zlacker

>>pangor+(OP)
Printers are cheap and widely available, which leaves a DIY printer which is going to be slower, more error-prone and more expensive as a very niche idea. There is a clear benefit to buying or building an open hobby 3D printer, whereas that's harder to argue for a 2D one - while there is a lot of crap around, there's enough workable choices, aftermarket inks/toner works, you likely won't be modifying/tuning a 2D printer the same way you maybe would with a 3D printer, ...

Ink delivery is likely the main challenge (although I've seen some low-res attempts), combined with the speed and precision needed for a good printer - reaching a few hundred DPI requires positioning things quite precisely. Laser printers are interesting, but then you need specialized parts like the drum that I'd expect to be difficult to produce in single quantities.

Open pen plotters are a thing, but again not typically used for normal printing duties.

>>detaro+a2
How about laser engraving tech? Can a laser engraver be tight focused to 300 dpi and power set (or sensed) to just make a mark on white paper? Does the positioning accuracy also need to be improved to get that 300 dpi?

You'd never run out of toner at least.

Edit, answered at least one question: yes engravers do 500 dpi routinely. Here's one: https://www.troteclaser.com/en-us/knowledge/tips-for-laser-u...

>>imglor+Gh
I would not consider an engraver for which you have to call to ask the price as "routine". From what I could find, the cheapest trotec is $16k second hand on ebay (and there is another from their cheap line for $56k second hand). You can hire somebody to handwrite everything you need for that kind of money.

Also, high power lasers are consumables.