This is probably old news to many of you, but I found out some interesting information concerning printer jams last week.

We have five printers in my office, two of them pretty high-end color laser printers, the others just regular black and white workhorses. (The Kyocera is well on its way to the million page mark now...)

In recent weeks, we've been experiencing printer jams on printers that normally just don't do that. The Kyocera, in particular, would run for months and tens of thousands of copies at a time between jams. Suddenly, we were experiencing three, four, even five paper jams a day. The big HP color laser printer jammed so badly we had to call the repair service to come in and take it apart.

I asked the repairman what was going on, and he said, "Watch this." He took a half-inch stack of paper out of the feed tray and laid it on a flat desktop. "Now, crouch down and sight along the edge of the desk," he said. And lo and behold, that stack was curled up slightly at each end -- no more than a millimeter or two. "That's enough to cause printer jams," he said.

He told us how paper comes from the paper mill in huge rolls. The high-end paper comes off the outside of the roll where the curvature is minimal. The cheap stuff comes off closer to the hub, where the curvature is greater.

We called the office supply store to come and take their cheap paper back and replaced it with our normal paper (they had been out of that paper before, which is how we got stuck with the cheap stuff in the first place) and there has not been a single printer jam anywhere in the building since.

The service call cost us $100, which in my mind was money well spent.

tanstaafl.

That's just a little more than just worth knowing, and I thank you,, if you can also sort out why sticky labels, that my HP printer should cope with doesn't, I have the whole picture!

Related to this, many people also seem unaware that printers have a preferred side up when loading the paper, based on the curl. Higher end papers often label the wrapper with an arrow indicating the side which should be inserted face up.

Cheers

Thanks for actually believing the repair person. I have to tell that to people all the time and many times they refuse to believe it. I have found many times loading the paper with the curve up so it lays flat in the tray solves the problem.

Yes you want the curled ends down so the weight of the stack ends up making the paper lay flat in the tray.

Thanks for the tip. I've also been told that humidity change can cause the paper to curl that slight bit.

Side note: The Kyocera-Mita 6330 copier/printer/scanner at my office has clocked over 650k pages in its two years so far. It's had about 1/100000th as many jams. (watch me have done that math wrong...) Shame on HP for making us change imaging drum with toner after 3,000 pages when my Kyocera-Mita drum lasted 500,000 pages.

Ahh, this is so true. I used to be a printer by trade, and believe me., I learned more about paper than I ever wanted to.

Where you aware that paper has a grain? Cut a large square sheet and hold it by your fingertips in the center. Now turn the paper 90 degrees and do it again. One way will flex more than the other. Paper will feed through a press and printer better if it's with the grain. This is not an issue usually with 8.5x11 as the parent sheets can be cut evenly with the paper all facing the same direction. Parent sheets are usually 23 by 35 inches.This allows for 8 sets of paper cut with VERY little waste. 8.5 x 14, on the other hand, will only allow four sets cut with the grain and one set cut against the grain. This means that 20% of the legal paper you feed through the printer will curl more than the other 80%. This can be a HUGE difference in terms of how paper will feed through a press. I have, as much as I hate to admit it, thrown away over 400 sheets of legal at a time (when I say threw away, I mean made into non-printed material, like note pads and such). It simply wasn't worth my time to try and force it through the press. I spent more time cleaning out the press than I did actually printing. It became a cost saving deal.

Inks are something else people are rarely aware of. Blue is much more difficult to run than red as the blue is a much lighter ink. The tolerances for a good run are FAR narrower for blues. the only thing worse is gold ink. Royal PITA.

Also, when working with non-metal plates (most of the time for runs less than 20,000) your results will be MUCH better if your original was printed at around 300-450 DPI, rather than 600 or higher. The dots are just to small at high resolutions for the plate material to pick up. If you want to try a quick test to see what I'm talking about, print a picture in greyscale on a laser at 600 DPI and then photocopy it. Now do the same only printing at 300. Which one comes out better? Check printers use this phenomena all the time. The background is printed at 300DPI with the exception of a pattern that spells out VOID printed at 600DPI. When photocopied, the word VOID can clearly be seen all over the copy, whereas with your eyes, it's hard to see the difference.