Mendel90 VS dotSCAD

Old issue, but annoying nonetheless. Less of a problem when outputting STL files (for printing) which only support polylines and not arcs/circles. Funnily enough, 3D printers nowadays support arcs natively in G-code, so some slicers support detecting rounded polylines and converting them back into circles or arcs.

Found a script[0] that does this for DXFs in a github issue[1].

[0]: https://github.com/nophead/Mendel90/blob/master/dxf.py

But the darwin was a pretty terrible design, why not Mendel90 or something?

For anyone interested in details, I suggest taking a look at the github repository https://github.com/nophead/Mendel90/

I think one of the most amazing expressions I've seen of this so far is Nophead's Mendel90 - a 3D printer design that's fully parametric, to the point where you can not only select basically any size you want and get all the manufacturing files out, but even change everything from the whole style of the printer to what bolts you want to use, and then generate exploded diagrams of each sub-component.

If you're looking for examples of high quality openscad code, dotSCAD is pretty cool. nophead (old school reprap person and one of the openscad developers) has a parts library that I think is high quality.

Justin Lin passed away due to illness in 2022 at the age of 48.[0]

On December 22, 2022 OpenSCAD posted:

> Today's advent calendar door is a sad one. We'd like to commemorate Justin Lin, who passed away a while ago. In the OpenSCAD community he is best known for his #dotSCAD library. His designs always brought joy and amazement. Thank you, we will miss you.[1,2]

On October 11, 2022 dotSCAD v3.3 released — it was the last commit by JustinSDK on GitHub.[3]

[0] https://www.ithome.com.tw/caterpillar

[1] https://twitter.com/openscad/status/1605758512746881025

[2] https://fosstodon.org/@OpenSCAD/109555037335637650

[3] https://github.com/JustinSDK/dotSCAD/releases/tag/v3.3

https://github.com/JustinSDK/dotSCAD - as far as I can tell this is widely used

I synced your repo: https://github.com/JustinSDK/dotSCAD

// require https://github.com/JustinSDK/dotSCAD use use use n = 5; radius = 10; thickness = 1; geom = geom_icosahedron(radius); points = geom[0]; faces = geom[1]; for(f = faces) { triangle = [for(i = f) points[i]]; // subdivide the triangle triangles = tri_subdivide(triangle, n); points1 = [ for(t = triangles, p = t) let(unit_vector = p / norm(p)) unit_vector * radius ]; points2 = [ for(t = triangles, p = t) let(unit_vector = p / norm(p)) unit_vector * (radius - thickness) ]; ff = [for(i = [0:3:len(points1) - 3]) [i, i + 1, i + 2]]; color(rands(0, 1, 3)) sf_solidifyT(points1, points2, ff); }

If you are into OpenSCAD, grab this chap's work - https://github.com/JustinSDK/dotSCAD/tree/master/src and use his modules, they are rather good.

// use // a shape function from https://github.com/JustinSDK/dotSCAD // sq_outer = shape_square(size = 50, corner_r = 5); sq_outer = [[20, -25], [21.9471, -24.6053], [23.5868, -23.4835], [24.6602, -21.8118], [25, -20], [25, 20], [24.6053, 21.9471], [23.4835, 23.5868], [21.8118, 24.6602], [20, 25], [-20, 25], [-21.8118, 24.6602], [-23.4835, 23.5868], [-24.6053, 21.9471], [-25, 20], [-25, -20], [-24.6602, -21.8118], [-23.5868, -23.4835], [-21.9471, -24.6053], [-20, -25]]; // sq_inner = shape_square(size = 30, corner_r = 3); sq_inner = [[12, -15], [13.8551, -14.3577], [14.9158, -12.7057], [15, -12], [15, 12], [14.3577, 13.8551], [12.7057, 14.9158], [12, 15], [-12, 15], [-12.7057, 14.9158], [-14.3577, 13.8551], [-15, 12], [-15, -12], [-14.9158, -12.7057], [-13.8551, -14.3577], [-12, -15]]; polygon( points = concat(sq_outer, sq_inner), paths = [ [each [0:len(sq_outer) - 1]], [each [len(sq_outer):len(sq_outer)+ len(sq_inner) - 1]] ] );

path_extrude from https://github.com/JustinSDK/dotSCAD library. This kinda works.