Spring Loaded Contact Plate

thingiverse

This design is a Z homing plate for CNC that essentially is an upside down BLTouch. Any object that applies a downward force greater than ink pen springs will be able to force the leads to contact each other and trigger the endstop. I used 5 - M3 screws, 2 of which also use 2 nuts in a jamnut fashion to securely contact each eye terminal on each lead. You'll need to play around with whatever you have on hand to assemble the model, but the concept is pretty straight forward. Hardware - 5 - M3 screws of about 10-15mm in length 3 - ink pen springs I've found not all springs are of the same dimension, so you'll need to measure the diameter and length of your springs, and input those numbers into the .scad file, then uncomment each module to render the 3 models and generate new STL files if your spring dimensions aren't the same as mine. OpenSCAD is a lot easier to use than you think. If you're competent enough to modify Marlin Firmware, you can also modify a scad file. https://www.youtube.com/watch?v=TDo0P6mRTpk