Image defect on KM 6501 - OCE-CS665

[Stirton.M]

Thanks for all the suggestions...
The defect is on all stocks... more pronounced on heavier stock (ie. 250gsm+). If I print a photograph -- the image defect is somewhat hidden, but if I print a greyscale image or halftone -- it is very very apparent.

Try a mixed halftone, with black and cyan. Pattern 53 and 100-120 halftone on the two colours. I want to know for certain if there is no repeat in the cyan. It seems strange that this only affects black and not the other colours.

Swap the drum drive assemblies between black and cyan.

Also, try a complete belt unit swap.

[Albonline]

this looks like a speed blur to me, which would mean somthing is affecting the speed of the black drum or developer units. saying that the heaver the stock the greater the defect points to paper feed system overload. ie motor drawing too much current or slowing so much that the other motors in the copier cant sync with it.(going beyond pll range)

[Albonline]

hint try running a grid pattern, see if image is distorted.

[Gerry.Fitz]

Hi ya
I have had several versions of this problem ...fist can you check if it is media related ..if it is card it will flick and cause a bounce which will give you the line and it will get worse the thicker the card this m/c will only run paper or you have not set your loop or pre registrations correctly.
Gerry

[TonerMonkey]

This is a jitter problem with heavy stock hitting the bottom of the transfer belt causing the mark - a special rom was brought out for the 6500/5500 which racked the CMY transfer rollers out when doing black thus taking the slack up on the belt and resolving the problem.

Best practice would be to make sure firmware is up to latest level. Otherwise I could find out which firmware sorts this problem, it has been known to happen on heavier stock on black only.

[kmcopier]

there is an special docment for this problem. check your techincal information

[Gerry.Fitz]

Hi ya
Would love to check our tech bullitens but as I work for Oce we get no tech info from your selfs it comes from Germany and goes to somewhere in Venlo nether to be seen again...any suggestions would be greatly appriciated
Gerry

[Herrmann]

I have found something, that might help you:

Description
Thick Paper BK mode setting.
Solution
Thick Paper BK mode setting is to reduce banding that occurs 230mm in from the lead edge when printing halftone images with thick paper stock.
Thick Paper BK Mode engages the first transfer rollers on each YMC colors and operates in color mode during printing in B/W mode.
Notes :
1. Use only for thick paper on whichbanding occurs.
2. Sinceprinting in B/W mode operates in color mode, the total counter counts in B/W and the maintenance counter counts in color. It does not develop YMC,
but the life of the developer is shortened since it agitates the developing unit.
3.Concerningcolor printing, after printing more than 1000 sheets in this mode toner scattering or blurred color image may occur.
To enable Thick Paper BK mode, perform the following:
1.Press the Utility button on theMFP and select #3 Machine Admin. Setting.
2. Select #6 Common Settings.
3. Pressthe Next button and select Thick Paper BK mode to ON.
Note : If Thick Paper BK modeoption is NOT displayed, enableit by setting software DipSW 11-5 = 1 (ON).


Hope, this helps

[sbillis]

check humidity and drum memory.

do you have troubleshooting guide?

B：Cause by 2nd transfer Sample No.13
The line occur because speed is slow down in a moment when the thick paper enters the fixing unit

C：Cause by 1st transfer
The line occurs because transfer belt unit shakes when the stiff paper enters the 2nd transfer or
fixing unit. It is occur because the 1st transfer shakes finally
The distance from front edge depends on the color.

D：Cause by 2nd transfer(paper rear edge jumping)
The line occur because shifted by 2nd transfer as a paper rear edge jumps when paper rear edge
passed the guide plate
The line occur stiff paper and distance is 102mm from rear edge


A：Execute the “Automatic Gamma Adj”
★Touch the “Adjustment”->03 Execute Adjust Operation->Touch the “Automatic Gamma Adj”->
Touch the “OK”->Return to the machine state screen
B,C：No countermeasure. Change to soft paper or light paper.
D：Attach film sheet on guide plate before 2nd transfer

[SEnder]

We the same problem with C452, 552, 652 brand new machines. Only in K. Same defect, more visible on thick paper stock. We replaced K module, nothing changes, same.