Xerox 800/1000 yellow toner problems

[MIE]

Im looking for a bit of technical assistance here. Since acquiring my refurbished Xerox 800, I have had problems with the yellow toner coverage. Within 20,000 impression the yellow toner goes out dramatically. I have had technicians say it environmental, so I have adjusted room temperatures to accommodate each time I have been given an operating temperature.

To give you an idea

Temp 23.7 C to 26.9 variance over an 8 week period
R humidity 27% to 36% over the same period.

I have a meter which tracks the temp and relative humidity in the space. All measurements are within the specs according to the operator’s manual. Tech specialist advised 22 degrees C so this was the range for the next 2 days.

Temp 21.7 C to 22.3 variance
R humidity 27% to 31%

I was told that the printer was to be set to system default for inboard / outboard and only the charge corotrons and drums should be changed if the colour went out again. It took 2 days to go out and the technician came and changed the drum and coros again. The photos attached show the result. The darker sheet was the original run after the tech spec adjusted and the lighter when a new drum and coro was changed 3 days later.

My concern is, that for 3 years this problem has been occurring and that it only ever effects the yellow toner. It always gets heavier at the side of the sheet and eventually I have low levels of yellow toner in the centre of the page. What else could be causing this, other than the environmental conditions advised by the tech specialist.

Also, after speaking with a number of print owners who have the same machine without the problem that I have, we are concerned that the temperature and relative humidity tolerance is not as broad as we were led to believe when we acquired the machines. If the xerox 800/1000 are as intolerant of temperature changes that I have stated above, then how can a print business be expected to keep the temperature within such a fine scope without having imaging problems.

I asked a mechanical engineer to come and take a look and advise about how to best manage the environmental conditions to meet the 22 degree stable temperature the technician said was required to guarantee stable colour, and he said due to the heat that the device outputs, a constant 22 degree temperature would be impossible unless I wanted to spend more than the machine was worth install a system that would still be unable to supply a constant level of 22 degrees.

Any advice would be welcome as to whether another underlying problem could be causing this issue.

 

[Milo Wilson]

I don't believe that it has anything to do with environment. I would lean towards the dev. Density sensor then run a progen setup.

 

[MIE]

Thank you Milo... I will pass this on. I have had dev tanks etc changed to fix the problem, however, i believe it is something other than environmental. The problem has been with the machine for 3 years and i am unable to ever print a job twice with any degree of colour accuracy / matching if yellow is involved.

 

[Possumgal]

I'd agree with Milo. Temperature and humidity do play a part, but not to this extent, not with always the one color, and certainly not with the unevenness you've shown. The techs are probably using this as an excuse.

 

[DYP]

Have you eliminated the ROS getting toner dust on it, or light getting into the machine where the yellow drum is.

What sensor system does the printer have for maintaining uniform density?

 

[MIE]

Unfortunately some tech always go with some form of owner related issue as an excuse. Ive been operating Xerox machines for over 30 years and I have never seen this. If it were every colour and the temp and RH were from one end of the scale to another, I might be seeing some changes in colour, however, not like this.

 

[PrintingFools]

Im looking for a bit of technical assistance here. Since acquiring my refurbished Xerox 800, I have had problems with the yellow toner coverage. Within 20,000 impression the yellow toner goes out dramatically. I have had technicians say it environmental, so I have adjusted room temperatures to accommodate each time I have been given an operating temperature.

To give you an idea

Temp 23.7 C to 26.9 variance over an 8 week period
R humidity 27% to 36% over the same period.

I have a meter which tracks the temp and relative humidity in the space. All measurements are within the specs according to the operator’s manual. Tech specialist advised 22 degrees C so this was the range for the next 2 days.

Temp 21.7 C to 22.3 variance
R humidity 27% to 31%

I was told that the printer was to be set to system default for inboard / outboard and only the charge corotrons and drums should be changed if the colour went out again. It took 2 days to go out and the technician came and changed the drum and coros again. The photos attached show the result. The darker sheet was the original run after the tech spec adjusted and the lighter when a new drum and coro was changed 3 days later.

My concern is, that for 3 years this problem has been occurring and that it only ever effects the yellow toner. It always gets heavier at the side of the sheet and eventually I have low levels of yellow toner in the centre of the page. What else could be causing this, other than the environmental conditions advised by the tech specialist.

Also, after speaking with a number of print owners who have the same machine without the problem that I have, we are concerned that the temperature and relative humidity tolerance is not as broad as we were led to believe when we acquired the machines. If the xerox 800/1000 are as intolerant of temperature changes that I have stated above, then how can a print business be expected to keep the temperature within such a fine scope without having imaging problems.

I asked a mechanical engineer to come and take a look and advise about how to best manage the environmental conditions to meet the 22 degree stable temperature the technician said was required to guarantee stable colour, and he said due to the heat that the device outputs, a constant 22 degree temperature would be impossible unless I wanted to spend more than the machine was worth install a system that would still be unable to supply a constant level of 22 degrees.

Any advice would be welcome as to whether another underlying problem could be causing this issue.

Forgive me if I asked basic questions.
As I don’t know how far you’ve gone down the rabbit hole yet in trying to repair this issue.

My first question would be if you’ve worked on the
Bias Settings yet ?
"Bias Transfer Roll "
This deals with static electricity.
We often have to adjust this on our machines.

A lot of times the static in the air can affect your prints daily.
Static charge build-up is enhanced by different weather conditions.
Dry air has a different charge from humid air and so on......
When you have something set up perfectly on Monday and you come in Tuesday and everything is changed that’s because the natural static in the air has changed.
This can even change within the same day.

If you do have a luck by adjusting the bias settings then the next step would be to control the environment for static in the air.
I would ask if you have a large rollup door with in the same room as machine.
Or even a small door that the employees use often , that leads to outside.
This can cause problems.

if you have already tried the bias settings
then I would ask if the yellow developer housing has been replaced?

I guess depending on these answers, I would have more questions.

 

[MIE]

Forgive me if I asked basic questions.
As I don’t know how far you’ve gone down the rabbit hole yet in trying to repair this issue.

My first question would be if you’ve worked on the
Bias Settings yet ?
"Bias Transfer Roll "
This deals with static electricity.
We often have to adjust this on our machines.

A lot of times the static in the air can affect your prints daily.
Static charge build-up is enhanced by different weather conditions.
Dry air has a different charge from humid air and so on......
When you have something set up perfectly on Monday and you come in Tuesday and everything is changed that’s because the natural static in the air has changed.
This can even change within the same day.

If you do have a luck by adjusting the bias settings then the next step would be to control the environment for static in the air.
I would ask if you have a large rollup door with in the same room as machine.
Or even a small door that the employees use often , that leads to outside.
This can cause problems.

if you have already tried the bias settings
then I would ask if the yellow developer housing has been replaced?

I guess depending on these answers, I would have more questions.

Thanks for the reply

The 2nd bias is adjusted if needed. Overall the other colours are good and dont usually have a problem. We have tried every possible level in regards to humidity over the past 3 years. No impact on the problem. I have had a tech spec here yesterday and for the first time ever, we now have the problem in magenta and not yellow. I dont know what went on there.

 

[PrintIT]

We've had two Colorpress 1000s go through New England winters with no humidification and never had any problems like that. We'd burn through cleaning units and BTB's much faster, but no quality issues like that. We added a humidification system this past year because we added an iGen, and that absolutely needs the humidity.

We went through two years with no added humidity and temps bouncing probably 10 degrees throughout the day and both Colorpress's ran great.

You say you've been fighting this for 3 years, I would have let the techs fight with it for a few months, then I would have been screaming at my sales rep to start the replacement process under their total satisfaction guarantee.

 

[PricelineNegotiator]

You say you've been fighting this for 3 years, I would have let the techs fight with it for a few months, then I would have been screaming at my sales rep to start the replacement process under their total satisfaction guarantee.

This is a refurbished model, he may not be able to exercise that. If all of the above is true, then he should of course shoot for it, if it is an option.