I made an attachment for my Ender 3 3D printer that allowed me to turn it into a pen plotter and draw with ink (and other) pens. I've played around with different code to create images (photo->gcode) and made a new youtube channel for the drawings and a bit of behind the scenes of how they're made: https://www.youtube.com/channel/UCfqDAVieav-UOIEAlDXsovQ