Small component to trigger an optical coupler endstop on the spindle for the 3018 pro CNC machine. I attached it to the spindle with a M3 screw with a threaded brass insert I drilled and melted into place.

Use black PLA w/ 100% infill. Using other colors will bleed light and will not trigger the sensor. I tried orange with no success.

Optical Endstops: https://www.amazon.com/REIFENG-Optical-Endstop-Switch-Sensor/dp/B07MFT8NWJ?th=1