C452 imaging unit

[yianni]

How much is the distance between the magnetic developer roller and the OPC?
There is a magenta IU which always consumes the developer powder in a few hundreds of prints. I suspect the above distance.
I know that most of you would replace the IU. But I'm living in a country with lower mean income, so to rebuild some consumables (iu, drum, fuser) is more frequent case.

[blackcat4866]

Re: C452 imaging unit

It's usually a primary charge issue that causes the developer to pull. I have to assume that you have a source for developer/starter. Do you have a source for primary charge wires and grids also? =^..^=

[yianni]

Re: C452 imaging unit

To say the truth, I didn't think the primary charge as the part causing the problem.
The technician told me also about the primary charge. I'm not a technician. You confirmed this. I haven't face this problem before. Thank you for this information.
I see there aren't new compatible charge grids or the whole primary charge as parts. There are sold used ones. There are new compatible ones only for newer models.
Btw, do you know the distance between developer roller and OPC? I should adjust this distance too.

[blackcat4866]

Re: C452 imaging unit

Since these image units are sold as an assembly, the manual does not go into detail about internal adjustments. =^..^=

[copyman]

Re: C452 imaging unit

try rebuilding drum unit with new grid & sawtooth. put new developer in and should help. Personally I've had good experience with rebuilding drum units but not developer. developer always dumped.

[yianni]

Re: C452 imaging unit

I changed the developer. It ate the developer three times.

[copyman]

Re: C452 imaging unit

It's eating developer because drum and/or grid & sawtooth are over life and shorting out.

[AjitN]

Re: C452 imaging unit

To say the truth, I didn't think the primary charge as the part causing the problem.
The technician told me also about the primary charge. I'm not a technician. You confirmed this. I haven't face this problem before. Thank you for this information.
I see there aren't new compatible charge grids or the whole primary charge as parts. There are sold used ones. There are new compatible ones only for newer models.
Btw, do you know the distance between developer roller and OPC? I should adjust this distance too.

You can try to exchange Magenta Unit with another, say Yellow unit (Drum unit parts only, one by one)
This will confirm & isolate the problem either Drum size OR Charge Unit. I don't think you can modify the gap between drum & mag roll. Maximum you can adjust is Trim Bar which controls amount of developer on Mag Roll, reduce the gap so less developer on mag roll.
This will affect CQ, magenta density will be less, so instead try to isolate the problem first.
Hope this helps

[yianni]

Re: C452 imaging unit

The imaging unit has two screws (at the two sides) that adjust the distance between the developer section and the drum section.
Someone can put a cardboard between the developer roller and the OPC and measure this distance. I don't have another imaging unit for measuring this distance. For example, I put a 150g paper and I adjusted the distance. I think it is low, may it needs a 500g cardboard or a 1mm filler.

[darry1322]

Re: C452 imaging unit

C452 color units are single units. Drum and developer sections together.

If you want to check distance measure the gap on your yellow or cyan units and compare.

[tsbservice]

Re: C452 imaging unit

yianni, you need thickness gauge (aka Doctor-sleeve jig) not paper or cardboard to measure the gap. As previous post suggested you can use other unit to measure. The you can narrow the gap maybe 10%.

[copyman]

Re: C452 imaging unit

It's not the gap between the drum and developer. I will say for the last time it is the drum or corona. Of course if you messed with the distance then you will have to put back where it was. Good luck

[AjitN]

Re: C452 imaging unit

The imaging unit has two screws (at the two sides) that adjust the distance between the developer section and the drum section.
Someone can put a cardboard between the developer roller and the OPC and measure this distance. I don't have another imaging unit for measuring this distance. For example, I put a 150g paper and I adjusted the distance. I think it is low, may it needs a 500g cardboard or a 1mm filler.

R U sure that we can adjust gap between Drum & developer (mag roll) unit?
We can make it loose but adjusting GAP?
I am really unaware for that. Please let me know in detail as aftermarket drums do not have consistency in Drum size(Diameter).
If it is possible, we can easily use aftermarket spares & save money.

[yianni]

Re: C452 imaging unit

It's not the gap between the drum and developer. I will say for the last time it is the drum or corona.

Of course, I understand this.

> Of course if you messed with the distance then you will have to put back where it was.

Now, it's a mess. A technician went to fix it. Today the customer told me the technician tried to correct the gap and fix the other two IU (cyan and yellow) which they are loosing the developer too now. Cyan and yellow worked well.

R U sure that we can adjust gap between Drum & developer (mag roll) unit?

Yes, for sure. At the sides there is a screw different in shape than all the other screws (one is shown with the red arrow). It needs first to loose two other screws which keep the same metal in place.