Image defect on KM 6501 - OCE-CS665

[kmcopier]

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

[Gerry.Fitz]

tech

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]

[SEnder]

Same problem

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.

[dljorg]

Copy Mark on Black Halftones

Little hard to tell from your image but it looks like a jitter or speed matching problem caused by the transfer belt or fuser interacting with the paper - worse on heavy stock.

Transfer belt unit is OK and rollers replaced? Second transfer too?

KM says this is a characteristic of the machine and cannot be totally fixed. Hmmmmm....

This is a cut from article 40 in the KM Troubleshooting Guide for the C6501:

The next things can be done to reduce it:

Admin settings: Set Thick paper black mode to ON.
This under [utility] 03 Adm. settings. 06 Common Settings.
Then 1 times pres NEXT. Set it ON.
Normally when you make a black monocolor copy only the black first transfer roller is active. What this does is activate all the rollers. Effect is to put a brake on the transfer belt and hopefully stabilize its speed and reduce the jitter.

OK so play with it between -5 and -35 or more if you dare. Check the FD Mag adjustment when you are done so image size is correct.


After enabling by service (SW1, bit0) the key operator can reduce the pressure by changing the paper tray setting.
DIP SW setting shows Process Adjust button in the paper settings. In Process Adjust section there is a setting for 2nd transfer pressure - again the idea is to reduce the possibility of jitter so try normal and light.


This screen is to adjust in:
Utility [button]
03 Machine adm. settings.
01 Sytem setting.
05 Expert adjustment.
07 Quality adjustment.
05 Custom screen.
Then set for Line 2 and Dot 2 the type to TYPE 2.
Changing the print screen can mask jitter marks by altering the pattern of dots laid down by the lasers under some circumstances - definitely worth a try. Change the screens used by the copier in machine admin mode and then select Dot 2 instead of Dot 1 in the print driver.

BEST SOLUTION SO FAR
1. Do all the stuff above.
2. Lie to the machine about the paper weight in the tray - select 81-105gsm. This makes the motors run at high speed - more torque means less jitter.
3. You have to go to the Process Adjust screen mentioned above and raise the fuser temp and pressure to compensate for higher speed and make sure fusing is correct.

This is not a complete fix but pretty darn close.

Best Regards from the snows of Connecticut!

[RRodgers]

Do the Fuser line speed adjustment and that should fix it. Play with it (line speed) until it goes away.