Designjet T520 36" Roll eject issue

[Quicksilver]

When sending a plot, the machine prints 3-4 inches of data then cancels the job with the message " Error unloading roll". The machine comes to a stop with the media held in the pinch rollers. If you power off & back on & re-load the roll, it will come to ready. It prints fine from the Multi Tray A4 or A3. So far I've ruled out printer driver, as it also fails from internal prints. I've checked & tested the OOP Sensor, Paper servo motor, cleaned the encoder strip & carriage rail. The firmware is at its latest level.

I have asked them to get a new one, but I'm suspecting its just a dodgy, poor quality roll the customer has bought, as I think it's something to do with tension/weight when it's trying to roll feed? Unless anyone knows any different please?

[Kiran Otter]

Most likely the problem is with the roll and the spindle. If the roll turns independent of the spindle, the printer will think the end of the roll has been reached and try to eject the remaining paper. Try turning the roll while holding the spindle. If you can turn it, that's likely the problem. You can wrap some tape around the fixed end of the spindle to help limit the roll turning without the spindle moving. You may also have the paper turning independent of the roll core, but this is rare.

Kiran

[Quicksilver]

Thanks Kiran, if anything, it's the opposite, but understand your description. The roll fits really tight on the spindle & have tried just giving it a slight bit of space. What's notable though, is when the spindle is being driven & after that 4" of print, there's an obvious bounce back of the roll before it errors. I remember on the T920's there was an issue with the spindle that meant replacing it for a new modified one

[tmw]

I recently had the same problem on the same model. In diags it seemed the OOP sensor worked, then it didn't so I replaced it. Still had the problem. It ended up being that the main board needed replacement.

[Quicksilver]

Thanks TMW