In my last inkjet project I built a piezo inkjet printer from scratch made of cheap electronics, pneumatic and 3D printed parts. I could get it to work, but I had a few problems with the reliability. The drop size was quite large, keeping the ink supply pressure steady was quite difficult and sometimes there formed drops on the nozzle or air got sucked into the printhead what both prevented the printhead from working. There also was a problem with clogging of the nozzle when not in use.

So I looked for a more reliable printing method and choosed Continuous Inkjet Printing.

CIJ printing is (as far as I know) only used in industrial or production applications and therefore super reliable. CIJ printers are working for years 24/7 with only minor maintenance. 

Even though CIJ printers have much more parts than piezo or thermal inkjet printers, all parts have a decent size - no sub millimeter dimension like piezo and thermal inkjet nozzles, so working on them, fixing problems and maybe also manufacturing them will be a lot easier.

Because new CIJ printers are quite expensive and not so easy to order for private persons I bought an used one from ebay. After some cleaning to get it nice and shiny I tried to find out how to get it to work.