OpenSCAD Hirth Joints

thingiverse

https://github.com/mechadense/scad-lib-hirthjoints Author: Lukas M. Süss aka mechadense License: LGPL-3.0 Description: A minimal function for generation of hirth joints. This is more meant as a library. Deliberately kept minimal. Customizer (TODO needs debugging) is just meant as a quick preview of what can be done. Note that there is no math for sanity checking of supplied parameters. ## Usage tipps: ``` use <Hirth.scad> hirth ( n = 12 , r = 24 , zbase = 8 , slant = 60 , a1up = 10 , a1down = 12 , cuttype = "cylindrical" , dbore = 12 , acone = 0 ) ``` - Always keep down_angle bigger than up_angle or the roofs will hit the valleys. - If you use ist as a cutter then increase r and decrease dbore compared to the counterpart such that the teeth will fit radially. - For printing a hirth interface at the bottom of a FFF-3D-print one can avert the need for support material by cutting off half of the teeth. This still meshes with full teeth but not with cutoff teeth. ## Notes: This is the third and so far most performant attempt. It uses convex hulls to span volumes. I found that the crux for hirth joints is to ***operate in spherical rather than in cylindrical coordinates*** ## History of preceding attempts: Elegant but inefficient & buggy (attempt two): Intersections of approximated halfspaces https://www.thingiverse.com/thing:397553 Earliest (attempt one): Vertices and meshing: https://www.thingiverse.com/thing:387292