Lead Edge and Trail Edge - Banding...?

Hi there guys,

I've been running into this issue from time to time.

Usually it's only on one edge and usually this is mostly a problem on the XL sheet size.

However I've been encountering this on SRA3 as of late too.

It is most apparent on darker halftones.

My current solution is to run less images up on a sheet and the usual nudging and less gutters for bleed.

But wanted to know if there is an actual fix to this as it shouldn't be occurring with the regular sheet size.

I'm aware that on the XL size when this issue occurs the techs put it down to 'Belt vibration' in where they recommend putting a colour bar on the lead edge and trail edge of the sheet to help alleviate this.

Could anyone share a fix or solution to this? Machine is running great otherwise.

It's not a wiremod. I was thinking something to do with the spot blade but it's relatively new and it's still been doing this between service intervals.

See picture.

 

Hmm... Haven't seen this on my machine before. So here are some shots in the dark...

Are you running with an ATA? Does turning it on or off make any difference?

If you lower the voltage running through your transfer/detack for the stock does it make any difference?

If you cheat the doors for area 3 and area 5a/b do you notice any kind of buckling on the sheet as it either enters or exits the fuser?

 

Hello from swiss..... is your job 1 or 2 site printet?... try to print only 1 side at time... wat kinde of paper you use?...

 

....fuser roll look ok??

 

Those are streaks not banding Multiple suspects. Fuser roll worn, STAB worn, PRB contaminated, dirty CPUC, Recharge Corotron, Charge corotrons and grid, pre transfer and grid, worn or cleaner contaminated flicker bars/brush, dev tank donor rolls or toner build up behind them, worn fuser meterblade causing excess oil to sit at that point

 

Aren't streaks process-direction? That looks cross-process...

 

[x]Fuser roll is fine
[x]Tab blade is fine
[x]PR Belt is fine
[x]Coros/Grids all good, recent replace.
[x] In this job it was happening on 1 sided and 2 sided. Made no difference.
I've actually changed everything in the machine besides the dev tank rolls.
Initially my cyan was spitting too frequently so i reduced the toner concentration from 5.5 down to 4 and it fixed the problem suggesting that it is likely those rollers.

It wasn't that long ago that the pressure roller/ram assemly was changed.

Anyway... currently just 'dealing' with it by re-orientating artwork. or less up on a sheet.

It happens on the short edge. Inboard to outboard. Parallel with fuser direction to the other gents that questioned.
Hence why i said banding

 

That is definitely a banding issue not streak. There might be an issue with prefuser transport speed. The speed of the prefuser transport in relation to PR belt speed is usually the culprit.

 

This looks like tail edge flick. Where the tail edge bends up and hits the PR belt as it moves under the imaging unit.

First try flipping your paper over. If that doesn't help adjust the TAB blade height.

 

not a pr belt issue?

 

Flipping paper doesn't solve it. I've done more complicated things but never adjusted tab blade height. Got a guide for it?

It's not the PR belt. Belt is in good nick. Has happened over a few belts. It happens on every sheet so not belt.

 

There's a way to adjust the prefuser transport speed in relation to PR belt speed. Have you looked at the paper buckle where the paper is detacking from the PR belt and the pr belt fingers?

 

Not the greatest image but beneath the blade (circled red) there's an adjuster with a single silver torx head bolt. Undo that then by hand just tilt that adjuster manually either left or right and you'll be able to see the TAB blade elevate or lower.