Prusa style optical endstop filament sensor

thingiverse

So I wanted a simple filament sensor (well two actually) that would use a simple optical endstop. I'm running a Duet board so this is easy to configure as a run-out sensor. I decided on using this flag approach as I found it more consistent than having the filament pass through the sensor. I was inspired by the Prusa approach. So far it's working well for me.