Man-in-the-Middle PCB Unlocks HP Ink Cartridges (opens in new tab)

HP cartridges attach the thermal print head to the ink tanks. The calibration is likely for controlling those heads. Each one has tiny heating elements that need to vaporize the ink at a precise temperature. Thermal heads eventually need to be replaced.

Compare to Epson printers that use piezoelectric heads. Those mechanically push droplets through. This is more complicated, but makes smaller dots.

At least on my HP printer, there is a process (I think called alignment?) to self-calibrate new cartridges. I am not sure if that is different from the type of calibration you’re talking about (maybe about colors). However, I’ve personally not found differences between using the printer’s own calibration processes and not doing anything. Nor have I found significant differences between first and third party cartridges. Some third party cartridges will print a little bit ‘fuzzier’, or maybe ‘thicker’ is the right way to put it. But not in a way that makes the printing worse, as much as different.

The interposer could block or spoof just the “ink level” data and let the rest pass through.

Pro tip: many businesses are getting rid of their old laserjet printers.

You can pick up one for cheap or free and there are cheap 3rd party laser cartridges that will last a normal households for years.

As an infrequent printer (a few pages every few months), their ink subscription plan (Instant Ink) is awesome for us. For $1/mo you get 10 pages (color included), and overages are 10 cents/pg.

So basically for $12 a year we can have a home printer but never have to worry about cartridges. They just show up in the mail when we need more, and the used ones can be recycled in the included mailer.

Yeah. Either buy their printers and throw them away when the sample ink runs out (because, while you are correct about HP, you are also a terrible person that hates the earth), or just buy from a different brand.

Having said that, we have an old Samsung laser printer, and the Samsung printer business was bought by HP since we got it. Recently, HP started shorting me on toner in the replacement cartridges (they cartridges go streaky with 25%+ “toner remaining”).

Switching to third-party ones that bypasses HP’s authenticity checks was clearly the right move (they’re higher quality, cheaper, and also, screw hp).

Plotters are really only good at drawing vector plots. Graphs, schematics, line drawing kind of stuff. Plotters are very bad at text.

I'd wager that something like 99% of all pages printed annually are exclusively text and/or raster images (photos).

Very close to nobody has a use for a plotter, and traditional printers can do 99.99% of the jobs a plotter can do. There's simply not one reason for the average consumer to use a plotter. If you're in an industry where you do actually need a plotter, they're available at industrial prices.

Plotters are cool, but they were only useful when the only other option was monochrome dot matrix. Even then they were extremely limited and not widely used.

If plotters can't compete with dot matrix there's no point even discussing whether they can compete with inkjet or laser.

Plotters don't really represent most people's use-cases. They're slow, and hard to use because they work with vector representations, so you can't really just print an arbitrary document and get acceptable results.

Edge case of an edge case I imagine.

I can’t remember the last time I saw a plotter in a store either.

That said, it wouldn’t be hard to convert any standard 3D printer into a plotter. Keep Z at 0, rubber band a marker to the side of the print head is probably all it would take.

It would take a long time to render photographs that way... If I'm printing something I either need 30 of something to hand out or I want a very high quality decoration on gloss paper.

Because you didn't create it yet.