Filament runout sensor for a generic endstop

thingiverse

I was attempting to utilize a filament sensor compatible with some spare endstops I had on hand, enabling me to exhaust all of my PLA for the COVID-19 crisis. Upon investigation, various methods that didn't fit my sensor size or malfunctioned due to stuck filament in the endstop hole were tried and evaluated. Valuable insights came from examining these earlier designs: * https://www.thingiverse.com/thing:2665162 * https://www.thingiverse.com/thing:1698397 The approach involves printing two pieces of the provided STL file, securing the endstop with 1.75mm spare filament, and then closing it using three M3 bolts. Attaching a PTFE tube to both sides is optional but can be done. The endstop is connected to the desired sensor pins. In this instance, I'm utilizing Marlin's default pin, which is the fourth one. Please refer to the design photos for further details. My printer features direct extrusion. By simply commenting out FILAMENT_RUNOUT_SENSOR in Configuration.h from Marlin 1.1.9 and adhering to the compiler output recommendations, all requirements were met without needing any additional modifications.