There is apparently a printer that can use spent coffee or tea leaves to print. I love this idea but I would not buy a printer when so many are being thrown away. I pull them out of dumpsters with intent to repair them. So the question is, can they be hacked to work with coffee or tea?
Canon actually disclosed how to hack their cartridges as a consequence of a semiconductor shortage due to coronavirus. So this suggests #Canon could be a candidate for this hack. Has anyone tried it? How precisely do we have to match the viscosity of homemade ink to the original ink?
That printer was the only thing I found that demonstrates the use of coffee or tea for printing but it’s not how I would hack a factory ink printer. I would not retrofit the printer to have a hopper. There are recipes out in the wild on making the ink on your stove, which apparently goes into a conventional printer. The recipe I found seemed to say boil it down to thicken it, which I would not have much confidence in. So the problem seems to boil down to finding hackable printers (which IIUC rules out HP), and getting the right viscosity.
It looks like there might be some invidious videos on this but my connection isn’t suitable for it ATM.