39 lines
1.1 KiB
OpenSCAD
39 lines
1.1 KiB
OpenSCAD
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D=300; // start diameter
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N=1; // number of spirals
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FN=100;
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$fn=FN;
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include <../libraries/path_extrude.scad>;
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/**
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* Distinction from spiral_3: use of for loop and union to join rotations. Somehow
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* got it into my head that this was faster? It does adjust the facet size to the
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* diameter.
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**/
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module spiral (count = 40, start_d = 48, spacing = 2.075) {
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facet_size = 30;
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bottom = 1.2;
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top = .4;
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top_offset = (bottom - top);
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h = 2.2;
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od = start_d + (spacing * 2 * count);
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echo("SPIRAL LENGTH", PI * count * (od + start_d + 1) / 2);
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echo("OUTER D", od);
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facetProfile = [[0, 0], [top_offset, -h], [bottom, -h], [bottom, 0]];
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union () {
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for (s = [0 : count - 1]) {
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d = start_d + (s * spacing * 2);
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c = PI * pow(d / 2, 2);
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$fn = ceil( c / facet_size );
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angle_i = 360 / $fn;
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increment = spacing / $fn;
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spiralPath = [ for(t = [0 : $fn + 1]) [((d / 2) + (t * increment)) * cos(t * angle_i), ((d / 2) + (t * increment)) * sin(t * angle_i), 0] ];
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path_extrude(exShape=facetProfile, exPath=spiralPath);
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}
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}
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}
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spiral(N, D);
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