eco p3150 continuing image quality problem

[Rainer]

Re: eco p3150 continuing image quality problem

Weird, but at least it's working.

For me the case has cleared up:

In general, these devices are sensitive to moisture in the paper. The effect that can be seen in the photos is called the "Obiki effect" at Kyocera. It is created by the water evaporating in the fuser unit, which "blows" the toner off before it is fused.

This is also the reason why the service manual specifies a humidity of 36 to 65% for printing with optimal quality, although the printer itself is specified up to 80%.

In my case, two things came together: On the one hand, the paper was "at the limit" with up to (or more?) 65% moisture, on the other hand the firmware was out of date, and Kyocera still carried out some optimizations here.

It is also clear: If the paper is (too) moist, the greater the fusing temperature, the greater the effect.

PS: (Factory default ist "normal 2" for plain paper).

[PrintWhisperer]

Re: eco p3150 continuing image quality problem

For me the case has cleared up:

In general, these devices are sensitive to moisture in the paper. The effect that can be seen in the photos is called the "Obiki effect" at Kyocera. It is created by the water evaporating in the fuser unit, which "blows" the toner off before it is fused.

This is also the reason why the service manual specifies a humidity of 36 to 65% for printing with optimal quality, although the printer itself is specified up to 80%.

In my case, two things came together: On the one hand, the paper was "at the limit" with up to (or more?) 65% moisture, on the other hand the firmware was out of date, and Kyocera still carried out some optimizations here.

It is also clear: If the paper is (too) moist, the greater the fusing temperature, the greater the effect.

PS: (Factory default ist "normal 2" for plain paper).

Great observation on the moisture content, what device did you use to measure it? I have been looking into the standard 'Wood/Paper' moisture meter with 2 electrodes (resistive) but they start pretty cheap and I wonder at their accuracy.

I'm not sure I agree with the 'water vapor outgassing' theory as the effect is a bit too directional and 'fine-lined'. Moisture induced micro-arc would seem more apt.

Has anyone done a panic stop in between transfer and fuser to see if the effect is fuser induced?

[Rainer]

Re: eco p3150 continuing image quality problem

Great observation on the moisture content, what device did you use to measure it? I have been looking into the standard 'Wood/Paper' moisture meter with 2 electrodes (resistive) but they start pretty cheap and I wonder at their accuracy.

I do not measure the moisture from the paper itself but the moisture in the air (with an electronic measuring device, uncalibrated). And here I can make the observation that exactly corresponds to the statements made by Kyocera in the service-manual: If the humidity rises to 65% (or above), "quality losses" can be seen on the printouts. (There is a delay in this, because with increasing humidity the paper takes a while to also become more humid).

And vice versa, the printouts are okay if the humidity is well below 65%.

[PrintWhisperer]

Re: eco p3150 continuing image quality problem

I do not measure the moisture from the paper itself but the moisture in the air (with an electronic measuring device, uncalibrated). And here I can make the observation that exactly corresponds to the statements made by Kyocera in the service-manual: If the humidity rises to 65% (or above), "quality losses" can be seen on the printouts. (There is a delay in this, because with increasing humidity the paper takes a while to also become more humid).

And vice versa, the printouts are okay if the humidity is well below 65%.

Good to know. The SM comments are more along the lines of atmospheric effects where humidity effects charging and DV bias. They (japanese engineers) generally don't get that specific on paper moisture content, expect paper is sold in moisture proof wrappers, and even provide plastic zip-lock bags for storing partially opened reams....not that any customers use them

However with the new Ink-jet machines from Kyocera, moisture and curl are critical factors so I am trying to assess using a meter to actually measure the paper's mositure content.

[Drivee]

Re: eco p3150 continuing image quality problem

I think that this is air bubble in toner. When pressure roller and fuser start to bake toner, it explode and push toner out from line.

[Rainer]

Re: eco p3150 continuing image quality problem

I think that this is air bubble in toner. When pressure roller and fuser start to bake toner, it explode and push toner out from line.

You mean, if you succeed in ordering "air-bubble-free toner", there is no effect? I think it clearly has to do with the moisture, which can also be observed well. (no effect at i.g. 60%, effect there if 65% or more ...). The kyocera support has also confirmed this behavior and it is documented in the service manual.

[Drivee]

Re: eco p3150 continuing image quality problem

Good to know.

I have some cartridges which give me same effect. Change cartridge that problem disappear. Only difference between cartridges is a toner.

[Rainer]

Re: eco p3150 continuing image quality problem

Change cartridge that problem disappear.

Well, nothing can change immediately after changing the toner, because it takes a while for the new one to get onto the paper via the developer unit ... Could it be a coincidence that the humidity changed after the toner was changed?

[Drivee]

Re: eco p3150 continuing image quality problem

I know that, I need 300 pages to reach new toner. Depend of coverage. Humidity is same, as I am in toner recycle business, I did talk with Japan about that problem. Their explanation is air bubble.... However, I am 100% sure about it, they will sometimes talk to me kids stories. I mean, for Kyocera, most easy way is to point finger on end customer and printing environment. Imagine that they say: We bay bad toner and settings of printer sometimes need to be changed.

I think that in this cause.. only toner from DEV section is bad.

[Rainer]

Re: eco p3150 continuing image quality problem

Maybe the effects are different. I have observed this moisture-dependent effect on two p3145 machines, with completely different serial numbers and production periods. I think it is unlikely that the original toner supplied with both devices will be bad ...

[Drivee]

Re: eco p3150 continuing image quality problem

And you print with both machines +500 pages?

[Rainer]

Re: eco p3150 continuing image quality problem

yes, 1500 and 3000 pages, each with the original toner supplied. The production period of the two machines is about 1 year apart.