P8000 stretching prints vertically on cut-sheets

[ChrisTBL]

We have several P8000's that we print on to thick cut sheets with (1.5mm). One of the units has started stretching the prints vertically. We believe the cause of this is the pressure rollers not pressing down hard enough, so the sheet is "slipping" through the rollers on the way down, causing the prints to be off by 3-4%. So our 24" tall prints are coming out 25" tall.

The reason we think the rollers are the culprit is because when we load the sheets the are normally held in by the pressure of the rollers, but on the troublesome printer they simply slide right through if we let go of the sheet. Once we press the "load paper" button the rollers clamp down and it will hold the paper but it seems like the amount of pressure is not enough for correctly sized prints.

We've been tearing our hair out over this for weeks. Any help would be greatly appreciated!

[KeithR]

Can't give a definitve answer, but I noticed difference on an image I printed a couple of months ago. The image appeared shorter on the paper than what I had sized it in software. I rechecked my settings and nothing was amiss. I decided to make a smaller sized test print on a cut down sheet so I quartered the sheet (17x22) to 8.5 x 11. However upon measuring the sheet (from Canson) it was about 1-1/4 inch longer & about 3/4 inch wider than what the box indicated. A quick back & forth email to Canson and I was sent a replacement box.

[ChrisTBL]

Thanks for the reply KeithR. We've been measuring the print directly and comparing to our other workin units so this is not an issue of sheet size.  We have been bit by that in the past too though!

[dgberg]

We have a couple of 8000's as well. Have you tried another one of the 3 vacuum settings?

[ChrisTBL]

Dan, thanks for the tip but it doesn't seem to have an effect. Our cut sheets are quite thick so the force of the vacuum at any setting doesn't seem to affect how it feeds. The spring-loaded rollers are what keeps it feeding properly when it works, and in this case they don't seem to be applying as much downforce but we're not sure why.

[mcbroomf]

On one of my old/very early 17" Epson printers the rollers ended up getting something on them from the paper and stopped loading properly.  This wasn't the feed rollers, but the pickup rollers taking the paper from the tray, so I had to manually load paper one print at a time.

You might try cleaning the rollers carefully to see if the slip is due to rag/paper debris on the rollers rather than spring pressure.