K8200/3Drag Y-Axis optical end stop

thingiverse

Holder for an optical end stop on the Y-Axis equipped with a CNY70 reflective optical sensor. The mechanical end stop is notorious for shaking and swinging excessively, which not only generates noise but also leads to unpredictable trigger outcomes. What's more, it necessitates the use of a finger on the platform, requiring tight adjustment and leaving it out of sight afterwards. On the other hand, the reflective optical sensor mounted atop the belt for the Y-axis is an effective solution that detects endstop touches with precision without making any noise. To ensure accurate detection, place a white marker (2-3 mm wide) on it in the right position (check the pictures). The sharper the edges of the marker are, the better the repeating accuracy of the sensor will be. Connecting the CNY70 is feasible through various methods; I chose this particular configuration: Use a diode with 240 ohms to +5V and GND for connection. Alternatively, use a transistor where Collector is connected to +5V, emitter connected to S, and 2.4 megohms to GND for optimal functionality. Lastly, remember to deactivate the Y-Axis Pullup in software.