Tronxy X5S Z-axis hall effect sensor endstop mount (or other 2020 v-slot profile)

thingiverse

This is an experimental project designed to test if a super-cheap hall effect (magnetic) z-axis endstop solution can be created for the Tronxy X5S and similar printers at a very low cost. The sensor used in this experiment was a cheap module featuring a multi-turn potentiometer to adjust sensitivity and a comparator to send a sharp on/off signal when triggered. These sensors are sold as the KY-024 Linear Magnetic Hall Sensor in various places, with prices starting from 45 cents on Aliexpress. A pair of these modules was purchased from this listing: https://www.aliexpress.com/item/Free-shipping-1pcs-lot-KY-024-Linear-Magnetic-Hall-Switches-Speed-Counting-Sensor-Module-for-Arduino/32663114987.html. The sensor is said to work with both 3.3v and 5v systems, which was an important consideration since I plan to switch to a 32-bit controller with 3.3v logic in the future. I have verified that this solution works with my RAMPS setup. Note that the sensor's wiring (GND V+ Signal) is different from the standard RAMPS endstop header (Signal Gnd V+), so you will need to use a 3-wire cable with some pins swapped on one end. The "AO" pin provides a variable voltage signal and is not used in this application. If you are using the original Tronxy board or another controller with 2-pin endstop headers, you'll have to identify which pin is ground and which is signal, and then find 5v elsewhere on the board (like the display connector) to solder a wire. In either case, you will have to recompile Marlin because this hall sensor (and optical endstops) are NON-inverted. So you need #define Z_MIN_ENDSTOP_INVERTING false I have included arms that attach to the top or bottom of the Z gantry - either with an M3 screw and a magnet stuck to its head or just a plastic arm to glue a magnet to. I am also adding some lowering blocks with integrated arms for magnet mounting to my set of lowering blocks, available here: https://www.thingiverse.com/thing:3174678 I'm not an expert in this area, but I have concerns about using a hall sensor sideways as a method for an endstop - hopefully it proves to be reliable. You will likely find that the sensor is much more sensitive to one pole of the magnet than the other. For this dirt-cheap sensor and the X5S, I haven't yet found a better way to mount this exact sensor or any others in a way that allows you to use the original Z endstop screw without interfering with the Y axis. I'll keep thinking about it.