Dc12 white spots

[technic]

Prints have some white spots with a black spot in the center which appear ramdomly, but not in all prints. It seems that some developer grains are falling from the developers units. I have already change the developer units and the developer material for each color, the copy cartridge, the 2nd BTR and the IBT along with the rollers that bias the IBT as I got the info from a tip, besides I replaced the plate that bias the developer unit once this one is in position facing the drum during the rotation.

Any help with this will be appreciated.

[xcopytech]

check bpo roll contact

[technic]

Thanks xcopytech,

I also replaced the contact roll (59K08160), Bias roll (59K07800)and the back up roll (59K07812), cleaned the metal plate that touch the contact roll, the CMYK image is better now but printing the pattern # 22 for each color the problem is still there...

Any other suggestion?

Thanks in advance.

[xcopytech]

bpo roll is metal roll in copy cartridge.
for some reason developer dot came on drum and then on paper.
this roll should prevent that.
maybe you have to check roll contact in machine and hvps which provide high voltage for drum unit.

also high temperature and humidity can produce this problem

br

[technic]

Thanks, I will check it out...

[sachin]

Have you tried tone up in max set up
mail me your id on : agrwalsachin@gmail.com

i will send you the solution page form the manual

[TechMate]

we have had similar problems here which was resolved, try checking

1. contaminants in the rotary dispenser and rotary auger
2. HVPS may have unstable voltage supplied due to a leaky capacitor
3. paper/ stock used may be damp
4. ESV connections may be loose
5. condition of the drum
6. condition of the CC/PCC HVPS and Deve Bias HVPS
7. natural conditions (humidity, relative room temp., etc)

[technic]

Thanks techmate, I will check it out.

[Veedle]

You have what is known as DCD's - Debris Centred Deletions, probably showing up mostly in cyan and magenta.
The components in the rotary toner dispenser are breaking down - the only permanent fix is to replace the components in the rotary dispenser, vac out the dispense tubes and replace the affected developers.
Messy, but it works...

[Dexor]

help on white spots

Check the attachments, I have white spots showing up, mostly cyan, and sometimes tiny pinhole size black dots inside can showup anywhere, but much more rare. Dev material changed a few thousand copies; similar issue in the past with black pinhole sized dots was resolved by putting seal on the rotary frame vs. black developer housing; this time changed all seals - no go.
I try to locate developer housing repair kits 655N131 & 655N132 in the manual but can't find it....
Any ideas?

[GusG]

Paper dust?

[copymaster2000]

Dear,

White Spots with black spot i.e. developer at Centre is mainly due to your paper supply.It would go for sometime after replacement of Developer ,However improper media with high paper dust causes the paper dust to accumulate in Developer Module which causes this problem.Try filtering developer with chalni & try using better paper.
Pls give me feedback.This Customer should be user of Cinar Mass 12x18 250 gsm paper if I m not mistaken.If yes, Ask him to shift to lykem.

[Dexor]

Dear,

White Spots with black spot i.e. developer at Centre is mainly due to your paper supply.It would go for sometime after replacement of Developer ,However improper media with high paper dust causes the paper dust to accumulate in Developer Module which causes this problem.Try filtering developer with chalni & try using better paper.
Pls give me feedback.This Customer should be user of Cinar Mass 12x18 250 gsm paper if I m not mistaken.If yes, Ask him to shift to lykem.

thanks for feedback. Filter developer - what is "chanli"?
I have also noticed bias roller in transfer roller assembly can cause this problem, will update in a few days.

[Dexor]

I have outher idea!!!!
The toner housing... when it cames old, it starts to lose some plastic material.... its a goes Mix whit the toner.
Clean it or replace it.
good luck

I've just replaced bias roll @ transfer belt unit, and replaced dev units with new material - NO CHANGE!
Looks like I'm going to have to do what you suggest - toner housing - and it's a big job; I'd seen it once my friend doing this while I was laughing - now it's my turn not to laugh