Ender 3 filament runout sensor
thingiverse
You will need a microswitch and some wires to plug it into the GPIO port of your Raspberry with Octoprint and the Filament runout reloaded plugin. This is the switch I used https://grobotronics.com/microswitch-mini-spdt-on-on-with-roller.html You will need support to print it. The lid slips in and holds nicely with friction, so no screws needed. Added bonus: This works also nicely as a filament guide. Update: I revised the case so that it stands off the frame and more in line with the extruder.
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