Konica C6501 Images shift

[nwpmikey]

Hi..

Please see images attached

We are having problems with our C6501 where the magenta image shifts exactly 56mm when printing

Any stock any weight, duplex/simplex.

I am the end user, we have had engineer replace all circuit boards in the engine, all lasers replaced, fuser, drums, basically there is nothing left that has not been replaced..

last ditch attempt was to replace the creo rip with a fiery, this has been done and the problem still occurs..

has anyone got any ideas please..

 

[MailGuru]

Wow! That's a new one on me !

If everything inside the laser has been replaced, and, the RIP has been replaced, I would think, by deductive reasoning, it might be the art file (only component left). Is the 6501 the only color laser you have (can you run it on another color laser to see if the problem follows to the other laser)? If not, can you output the art as a PDF then view the PDF?. If the PDF looks fine, you might try looking at exactly where the printer itself is located. Is it near any electro-magnetic field that could interfere with the positive/negative charge of the toner and the coretron? Sorry nwpmikey, all I can think of.........Maybe someone else on this forum can help.

 

[nwpmikey]

Sorry forgot to mention, it can happen on any file at all, its totally random, doesn't happen on all files all the time,

let say file 1 prints 300 sheets ok, file 2 image shift, come in following day and file 1 with have image shift if i reprint it, and file 2 willprint ok...

sometimes i can get 5000 sheets out ok, sometimes only 10...

 

[Joe Duffy]

Sounds more like a paper edge sensor or a timing issue than anything - loosing track of paper and shifting image.
Is it always Magenta? Is it always the same direction(I assume minus scan direction)? Is it always the same amount?
Never had this issue before on my 6501 - just fishing here.

 

[Emtri]

As a konica tech...this is new one.

Its definitely not your rip of files. It wouldnt be the fuser. My guess would be the magenta write unit or one of the boards..maybe a reg sensor or something? You said they've already replaced a lot though Do you know exactly which boards have been replaced. Perhaps theres something in the motors that drive the drums thats slipping?

 

[nwpmikey]

Hi, it always shifts in the same direction, always exactly 56mm and it is mostly magenta, but once in a while cyan..

Every single board in the main imaging unit has been replaced, every sensor has been replaced, all 4 lasers replaced, all rollers replaced, fuser changed..., all drums changed, all coroans changed, basically everything that can be replaced has been...

firmware was updated to 70 and made no difference so changed back to 60, our last ditch attempt was a rip change and that made no difference..

 

[Joe Duffy]

WOW!
Only thing I can say is troll this forum:
Copytechnet Home
and read. It is for techs, so you will not be able to post but maybe you can find a answer in a existing forum.
Good Luck.

 

[MailGuru]

I swear, it sounds like a gear slippage on one of the motors. Years ago, we had one of the original KM 6500's, and, many of the motor cogs and gears were made of plastic. Those plastic teeth would wear down, or even break off in some instances, which would make the paper slip and registration way off.

 

[Joe Duffy]

I swear, it sounds like a gear slippage on one of the motors. Years ago, we had one of the original KM 6500's, and, many of the motor cogs and gears were made of plastic. Those plastic teeth would wear down, or even break off in some instances, which would make the paper slip and registration way off.

Or maybe the allen key holding the gear is not tight enough and the gear is slipping... but when he said it happens on Cyan also and always the same 56mm then I doubt it could be either of these.

 

[MailGuru]

Joe Duffy's probably right. Gear slippage would not result in the exact same 56mm -- it would be too intermitent and all over the place. Could be gremlins.......(I hate those pesky little critters!!!!).

 

[kalindd]

Check here,
Error Code KM C6500 Magenta shifting

 

[nwpmikey]

Thanks for all the replies, we have managed to solve the problem..

Still don't know the exact cause, but our engineer said all he could do now was another Pm Service, and since then it has not happened, run at least 8000 sheets and all good so far..

what annoys me is we still do not know the exact cause, but at least we are up and running......