Mp 9000 random smudge... I'm gone mad!

[NeoMatrix]

Re: Mp 9000 random smudge... I'm gone mad!

Try cleaning / scraping the corona wires gently with a flat-head screwdriver to remove the hardened toner + clean / replace the air filter near the corona c. unit ... and while you're at it clean the main filters as well ... clean / scratch the first 15 centimeters of the drum axis (where the internal contacts of the drum rest) to improve grounding, good work

Re. Clean corona wires.

Spring hook works the best. I clean all corona wires religiously every service. You can feel where the dirt/rust/rubbish is located along the corona wire as you scrap along it with the spring hook.

The Canon guys will argue that scraping removes the gold coating from the wires, and so it does but, the gold coating is removed in a uniform state and the corona wires work perfect still. Well they did when I use to work on Canon many moons ago...

[slimslob]

Re: Mp 9000 random smudge... I'm gone mad!

Re. Clean corona wires.

Spring hook works the best. I clean all corona wires religiously every service. You can feel where the dirt/rust/rubbish is located along the corona wire as you scrap along it with the spring hook.

The Canon guys will argue that scraping removes the gold coating from the wires, and so it does but, the gold coating is removed in a uniform state and the corona wires work perfect still. Well they did when I use to work on Canon many moons ago...

Just make certain that you have new wire with you for when the wire breaks.

[JDYAL]

Re: Mp 9000 random smudge... I'm gone mad!

I find that using a pencil eraser with a just a tiny bit of pressure removes most build up. Plus I always have plenty of wires on standby.

[NeoMatrix]

Re: Mp 9000 random smudge... I'm gone mad!

Just make certain that you have new wire with you for when the wire breaks.

Fairly rare to break a tungsten or gold coated corona wire. The corona wire tension spring does stretch a marginal distance before the wire breaks. In saying that I have broke the very rare corona wire while in a hurry. I have replace miles more corona wire than I ever broke.

You don't have to clean round the total circumference of the corona wire. The wire only has to be cleaned on the top side/outer side facing the drum or copy paper. The rest of the corona wire can stay dirty which makes for insulation.

Don't use the hook end of your spring hook; scrap the corona wire clean using the "U" shape end of the spring hook. If you keep your spring hook long enough; continuous wire cleaning will ware a slotted track in the "U" end of your spring hook, which makes for better wire cleaning.

[blackcat4866]

Re: Mp 9000 random smudge... I'm gone mad!

I've refined my corona cleaning technique:

I pour 1/4 cup of alcohol in a small glass jar. I dip wood handled cotton swabs and swab out the housing. Glass cleaner can short out the blocks, doesn't clean off the ozone as well as I'd like, and does not evaporate as well as alcohol. Then I dip another cotton swab and run it along the edge of the housing under the wire, back and forth 3 times. Then on top of the wire (resting on the edge of the housing) 3 times. Flip the unit lengthwise and again 3 times under the wire, 3 times over the wire.

Next, I lay down a section of newspaper with the grid on top. Dip a toothbrush in the alcohol and scrub the grid in the direction of the diagonal grid pattern, usually left handed on the inside, right handed on the outside. Move the scrubbed grid onto a fresh/clean section of the paper and using your forefinger squeegee the alcohol off of the grid, both sides. If there are any wrinkles or burned marks that the alcohol won't remove, you can stop right there. It's not worth continuing to clean a damaged grid. You won't get an even halftone.

I know it sounds a bit complicated, but you can clean a corona unit in about 6 minutes with a little practice. You'll see a surprising amount of ozone on the newspaper when the alcohol dries. =^..^=

[NeoMatrix]

Re: Mp 9000 random smudge... I'm gone mad!

I've refined my corona cleaning technique:

I pour 1/4 cup of alcohol in a small glass jar. I dip wood handled cotton swabs and swab out the housing. Glass cleaner can short out the blocks, doesn't clean off the ozone as well as I'd like, and does not evaporate as well as alcohol. Then I dip another cotton swab and run it along the edge of the housing under the wire, back and forth 3 times. Then on top of the wire (resting on the edge of the housing) 3 times. Flip the unit lengthwise and again 3 times under the wire, 3 times over the wire.

Next, I lay down a section of newspaper with the grid on top. Dip a toothbrush in the alcohol and scrub the grid in the direction of the diagonal grid pattern, usually left handed on the inside, right handed on the outside. Move the scrubbed grid onto a fresh/clean section of the paper and using your forefinger squeegee the alcohol off of the grid, both sides. If there are any wrinkles or burned marks that the alcohol won't remove, you can stop right there. It's not worth continuing to clean a damaged grid. You won't get an even halftone.

I know it sounds a bit complicated, but you can clean a corona unit in about 6 minutes with a little practice. You'll see a surprising amount of ozone on the newspaper when the alcohol dries. =^..^=

A small piece of wet and dry sandpaper on the corona grid works very well. It will clean Sharp PCU corona grids very nice, which will remove the mysterious ghosting smudge marks that drives some Techs crazy while trying to locate the fault.

Tip for the new guys starting out:
*** Sand papering the corona grid must be done "CAREFULLY", while working in "ONE" direction only... ***

[Phil B.]

Re: Mp 9000 random smudge... I'm gone mad!

A small piece of wet and dry sandpaper on the corona grid works very well. It will clean Sharp PCU corona grids very nice, which will remove the mysterious ghosting smudge marks that drives some Techs crazy while trying to locate the fault.

Tip for the new guys starting out:
*** Sand papering the corona grid must be done "CAREFULLY", while working in "ONE" direction only... ***

I use a bit of green "scrubbie pad" on hemostats to clean ANY wire and grid! ** watch for fibers**

[Mark Bbb]

Re: Mp 9000 random smudge... I'm gone mad!

About 10-15 degrees Celsius

Inviato dal mio SM-G935F utilizzando Tapatalk

This flutuation is very big!
Is the machine standing in a garage, kitchen or bathroom or any other room where water is been used?

[Codex]

Re: Mp 9000 random smudge... I'm gone mad!

This flutuation is very big!
Is the machine standing in a garage, kitchen or bathroom or any other room where water is been used?

No.. It's in a dry room

Inviato dal mio SM-G935F utilizzando Tapatalk

[Codex]

Re: Mp 9000 random smudge... I'm gone mad!

Guys... After almost three weeks without problem.... This morning the problem was back again for a few copies/prints... The last thing i changed three weeks ago was the black lamp assembly, together with the 2nd cleaning blade mechanism........ I think i need a priest now... Or an exorcist

Inviato dal mio SM-G935F utilizzando Tapatalk

[Mark Bbb]

Re: Mp 9000 random smudge... I'm gone mad!

No.. It's in a dry room

Inviato dal mio SM-G935F utilizzando Tapatalk

What kind of room is it?
Is there a working ventilation system or not at all?
How often is the air turned over in that room?
I think that the room has no ventilation at all, and that the only ventilation is done by opening the door ...
The less this door is opened the more moisture fills the air and v.v.

[imaginemoko]

Re: Mp 9000 random smudge... I'm gone mad!

what's our PM count? pre charged and charged unit and in cleaned? like no arching on where the spot appear? is the charged frame are free from worn out like a foam seals from ozone filter and its frame? development unit entrance seal is good, like some toner may came up to charge unit? when swapping parts does it appear same time for a few copies it will appear? may i suggest after cleaning the charged unit just leave the right side, side cover and run the auto process then run some jobs for observation, best of luck Sir.

[Codex]

Re: Mp 9000 random smudge... I'm gone mad!

A small piece of wet and dry sandpaper on the corona grid works very well. It will clean Sharp PCU corona grids very nice, which will remove the mysterious ghosting smudge marks that drives some Techs crazy while trying to locate the fault.

Tip for the new guys starting out:
*** Sand papering the corona grid must be done "CAREFULLY", while working in "ONE" direction only... ***

Already changed the charge unit and the 2nd charge unit first from a working machine, and then Grid and wire (new and original)...."Ghost"appears anyway...

[Codex]

Re: Mp 9000 random smudge... I'm gone mad!

What kind of room is it?
Is there a working ventilation system or not at all?
How often is the air turned over in that room?
I think that the room has no ventilation at all, and that the only ventilation is done by opening the door ...
The less this door is opened the more moisture fills the air and v.v.

The machine is situated in a Copyshop in Messina (Sicily),the problem starts last winter and till now it's not solved, so i think it's not a temperature problem, the shop is ventilated because the customer leaves the door open summer and Winter...there is an airflow in the shop and the machine is not attached to a wall, there are 15cm of space behind the machine, the filter was cleaned during a PM,in the shop are 7 other machines (Aficio 2075 and one MP 5500 and one MP 7500) no other machine has similar problems.

[davel]

Re: Mp 9000 random smudge... I'm gone mad!

Sounds like this print shop needs to update all of it's old machines.