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Valintine
08-02-2019, 05:56 AM
Hello

I am a tech that usually works on Toshiba. The boss brought in a 1250p that had some cq issues. I replaced the worn drum developer & transfer belt. On dark images I still had some banding. I thought it might be the LPH. I cleaned it with a damp cloth hoping for the best & the banding changed. If this is acting up does it mean it’s shot or is there an adjustment or way to clean it that could save it.

Thank yiu you in advance for any help.

allan
08-02-2019, 07:43 AM
Post a sample.

The LPH is a real pricey bit of kit.
Did you replace the cleaning blades?
The developer and drum normally needs to be replaced at the same time.

Valintine
08-02-2019, 11:04 AM
Yes I did. After the drum & developer I saw lines or banding. I took out the lph cleaned it & the issue was still there but different. I am pretty confidant this is causing the issue.

blackcat4866
08-03-2019, 01:33 AM
It's a fairly common failure item. I've replaced four LED arrays on four separate machines, each over 5M images. The image fault is pretty bizarre: If you print or copy an image LTR you'll see the part of the image at the bottom of the page will be repeated 3 or four times in bands UP the page, some of them negatives, kind of like a poor drum cleaning issue but crossfeed. If you re-boot the machine it will go away for a while, maybe a week the first time, then two days the second time, more and more frequently until it's doing it all the time. You don't get the whole assembly, so take care shifting the new array onto the metal backing plate. On the first one I tried the cable first (based on cost), and it didn't help.

Just on a side note, you should change the primary charge wires, grid, discharge wire, and check the web ... minimum. =^..^=

Valintine
08-05-2019, 03:46 PM
Sorry for the delay in replying I was out on Friday. I stopped by the office on the way out of town and the banding had gone away. It seems it recovered from being cleaned.

We are trying to convert this machine to print with the micr toner so they can print checks. I was told on a previous post all i should need to do was change the toner and run a lot of copies. I replaced the drum developer and transfer belt due to them being shot and we put in the micr toner. We did have a small issue with the hopper and ended up needing to put the micr toner into the old toner bottle.
At this point the check reader is reading the micr toner but I am getting a background that looks like an issue with bias. When replacing the developer I followed all the steps in the service manual. There is an issue on the lead edge and a definite background. Any feedback would be greatly appreciated.
4328643287
When I scanned the sheets you could not see the issue. I am attaching close up pictures of a check and the meter report.

Valintine
08-05-2019, 05:49 PM
I have cleaned the transfer roller under the transfer belt and ran a ton of prints. The lead edge looks almost completly cleared up but I am still seeing some background. Any thoughts?

Thank you in advance for any help.

blackcat4866
08-05-2019, 11:51 PM
Somehow I did not imagine you dumping out the KM toner and spooning MICR toner into the old bottles. Which toner manufacturer advocates this method? I doubt that it's KM. Did you do any of the Drum Peculiarity adjustments after your developer change? What about those charge wires and grid?

It's perfectly alright for you to ignore my questions ... but I won't ask again. =^..^=

allan
08-06-2019, 11:43 AM
And the LPH issue?
If the cleaning blades fail the correction patches starts showing up making cross feed bands about a half inch wide.
Those samples looks over toned. I would block off the intermediate hopper from feeding toner to the devtank then run half-tones to lighten it up.
Then reinitialize the developer. I Know nothing about that toner and could be the issue itself.

The TCR with normal and that toner could be different...

Valintine
08-06-2019, 02:26 PM
Blackcat
I was out the when the toner came in. My shop tech was able to pop the compression cap off of both bottles and dump out the old original toner and fill the micr toner. I was told it was a mess but once they did that and ran prints the check scanner started recognizing the micr toner.

I followed all the steps in the manual as far as drum Peculiarity adjustments after changing the developer. I did clean the charge wires housing and grid when I did the developer change and again yesterday. After cleaning yesterday the background did get worse. I have ordered the charge assy hopefully it will be in this morning.

Allan
I am not sure about the LPH being bad or not but with the high cost the boss does not want me to order it without being 100% sure that it is an issue. I do not see any signs of the blade failing at this time. I am going to follow your instructions about toning the mix down as soon as I finish posting this post.

Thank you both for your answers.

Valintine
08-06-2019, 03:13 PM
Hello

I have blocked the hole for the intermediate hopper from feeding toner and ran the test prints. I am noticing that the void edges are not as void as I would expect them to be. Do you think this could be a result of over toning also or something else?

Valintine
08-06-2019, 08:10 PM
Hello

After almost 24 hours the prints returned to what they looked like before cleaning the charge assy.

I toned down the machine and reran the developer set up and not I shill have the background and the print is very light. I am attaching to samples. For some reason the print on the meter sheet came out a lot darker than it is on the actual sheet. I have ordered the charge assy. Any thoughts on if I am going down the correct path would be appreciated.
4329943300

allan
08-06-2019, 09:16 PM
So not over-toning please undo that tweak by adding toner spoon by spoon then initializing only after fixing your background issue.
Try development bias adjust or charge voltage manual adjust.
Now the manual states that these settings should not be adjusted in the field.
You need to move the image creating band or widen it but separating the drum charge and development bias.
But i could lead you in the wrong direction so please the setting values to return them is you don't get joy.

This is heavy tweaking and yea just checked the manual states not to mess with it. "Not to be conducted in the field".

You will find both those adjustable setting under Process adjustment in service mode.

If you have a good developer tank with normal toner in it test is to give you faith that the machine is not the problem but the toner is.

Do you know if this has been done before?

The discharge wire there?

Valintine
08-27-2019, 03:47 PM
Is there a trick to get into the developer bias? When I have it up on the screen the selection is grayed out and I am not able to make any adjustments.

Valintine
08-27-2019, 04:13 PM
Sorry I hit submit before finishing my post.

Everything is new drum charge discharge lph developer transfer belt ect. Prints are fine before changing the toner.

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