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Pocavon
06-10-2016, 04:47 AM
Hi,
I'm fighting a constant skew from Tray 1 only on a 421. I have replaced the feed ,Pickup and Sep rollers. Then I swapped tray 1 with tray 2. I finally replaced the tray 1 feed assembly. Still getting the skew. I have cleaned the paper path and used scotchbright with no change. Any ideas would be welcomed. The paper seems to Lag on the end closest to the user. I noticed this by stopping the copying process right at transfer. The skew is NOT optics related. It occurs on internal test patterns.

habik
06-10-2016, 07:50 AM
What about tray 2 and Bypass? Does it skew as well?
Paper loop adjustment perhaps?
Can you produce some samples of halftone on A3 and take a picture with phone so we can have better idea how bad it is.

Any deformations on the door?


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Pocavon
06-11-2016, 10:25 PM
What about tray 2 and Bypass? Does it skew as well?
Paper loop adjustment perhaps?
Can you produce some samples of halftone on A3 and take a picture with phone so we can have better idea how bad it is.

Any deformations on the door?


Sent from my iDon't believe in marketing device using Tapatalk
Tray 2 feeds fine. I suspected the actual tray 1 cassette but when I put tray 2 paper cassette in the tray 1 area , I get the same skew. I'm trying to get an idea as to what is the same and what is different before the paper reaches the registration area. And the bypass doesn't work either. It has a bad motor , I think. I hadn't considered the buckle loop adjustment being that Tray 2 feeds almost perfect. I have been troubleshooting possibilities related to the tray 1 area only.

Iowatech
06-11-2016, 11:19 PM
This could be just so much nonsense, as I've only worked on analog Konicas. As such, I apologize in advance.
Still, have you checked the paper in the tray for defects? I've seen something like this being caused by like ten or so pages at the bottom of the stack having a corner turned under. It's kind of hard to see, for me anyway, so it can be kind of easy to miss.
Something else that makes the paper in that tray not parallel to the pick up roller could be causing this too.

Pocavon
06-12-2016, 05:33 PM
This could be just so much nonsense, as I've only worked on analog Konicas. As such, I apologize in advance.
Still, have you checked the paper in the tray for defects? I've seen something like this being caused by like ten or so pages at the bottom of the stack having a corner turned under. It's kind of hard to see, for me anyway, so it can be kind of easy to miss.
Something else that makes the paper in that tray not parallel to the pick up roller could be causing this too.
Paper was my first suspect , So I loaded fresh stack, Also I swapped tray 1 with Tray 2

Pocavon
06-14-2016, 12:17 AM
Tray 2 feeds fine. I suspected the actual tray 1 cassette but when I put tray 2 paper cassette in the tray 1 area , I get the same skew. I'm trying to get an idea as to what is the same and what is different before the paper reaches the registration area. And the bypass doesn't work either. It has a bad motor , I think. I hadn't considered the buckle loop adjustment being that Tray 2 feeds almost perfect. I have been troubleshooting possibilities related to the tray 1 area only.
Thanks to all for your input. I went back to this skew issue this morning , What I found was ....There is a silver tension spring that rides OVER the registration bushings on either end of the reg roller. Well ,on the outboard side(closest to user) the spring had slipped off the bushing and was riding on the shaft itself...Causing drag on that side. I thank you all for alleviating me of my tunnel vision. I was focused on the tray area and not the registration area.

habik
06-14-2016, 06:04 AM
Well done!
You would have thought the skew will happen all the time from all trays. Peculiar.
I wonder how it came off. Spring sits on top of bushing which should have a lip, so it wont come off.


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Pocavon
06-15-2016, 12:36 AM
[QUOTE=habik;520712]Well done!
You would have thought the skew will happen all the time from all trays. Peculiar.
I wonder how it came off. Spring sits on top of bushing which should have a lip, so it wont come off.
That was exactly my thought process. Why did tray 2 feed correctly? It wasn't until I notice this sites advice was directed toward registration that I even looked at registration as a source. Once I started to focus on The registration, I found the bushing issue in about 10 minutes.

Thanks again,

Pocavon
06-15-2016, 12:37 AM
Well done!
You would have thought the skew will happen all the time from all trays. Peculiar.
I wonder how it came off. Spring sits on top of bushing which should have a lip, so it wont come off.


Sent from my iDon't believe in marketing device using Tapatalk
That was exactly my thought process. Why did tray 2 feed correctly? It wasn't until I notice this sites advice was directed toward registration that I even looked at registration as a source. Once I started to focus on The registration, I found the bushing issue in about 10 minutes.

Thanks again,

Downunder
06-15-2016, 09:04 AM
That was exactly my thought process. Why did tray 2 feed correctly? It wasn't until I notice this sites advice was directed toward registration that I even looked at registration as a source. Once I started to focus on The registration, I found the bushing issue in about 10 minutes.

Thanks again,

The reason it was only skewing from tray 1 is because when it feeds it has a tighter bend to travel through before entering into the grey registration roller. The other trays which when fed, travel up the vertical being driven by the forwarding rollers.

Yes sometimes we need to stand back and refocus before we charge into the fault. Well done.

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