M3 screw knob (parametric)

thingiverse

Human: I designed this for M3 knurled screws sourced from Amazon. I'm combining these with embedded M3 nuts and multiwave washers to adapt legs and feet from MichaelTV's Iris case onto AGuyFromOhio's Ergodox case. The Customizer app allows you to adjust knob and socket sizes, as well as knurling, or edit the included OpenSCAD file directly to fit your needs. My goal was to create something large enough to be practical yet small enough not to hinder case build progress. Screw head sockets are shallow, ensuring knobs stop about a tenth of a millimeter short of the screw head's bottom lip, preventing rubbing against tent legs. Socket depth is 3mm and knob length is 7.5mm, adding approximately 4.5mm to screw head length. The knob's diameter is 10mm. Three STL files with different socket diameters are included for variable tweaking. I find the 5.75mm socket best fits M3 screws sourced from Amazon, but results may vary based on filament used and screw head size. I also use super glue to secure the knob to the screw head.