). The last few have re-occurred at 1 week intervals.

Copy counts between 700K and 500K. I've PM'ed all of these machines with the 500K kit. The transfer separation charge units are clean and look good. I ran the high voltage auto adjust today, just for kicks. It's my understanding though that separation voltage is controlled by the potential control, and I'm more likely to cause problems than fix them by setting/changing the separation settings. Today I've also enabled transfer assist for first side images (DIPSW 15-0 set to 1). It's my understanding that transfer assist is normally triggered on second side images and heavier weight media.

I've watched hundreds of pages pass. There is no problem with the operation of the drum claws and solenoid, separation charge, and transport suction fan. The paper never "floats" down onto the bed, like a shorted s/t unit might cause.

What have you seen? The drum will not continue to survive these wraps.

MAD0RAM
11-16-2012, 01:50 AM
I have this happen every so often by multiple machines and it goes away as fast as it happens.
I think it has something to do with humidity or lack of.

I think the problem is in the transfer sep unit and possible carbon build up that cant be seen.
Replacing the unit has always worked for me.

blackcat4866
11-16-2012, 01:55 AM
Thanks MADORAM. I'll get an s/t unit on order. =^..^=

kalindd
11-16-2012, 08:58 AM
I had similar problem with Konica 7085. It was caused by the registration clutch, paper was released earlier and the drum claws were still in lower position, combined with temp and humidity factor, there you go.
But here in Bizhub 950 it is motor, so it may be something else.
Check you image lead edge, if it vary, it may be cause of your troubles.

Or try to disable "drum potential sensor" dipsw 6-7 from 0 to 1 then run High voltage adj. may be your drum is over charged. Did you check your drum ground?

Good luck.

blackcat4866
11-17-2012, 02:43 AM
Check you image lead edge, if it vary, it may be cause of your troubles.

I haven't noticed any variation in the image registration, but it's certainly possible. Less likely, I think, with a registration motor.




Or try to disable "drum potential sensor" dipsw 6-7 from 0 to 1 then run High voltage adj. may be your drum is over charged. Did you check your drum ground?

I ran the high voltage auto adjust, but had not shut off potential control. Does it matter?
A bad drum ground usually produces heavy background and potential control errors. I'm getting neither of those. The errors I am getting are the result of paper blocking the potential control and IDCS. Symptoms, not causes.

Also, I doubt that the drum peculiarity adjustments would have completed successfully if there was a bad drum ground.
=^..^=

kalindd
11-17-2012, 02:54 PM
I ran the high voltage auto adjust, but had not shut off potential control. Does it matter?

As far as I know it matters, this is taken from Konica service manual:
" DipSW 6-7 - Drum potential auto adjustment:
This bit determines whether drum potential adjustment is to be made using a drum potential sensor. This setting is
used to check whether an image problem has been caused by a faulty drum potential sensor."


A bad drum ground usually produces heavy background and potential control errors. I'm getting neither of those.

Totally agree with you.
Good luck.

HoonBoy
11-17-2012, 03:52 PM
Hi, i used to work on the bizhub pro's 1050, and now regularly work on Bizhub 601/751... Does the 950 have the multi feed sensor? and is it activated? Had a few bizhub 601/751 having this problem every now and then... until i noticed finally that the problem was caused by the multi feed of a certain tray.. solved by a simple replacement of the separator roller...

blackcat4866
11-17-2012, 04:04 PM
Hi, i used to work on the bizhub pro's 1050, and now regularly work on Bizhub 601/751... Does the 950 have the multi feed sensor? and is it activated? Had a few bizhub 601/751 having this problem every now and then... until i noticed finally that the problem was caused by the multi feed of a certain tray.. solved by a simple replacement of the separator roller...

Is it activated? I'll have to look. It makes sense thought, at least for the one that collects the paper in the primary. The paper removed is always blank. Lets say two lapped sheets feed up to the separation. The first page will exit, but the separation will shut off before the second clears, and perhaps it wraps. And it may not even show a jam if the machine wasn't expecting the second sheet.

How simple. =^..^=

MAD0RAM
11-21-2012, 10:37 PM
Did you find the issue?

blackcat4866
11-25-2012, 06:32 PM
We haven't eaten any paper in the last week. I've got an s/t unit and PF rollers on order. They'll go into the first machine that eats more paper. I'll post any new information. Thanks. =^..^=

MAD0RAM
12-04-2012, 12:09 PM
We haven't eaten any paper in the last week. I've got an s/t unit and PF rollers on order. They'll go into the first machine that eats more paper. I'll post any new information. Thanks. =^..^=


Thats what I was saying we have it happen off and on throughout the year and it stops as quick as it starts.

If it persists past a few times change the unit if not I think its just a change in the humidity or something.

blackcat4866
12-05-2012, 03:25 AM
Thanks, madoram. =^..^=

blackcat4866
12-07-2012, 09:44 PM
Still OK. The only productive thing that I did was enable transfer assist for first side. And remove the paper scouring the drum.

Did I fix something? Odds are: "unlikely". Probably something environmental that I'll never understand. =^..^=

blackcat4866
12-15-2012, 05:10 AM
Three out of four machines in this building digested more paper yesterday. Some blue, some white. All of the pages I removed today were printed on at least one side, so no evidence of double-feeds ... of course the wrap would be printed, and the blank passed through to the tray with the rest of the printed set.

There has got to be something environmental going on here. It's just too coincidental. Humidity or lack of it? Batch of paper? Power events?
I wish I had the tray #3 rollers with me today, but they aren't here yet. This is bugging the shit out of me. =^..^=

MAD0RAM
12-15-2012, 11:02 AM
Three out of four machines in this building digested more paper yesterday. Some blue, some white. All of the pages I removed today were printed on at least one side, so no evidence of double-feeds ... of course the wrap would be printed, and the blank passed through to the tray with the rest of the printed set.

There has got to be something environmental going on here. It's just too coincidental. Humidity or lack of it? Batch of paper? Power events?
I wish I had the tray #3 rollers with me today, but they aren't here yet. This is bugging the shit out of me. =^..^=


What makes you think it is tray three rollers?

And all copiers in same building!
Sounds a lot like it's environmental to me.
Try the T/S unit on one of them and see if it helps.
Was it the same three from the original post?
If so, Better yet swap the unit from the one that did not do it with one that did and see if the problem goes with the T/S unit.

blackcat4866
12-15-2012, 02:46 PM
What makes you think it is tray three rollers?

And all copiers in same building!
Sounds a lot like it's environmental to me.
Try the T/S unit on one of them and see if it helps.
Was it the same three from the original post?
If so, Better yet swap the unit from the one that did not do it with one that did and see if the problem goes with the T/S unit.

90% on the paper in these machines feeds from tray #3, except when some idiot re-programs the paper size to 8 1/2 x 11W. I could also swap with the one unaffected machine. Yes, one machine remains unaffected. Not a bad idea ...

Thanks MADORAM. =^..^=

methogod
12-16-2012, 04:47 AM
i would stop combining the issues into the same problem. We have 7 920s running, and we see this with higher meter machines.


You need to pull all the "pretty" covers, and ozone filters in back, make sure there is a good 12 inches of air between the back and the wall. In our case we removed some of the left side covers between engine and finisher (but we are in a print shop so no one cares how they look). You can do this as well but its not always needed.

Most of the time the drum claws are not being replaced as needed, and what happens is toner gets into the springs and they stick, i would check drum claw assembly replace claws and springs as needed.

Also i would jig the doors and watch till it happens, is the paper just riding up into the cleaner or is it flipping over (180 degrees), 1 issue would be claws other issue would be lower corona unit or adjustments.

what are the exact meters...

lets try and be specific, it helps us help you.

blackcat4866
12-16-2012, 04:08 PM
... You need to pull all the "pretty" covers, and ozone filters in back, make sure there is a good 12 inches of air between the back and the wall. In our case we removed some of the left side covers between engine and finisher (but we are in a print shop so no one cares how they look). You can do this as well but its not always needed.
....

In a high school? What are the benefits again? I mean other than looking like a car wreck?

These users cannot manage to install toner properly or choose the correct paper size. Do I trust them not to stick their fingers into a rotating fuser? No ... but it would be fun to watch.


... Most of the time the drum claws are not being replaced as needed, and what happens is toner gets into the springs and they stick, i would check drum claw assembly replace claws and springs as needed...

I have kept the claws replaced on schedule and the claw area get cleaned regularly.


... Also i would jig the doors and watch till it happens, is the paper just riding up into the cleaner or is it flipping over (180 degrees), 1 issue would be claws other issue would be lower corona unit or adjustments...

How much time do you have? The last event was 4 weeks ago, three machines the same day. Honestly I don't think I can justify spending the next month sitting in front of a 950 with the doors keyed.


... what are the exact meters...

lets try and be specific, it helps us help you.

750K to 956K. I really don't consider this to be higher count. I've heard of machines with 18M prints.
Honestly I appreciate that you're considering the problem, but so far I haven't heard anything useful or practical in the last bit. =^..^=

methogod
12-16-2012, 08:43 PM
Call a tech, why ask for help but then say you don't have time to test and fix.


Buy 24# paper from staples, should solve most of your issues.

blackcat4866
12-16-2012, 10:42 PM
Call a tech, why ask for help but then say you don't have time to test and fix.


Buy 24# paper from staples, should solve most of your issues.

Well aren't you funny.
I've 12 hours in on each of these machines. I was aiming for some productive time.
Three hours of staring at the bed of a machine that is not wrapping doesn't count as productive, but I've done it.
Again, thanks. =^..^=

methogod
12-16-2012, 11:27 PM
Sorry i can be more help. I have 7 920's running, usually only one does this at a time when its cold out side, low humidity.

would look to environmental if they all have the same issue.

blackcat4866
12-16-2012, 11:59 PM
Then it's down to the last resort. Charge up the cell, pull up a chair, and call the dreaded hotline.

ZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZzzzzzzzzzzzzzzzzzz zzzzzzzzzzzzzzzzzzzzzzzzzzzzzz.......zzzzzzzzzz... .............huh, what? yeah I'm still on the line. =^..^=

JR2ALTA
12-17-2012, 03:00 AM
Can you fashion some mylar? If not to solve problem at least it would be a customer clear till you figure it out.

blackcat4866
12-17-2012, 03:14 AM
Can you fashion some mylar? If not to solve problem at least it would be a customer clear till you figure it out.

Just out of curiosity where would this mylar reside? Perhaps in the drum claw area?
Any mylar that was not on edge would interfere with transfer and separation, so it can't be in the s/t unit.

A) I can hear my own words coming back to me: ... if the drum claws are necessary something else is wrong. The paper should never touch the drum claws if separation is working properly.

... except separation is entirely controlled by potential control. It takes me back the the s/t unit again.

Here's another extraneous theory: This customer incorrectly changes the paper size to wide paper 8 1/2 x 11W. Could the paper slight size difference throw off the drum claw solenoid timing? Again, see A)
It wouldn't be that hard to permanently keep the drum claws contacting the drum. There would be some additional drum wear, but it couldn't be worse than scouring the drum with paper in the cleaning unit. I think this will be my temporary measure.

I don't know ... just random thoughts. =^..^=

CraigW
12-17-2012, 04:51 PM
Are they using "sheet and cover insert" by chance ??

You mentioned the blue paper.

We have some 7155s & 7255s that will get paper into the recycle section quite often when using that application.

blackcat4866
01-12-2013, 03:12 PM
I suppose it's possible. I've got a new theory but don't know what to do about it.

The last couple occasions it has been the green colored paper in tray #2 ... and the enduser has erroneously selected 8 1/2 x 11W manual paper selection for that tray. Perhaps the difference in paper size changes the timing for the drum claws? This time the paper made it all the way to the developing unit, blocking the flow of developer over the mag roller. The copies were very light. And potential control seeing light patches, toned up the developer. Strange that you can get light prints from severely over-toned developer ...

As an experiment I'm "adjusted" the drum claw solenoid so that the drum claws always contact the drum. I know that will create additional wear at drum claw locations, but it can't be worse than scouring the entire surface of the drum with paper. We'll see if it makes a difference.

=^..^=

methogod
01-12-2013, 08:09 PM
usually when this happens the claws need new springs - or they are very dirty. if you already took care of that, i would replace lower corona. intermittent failure will cause curling.

ALSO MORE INFO ABOUT STOCK...

20# OR 24#? you try flipping the paper, one way or the other. We use alot of colored paper - pink mostly, sometimes there is a heavy curl, and if you load it the wrong way - it will snag here and there.

you don't want to use the 8.5x11W (wide setting), unless the paper is larger then then 8.5x11. Never messed with it, but never known anyone to use it.


Good luck....

RRodgers
01-12-2013, 08:57 PM
Every time I see this I always replace the T/S unit and that fixes it. It seems the meters are a tad low for it but you might have cracks in the plastic that is causing it to arc.
Just my $.02
HTH

JR2ALTA
01-12-2013, 09:27 PM
there's really no sense in posting if you're not going to read the whole thread.

The separation/transfer unit was replaced

methogod
01-13-2013, 06:51 AM
insight on these mid-light production black and white machines...

they have a mind of their own...

i have 7 920's running...

2 for some reason have a weak bias (T/S) weather its new or not.

no point trying to figure out what it is....


we just run our stock set at PINK or GREEN, darker colors get a higher charge- its in the service manual/theory.


if its white 20# getting stuck, run as color yellow, if its blue, run as the next color up that increase the T/S...

ill do some research.

usually its the high voltage unit but we have never replace just work around, but we are also a print shop not retail.

RRodgers
01-13-2013, 07:06 PM
there's really no sense in posting if you're not going to read the whole thread.

The separation/transfer unit was replaced
I did read it, don't remember seeing that he did. But in retrospect I believe Blackcat know's what he is doing.

blackcat4866
01-13-2013, 07:42 PM
... but in retrospect I believe Blackcat know's what he is doing.

Hah ... that makes one of us, but thanks RRogers, I appreciate the support.
It's not like KM was doing anything to help.

Sadly being under the bus is the norm, not the exception any more. =^..^=

blackcat4866
01-18-2013, 12:39 AM
Machine #2 ate 7 pages of white paper yesterday, three in the primary, four in the cleaning unit. Machine #2 got the full time drum claws today.

If this is effective I'll try an intermediate step. In DIPSW 07-4 (set to 1) I can keep the drum claws engaged through the entire job, rather than just a few milliseconds at the leading edge. Transfer assist for side #1 hasn't helped. I'll post any updates. =^..^=

MAD0RAM
01-18-2013, 11:00 AM
Did you ever try the T/S unit?

methogod
01-18-2013, 12:01 PM
yes they have replaced both...


but i did just think of another issue, on the older machines 7255 7272, after 3-5m the machines lost bias at the drum.

blackcat4866
01-23-2013, 01:43 AM
... we just run our stock set at PINK or GREEN, darker colors get a higher charge- its in the service manual/theory.


if its white 20# getting stuck, run as color yellow, if its blue, run as the next color up that increase the T/S...

I've been giving this some thought (while fishing blue paper out of the cleaning unit today). What possible difference could it make to label the paper as a different color? Then I remembered that this machine uses a reflective registration sensor. Perhaps colored paper reflects back less light to the receiver? So today I made sure that each tray is properly matched with the correct paper color. Thanks again for the constructive suggestions.

=^..^=

blackcat4866
02-24-2013, 07:05 PM
Following up: I think methogod hit the mark with his comments on paper color settings.

The full time drum claws prevented multiple wraps, but also resulted in broken drum claws, and didn't entirely stop the wraps.
I would frequently find 5 or more different colored papers in a single tray. I worked with the keyops to designate trays for the most common colors. After a lot of resistance, we finally agreed to try it for a week.

I must say I really enjoyed this conversation. Six teachers are in the room, talking amongst themselves, while I'm talking with the office person:
office person: " ... you don't understand. Teachers are just too ... well, dumb to make these settings by themselves." ***new silence***
me (glancing over at the audience): "That can't be true." addressing the audience: "You can learn how to make paper settings, can't you?"
audience (everyone speaks at once): "Of course, we use the machine all the time ... " office person rollers her eyes.
me: "Who can join me for a minute, to look at these settings?"
audience: "Yes, of course ..." everyone follows me.
(office person could not have played her part better. Everybody wanted to prove her wrong. I was delighted. And she may be right about teachers, but it got the desired result. I got their undivided attention for 5 minutes.)

Zero jams that week. Shall we try another week, Yes? And so on. I think they're starting to see the benefits. And I may not be an idiot after all (at least not about that one thing ...). Thanks methogod. =^..^=

methogod
02-25-2013, 12:55 AM
I aim to please....

i have seen some random stuff with this series 920/950's...

We run (at my shop) alot of self mailers, just duplexed 8.5x11 on several (7) of them, mostly on PINK, Yellow, and other color paper (always 24/60#). I have 2 machines, one with over 17 million and the other with 9 million that for some reason like to get caught at the drum, never had it wrap completely as BLACKCAT did, but similar issues.

I think its from one of the HIGH VOLTAGE UNITS NOT HOLDING AT THE CORRECT VOLTAGE DURING PRINTING, so even though in a normal office you would WANT TO REPLACE THE FAULT, the best test is to run all paper set as PINK or YELLOW, which will slightly change the VOLAGES ALL AROUND, and help make the paper stick to its paper path.

I always keep a spare fuser ready to swap out because they fail early all the time. Sometimes web issues, other times just uneven wear on the rollers. I would stay away from GENERIC toner with these unless you have the recycling unit installed. Just a head ache you can avoid.

Biggest draw backs are warm up time in general, cold start time (over 7 minutes), i would think in a office you would not let it go to sleep just LOW POWER, but that does shorten the life of the fuser as a entire unit.

Some suggestions for productions shops are take off all the safty covers over the fuser, and the process unit, pull the ozone filters, they don't stop the fine toner any way.

I hope they fixed the fusing issues in the next series... but i doubt it...

bobe
08-28-2015, 04:48 AM
did you figure out what was wrong?

Paul Ridds
08-28-2015, 08:26 AM
Just like to say this thread has been a real pleasure to read.Better than a course on the machine in many respects. Keep up the good work.

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