Broken laser printer prints full bleed, fixed printer has margins, why?

Like most printers, mine has minimum margins. My driver knows about them, and if I try to override them then the printer seems to enforce them. This seemed completely normal to me until my printer developed a defect that led to one color always being turned on, so everything I printed came out normal except for also having a background of that color. What confused me is that the defective color printed across the whole page, with no margin. Why can't the printer do that intentionally in normal circumstances?

Specifically, I have an HP Color LaserJet 3800, but I expect this question to apply to a lot of laser printers. The defect in question was a lack of high voltage to one of the toner cartridges, leading to it depositing toner evenly across the whole page.

Sparr

Posted 2014-12-28T20:33:37.883

Reputation: 911

Without knowing the nature of the defect or the manufacturing specs for the printer, people are just going to be guessing as to what might be going on. – fixer1234 – 2014-12-28T23:29:46.653

Who says the printer can not have 0 margins? It depends on driver, which could obviously be different than what it is. – kreemoweet – 2014-12-28T23:35:39.343

You wouldn't want toner missing the edge of the page , and getting on the rollers and transfer belt over and over again. It is likely that margins/borders exist to cover for a bit of slop and squew , and have all the toner landing where it should, when it was failing it was not doing anything like it should :-) On ink-jet the margins or borders are not required either, but having them insures things go well even with curled pages and all, the head comming off the edge of the page. Borderless on ink-jet is not always perfect, even when the machine will allow it. – Psycogeek – 2014-12-29T10:23:24.023

@fixer1234 added defect info. – Sparr – 2014-12-29T14:57:13.590

@kreemoweet the official drivers on windows, mac, and linux say there is a mininum, and when I try to print larger than the margins I get some white area on the edges cutting off my print. This also happens with the standard postscript driver on linux (CUPS) and windows. – Sparr – 2014-12-29T14:58:37.130

Just a guess, but one reason for a margin is to ensure that any toner goes only on the paper (applies to inkjets, too). Toner or ink that is off the paper will crap up the inside of the printer. Don't know if that is the reason here. Even commercial printers achieve edge to edge printing (called "full bleed"), by printing on oversized paper and then trimming it. Photo printers that make borderless prints usually rely on a precision mechanism and paper edge sensors. – fixer1234 – 2014-12-29T19:03:43.397

Answers

Most printers do not print full bleed (i.e. to the edge of the paper). According to this link, the Laserjet 3800 does not. The data sheet confirms that the 3800 uses the normal 5 mm margins.

For printers that do offer full bleed, the printer default is nearly always to use standard margins anyway. To get full bleed you usually need to change a setting on the printer.

hdhondt

Posted 2014-12-28T20:33:37.883

Reputation: 3 244

Right. The point of the question is that it isn't supposed to do that but it did while there was a defect. That means the hardware is there to print full bleed, but that capability has been purposely suppressed. Why not let users use it if the printer is capable of it? – fixer1234 – 2014-12-31T00:23:03.047

Full bleed means that toner will spill over the edge of the paper, and the printer's internal housekeeping will need to clean that up. That costs extra money in design & manufacturing. – hdhondt – 2015-01-01T01:26:21.900

@hdhondt the printer ran dozens or hundreds of full-bleed-in-one-color pages while experiencing and then diagnosing the problem, and it still works. I'm perfectly willing to clean the internals myself, manually, after such an operation, if I could figure out how to make it happen intentionally. – Sparr – 2015-01-01T12:52:30.563

Why can't the printer do that intentionally in normal circumstances?

The short answer appears to be: it can. But a long time has gone by since you posted; did you ever figure out an override? That's the question I have.

I was just trying to update some business cards originally composed sometime in the 1990s with a DOS version of WordPerfect. The margins were originally set for 0.1 inches, and those settings still work (on an HP 2605 I'm pretty sure didn't even exist then)! But if I try and make changes, the minimum margin is now forced to 0.167 inches.

I remember being annoyed at the minimum that appeared when Windows applications replaced DOS applications using the same printer. As you discovered, it obviously has nothing to do with the hardware. The way this appears to work is that the driver gives the application a minimum number which for some inexplicable reason is strictly enforced during document creation but which is not checked at print time.

A possible solution would appear to be to find a printer that allows borderless printing (or very nearly that) and install a driver for it, format the document for that printer, and switch to the desired printer for actual printing. Or buy that printer :) .

I'm willing to try this if anyone knows of such a printer, but I'm not up to installing dozens of drivers for printers I don't have just to find one that might be usable, and I can't find a list.

InquiringMind

Posted 2014-12-28T20:33:37.883

Reputation: 21

Welcome to Super User. This all sounds pretty speculative. The site's purpose is to build a knowledgebase, and answers are intended to be definitive. If you aren't sure about something, you should research it or test it before posting it as an answer. Speculative solutions can be posted as a comment and moved to an answer if it turns out to be one. – fixer1234 – 2015-10-13T03:48:21.510