Parametric Knob for Hex Bolts

thingiverse

A couple of distinct knobs, engineered to fit standard 1/4", 3/8", and 1/2" bolts precisely. The fit should be quite snug simply printing "as-is," but you might need to apply some heat or superglue if it's either too tight or too loose. ABS with four shells/30% fill is probably sufficient to withstand anything you can do by hand, even on a 1/2" bolt; adjust accordingly. These knobs are designed for SAE bolts, though the files themselves are specified in metric, so you won't need to scale them up before slicing/printing. To fit other bolts or adjust the fit, look to the script below. This object was parametrically designed using Python, FreeCAD, and CadQuery, so the code and yet more documentation is available here: https://github.com/swolebro/caddyshack