Bizhub c452 Centering

[Mitch Barron]

Hello everyone.

I have been getting rather personal with a 452er the last few days and was hoping someone would maybe be able to shine some light on the problem. I'm sorry if my terms are wrong (I learned everything in German), but ill try my best. The machine I am working on has been working wonderfully except for a problem that arises every so often. The machine intermittently prints a print job where the centering is way off, but the rest are perfect. Lets say I print 20 different jobs at 10 pages a job. The first 5 jobs are perfectly printed then on the 6th the first 3 pages are printed offset (4-6.5 cm) to the right. My initial thoughts were the RAM and I have since changed it out, but the problem persists. I am thinking it is definitely a electrical component (PCB?), but wanted to touch base with you all first. Any thoughts?? I have attached a master just so you can see what I mean. All the best! Thanks a lot in advance.

Take care!

MitchSINEO 28415062517100_0001.jpg

[allan]

Re: Bizhub c452 Centering

In what direction is the shift?
Is the shift in main scan or sub scan?
If the shift is in sub scan then it could be the registration that goes of by a bit, even a feed unit could cause this.

I don't think it is processing if you look at the way the lasers work to find SOS (start of scan).

[tech51]

Re: Bizhub c452 Centering

I've had a similar problems on the c654 range which has the same registration system.
The actuater by synch roller(under the paper dust remover) can either get stuck or become lazy returning. I replace the actuater & the return spring which has cured the problem every time.
The first time I encountered this it was very intermittent but gradually got worse over time.
Hope this helps.

[KingofMorton]

Re: Bizhub c452 Centering

Check the original size of the two or three pages that are offset. Also, is this a repeatable offense that is being performed by the MFP? If you print the same pages over again are they always offset?

[Mitch Barron]

Re: Bizhub c452 Centering

Good morning,

Thanks for the replies! The Problem occurs completely random, but apprears to happen at the beginning of a job (first 2 or 3 pages of a separate job). The shift occurs in the direction of the leading edge. I am not too sure where the synch roller/actuator is to be honest either. Am I mistaken or is it the "transfer roller " you are talking about? I again appologize, but what is main scan vs sub scan?? Total Noob. Have mercy.

I will be revisiting this problem on Monday morning so all the help i can get would be greatly appreciated. I hope i can one day repay the favor.

Thanks alot for the help.

Mitch

[allan]

Re: Bizhub c452 Centering

The direction the laser writes in in called main scan. So if you are standing on the side of the machine the shift would be to the left or right. Sub scan is the feed direction and the shift would be up or down.

[tech51]

Re: Bizhub c452 Centering

Good morning,

Thanks for the replies! The Problem occurs completely random, but apprears to happen at the beginning of a job (first 2 or 3 pages of a separate job). The shift occurs in the direction of the leading edge. I am not too sure where the synch roller/actuator is to be honest either. Am I mistaken or is it the "transfer roller " you are talking about? I again appologize, but what is main scan vs sub scan?? Total Noob. Have mercy.

I will be revisiting this problem on Monday morning so all the help i can get would be greatly appreciated. I hope i can one day repay the favor.

Thanks alot for the help.

Mitch

When you open the right hand door, the transfer roller is on the right (foamy looking thing). If you look to the left of it there will be a metal roller with a rubber roller underneath it. These are the synch rollers, so called because they synchronise the paper to the image produced on the transfer belt. The rollers have a grey coloured dust preventer clipped in on the metal roller. If you uncllip it and look in the middle where the paper travels into the two rollers, you will see the actuater I referred to. Hope this helps...