I am building a Hypercube using yyh1002's B2D extruder, but I wanted a filament run out sensor so I made this. I have yet to test it, but I'm bored at work and decided to upload it to thingiverse.
I'll find some errors in my design eventually, so you can expect to see updates once I've started using it. The first flaw is I didn't add enough clearance for the PCB. It works fine if you scrape up the PCB of the endstop. The second is that the endstop's indicator light doesn't completely go out when you run filament through, so using an optical endstop as the sensor may not work without some fiddling, however I have yet test this.
I'll do some testing as soon as I finish my 300x300x600 hypercube.
I used these by the way WINGONEER Optical limit switches
I used .1 but .2 is good too
Print with the inlet at the bottom. Or print it how you want. Everyone has their methods.