Z5400 carriage collides with right edge of paper near end of roll causing paper jam

[CJ-T790]

I never had this problem with the T790 I just replaced, but this Z5400 seems to have a problem with the carriage colliding with the right edge of the paper on roll1 when the paper gets near the end of the roll, and the paper is curled more than at the start. Is there some solution for this other than sitting there with a ruler holding the paper down for every plot?

[Repairatrooper]

Is this a new or used printer? Is it possible there is a guide missing? Have you tried a different media to see if this is paper related and not a hardware issue with the printer.

[CJ-T790]

I picked this printer up a month ago used and had to replace 2 printheads to get it working. I sat next to it and watched it jam, its the 3rd print head that seems to catch the paper (46lb coated). That is one that I replaced, so it's new, but the black of the black/cyan has been streaking. Probably due to these collisions with the paper. 

I replaced the printhead, and then put it right back in, and it printed the alignment page with no problems, then I sent a map to the printer and had a minor collision that it got past. It seems to collide about an inch and a quarter into the print. Then it was out of paper.

I'm going to try a 45lb roll next and see if it has this problem when it gets down to the last 10 feet or not. Since I have a big order I'm working on, I can find out late next week sometime.

[Craig812]

If it is only happening towards the end of the roll check you have loaded the roll correctly. The curl of the paper should be down.

[CJ-T790]

The paper is loaded correctly, but at the end of the roll it has a lot of downward curl to it. When I replaced the printhead with the same print head I looked at the silver clip that keeps the head jammed up to the right side of the plastic carriage. I bent it a bit so it would have more strength holding the printhead. There is nothing at the top of the printhead to guarantee that it is straight up and down. I took a beer can and cut it up and made a half inch by 3in strip that I folded twice and stuck into the left side of the printhead at the top to make sure that it is not slightly cocked in the carriage. With a new roll of thinner paper I was able to print 3 24x36 sheets, we'll see how it does at the end of the roll. I suspect that the "new" printhead was slightly out of alignment, maybe defective from the factory, who knows. If the problem comes back I'll replace the printhead with a new one again and see if that fixes the problem.

[CJ-T790]

I sent 70ft of print jobs to the printer tonight thinking that I could get to the problem next week with some more prints closer to the end of the roll. After all the jobs were spooled to the printer I went down to look at it's progress. Only one 2x3ft print was done and the machine had a 1.01:10 error, so I rebooted it and restarted the print job. I'll deal with that problem later - probably a bad battery.

I sat there and watched it and on the 3rd print job the right edge of the paper got caught on something and curled up, it eventually snapped free and didn't cause a printhead crash with the paper, but it was easy to see that this was the real problem.

These printers have a paper cutter and it is two parts, a beveled disc dragged by the print carriage, and a steel knife straight edge. The knife is usually flush with the plastic paper guides, but in this case the last 3 inches were a bit off - from zero to a half millimeter. I took two strips of half inch by 2 inch packing tape 2 mills thick and carefully taped them down on the plastic guide and the knife edge. Not sure if the cutter will have a problem with sheering off the excess tape or not, we'll see. I think it has fixed the problem.