I have a friend who is interested in 3d printing but really can't afford a printer. And I have all these parts left over from so many rounds of upgrades on so many printers so I am going to build my friend a 3d printer and give it to him so he can start making stuff, too. I have found an old design from 2013 of a printable i3 frame: https://www.thingiverse.com/thing:146061 . And this thread is dedicated to the printing of this frame and subsequent building of a prusa i3 printer from spare parts.