Tactile switch adjustable Z endstop for Prusa i3

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This part screws to the front of the Prusa i3 box frame as shown. It could easily be modified to fit the aluminum frame unit instead. This component is specifically designed for a #6 screw, but you can use others with some adjustments. Just change the nut and screw diameters at the top of your SCAD file. One of the screw diameters should be slightly smaller than the other to prevent the screw from creeping around and making noise. I've found this system to be more accurate and repeatable than a microswitch, easier to mount and adjust than an optical switch. Hall switches I've tried tend to drift at varying temperatures and over time. Insert the wires through the holes in the switch carrier bit, then solder them to the tactile switch. After that, pull the switch down into its holder. Next, place the screw holder onto the X rails as shown, leaving 5 to 10 mm of space between the X end and the screw holder for adjustment purposes. Screw the switch holder to the front of your machine so that the switch lines up with the screw and will get pressed at the right Z height. You can now tap the screw holder along the X axis until the screw lines up perfectly with the switch. Finally, adjust the Z height as needed.