Ultimate Runout Sensor

If you print FDM, you have run out of filament during a job and it is infuriating. Most runout sensors use a friction microswitch with creates drag and sometimes triggers false runouts. Optical sensors are great until you use a transparent or semitransparent filament...then they fail.

So I designed this... over engineered, yes... but it works flawlessly with zero drag.

Due to the tolerances, I would highly recommend resin printing the case and arm. The bracket can easily be FDM printed.

Bearings:
https://www.amazon.com/dp/B08H2B8TT1?ref_=ppx_hzsearch_conn_dt_b_fed_asin_title_1

Source sensor or any cheap sensor that looks similar. It likely contains the same board:
https://www.amazon.com/Creativity-Printer-Filament-Detection-Detecting/dp/B087325BPG/ref=sr_1_3?crid=2QLDGN9VW8C3X&dib=eyJ2IjoiMSJ9.j3sUmSDQxVsusKXVMwaubWeu6OtQkjKUomc8nCo4bi0_mEtqQMWSPer6Hd3GHcMr3GYp5wyIlDNpmHBHqgcSb1uzhFDa7phrlKi34FmTR4wo2AxcwgANvK6zOBW1RGPSoszkhUMqK8cSLeOCdew1MhcJ1oHMKzbcmajnrCyYs_LSs61qKWg7YZLjKOmJNI2