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561 lines
17 KiB
OpenSCAD
561 lines
17 KiB
OpenSCAD
//////////////////////////////////////////////////////////////////////
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// LibFile: walls.scad
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// Various wall constructions.
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// To use, add the following lines to the beginning of your file:
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// ```
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// include <BOSL2/std.scad>
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// include <BOSL2/walls.scad>
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// ```
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//////////////////////////////////////////////////////////////////////
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/*
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BSD 2-Clause License
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Copyright (c) 2017-2019, Revar Desmera
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All rights reserved.
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Redistribution and use in source and binary forms, with or without
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modification, are permitted provided that the following conditions are met:
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* Redistributions of source code must retain the above copyright notice, this
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list of conditions and the following disclaimer.
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* Redistributions in binary form must reproduce the above copyright notice,
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this list of conditions and the following disclaimer in the documentation
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and/or other materials provided with the distribution.
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THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
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AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
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IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
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DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE LIABLE
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FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
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DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
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SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER
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CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
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OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
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OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
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*/
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// Section: Walls
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// Module: narrowing_strut()
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//
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// Description:
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// Makes a rectangular strut with the top side narrowing in a triangle.
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// The shape created may be likened to an extruded home plate from baseball.
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// This is useful for constructing parts that minimize the need to support
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// overhangs.
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//
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// Usage:
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// narrowing_strut(w, l, wall, [ang], [orient], [anchor]);
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//
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// Arguments:
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// w = Width (thickness) of the strut.
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// l = Length of the strut.
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// wall = height of rectangular portion of the strut.
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// ang = angle that the trianglar side will converge at.
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// orient = Orientation of the length axis of the shape. Use the `ORIENT_` constants from `constants.scad`. Default: `ORIENT_Y`.
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// anchor = Alignment of the shape. Use the constants from `constants.scad`. Default: `FRONT`.
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//
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// Example:
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// narrowing_strut(w=10, l=100, wall=5, ang=30);
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module narrowing_strut(w=10, l=100, wall=5, ang=30, orient=ORIENT_Y, anchor=FRONT)
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{
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h = wall + w/2/tan(ang);
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size = [w, h, l];
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orient_and_anchor(size, orient, anchor, chain=true) {
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fwd(h/2) {
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linear_extrude(height=l, center=true, slices=2) {
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back(wall/2) square([w, wall], center=true);
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back(wall-0.001) {
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yscale(1/tan(ang)) {
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difference() {
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zrot(45) square(w/sqrt(2), center=true);
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fwd(w/2) square(w, center=true);
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}
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}
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}
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}
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}
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children();
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}
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}
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// Module: thinning_wall()
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//
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// Description:
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// Makes a rectangular wall which thins to a smaller width in the center,
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// with angled supports to prevent critical overhangs.
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//
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// Usage:
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// thinning_wall(h, l, thick, [ang], [strut], [wall], [orient], [anchor]);
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//
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// Arguments:
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// h = height of wall.
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// l = length of wall. If given as a vector of two numbers, specifies bottom and top lengths, respectively.
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// thick = thickness of wall.
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// ang = maximum overhang angle of diagonal brace.
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// strut = the width of the diagonal brace.
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// wall = the thickness of the thinned portion of the wall.
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// orient = Orientation of the length axis of the wall. Use the `ORIENT_` constants from `constants.scad`. Default: `ORIENT_X`.
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// anchor = Alignment of the shape. Use the constants from `constants.scad`. Default: `CENTER`.
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//
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// Example: Typical Shape
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// thinning_wall(h=50, l=80, thick=4);
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// Example: Trapezoidal
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// thinning_wall(h=50, l=[80,50], thick=4);
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module thinning_wall(h=50, l=100, thick=5, ang=30, strut=5, wall=2, orient=ORIENT_Z, anchor=CENTER)
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{
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l1 = (l[0] == undef)? l : l[0];
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l2 = (l[1] == undef)? l : l[1];
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trap_ang = atan2((l2-l1)/2, h);
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corr1 = 1 + sin(trap_ang);
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corr2 = 1 - sin(trap_ang);
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z1 = h/2;
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z2 = max(0.1, z1 - strut);
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z3 = max(0.05, z2 - (thick-wall)/2*sin(90-ang)/sin(ang));
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x1 = l2/2;
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x2 = max(0.1, x1 - strut*corr1);
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x3 = max(0.05, x2 - (thick-wall)/2*sin(90-ang)/sin(ang)*corr1);
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x4 = l1/2;
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x5 = max(0.1, x4 - strut*corr2);
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x6 = max(0.05, x5 - (thick-wall)/2*sin(90-ang)/sin(ang)*corr2);
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y1 = thick/2;
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y2 = y1 - min(z2-z3, x2-x3) * sin(ang);
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size = [l1, thick, h];
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orient_and_anchor(size, orient, anchor, size2=[l2,thick], chain=true) {
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polyhedron(
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points=[
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[-x4, -y1, -z1],
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[ x4, -y1, -z1],
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[ x1, -y1, z1],
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[-x1, -y1, z1],
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[-x5, -y1, -z2],
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[ x5, -y1, -z2],
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[ x2, -y1, z2],
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[-x2, -y1, z2],
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[-x6, -y2, -z3],
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[ x6, -y2, -z3],
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[ x3, -y2, z3],
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[-x3, -y2, z3],
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[-x4, y1, -z1],
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[ x4, y1, -z1],
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[ x1, y1, z1],
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[-x1, y1, z1],
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[-x5, y1, -z2],
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[ x5, y1, -z2],
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[ x2, y1, z2],
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[-x2, y1, z2],
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[-x6, y2, -z3],
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[ x6, y2, -z3],
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[ x3, y2, z3],
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[-x3, y2, z3],
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],
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faces=[
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[ 4, 5, 1],
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[ 5, 6, 2],
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[ 6, 7, 3],
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[ 7, 4, 0],
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[ 4, 1, 0],
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[ 5, 2, 1],
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[ 6, 3, 2],
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[ 7, 0, 3],
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[ 8, 9, 5],
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[ 9, 10, 6],
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[10, 11, 7],
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[11, 8, 4],
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[ 8, 5, 4],
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[ 9, 6, 5],
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[10, 7, 6],
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[11, 4, 7],
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[11, 10, 9],
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[20, 21, 22],
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[11, 9, 8],
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[20, 22, 23],
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[16, 17, 21],
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[17, 18, 22],
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[18, 19, 23],
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[19, 16, 20],
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[16, 21, 20],
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[17, 22, 21],
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[18, 23, 22],
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[19, 20, 23],
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[12, 13, 17],
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[13, 14, 18],
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[14, 15, 19],
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[15, 12, 16],
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[12, 17, 16],
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[13, 18, 17],
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[14, 19, 18],
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[15, 16, 19],
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[ 0, 1, 13],
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[ 1, 2, 14],
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[ 2, 3, 15],
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[ 3, 0, 12],
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[ 0, 13, 12],
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[ 1, 14, 13],
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[ 2, 15, 14],
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[ 3, 12, 15],
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],
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convexity=6
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);
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children();
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}
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}
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// Module: braced_thinning_wall()
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//
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// Description:
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// Makes a rectangular wall with cross-bracing, which thins to a smaller width in the center,
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// with angled supports to prevent critical overhangs.
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//
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// Usage:
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// braced_thinning_wall(h, l, thick, [ang], [strut], [wall], [orient], [anchor]);
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//
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// Arguments:
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// h = height of wall.
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// l = length of wall.
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// thick = thickness of wall.
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// ang = maximum overhang angle of diagonal brace.
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// strut = the width of the diagonal brace.
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// wall = the thickness of the thinned portion of the wall.
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// orient = Orientation of the length axis of the wall. Use the `ORIENT_` constants from `constants.scad`. Default: `ORIENT_Y`.
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// anchor = Alignment of the shape. Use the constants from `constants.scad`. Default: `CENTER`.
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//
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// Example: Typical Shape
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// braced_thinning_wall(h=50, l=100, thick=5);
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module braced_thinning_wall(h=50, l=100, thick=5, ang=30, strut=5, wall=2, orient=ORIENT_Y, anchor=CENTER)
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{
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dang = atan((h-2*strut)/(l-2*strut));
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dlen = (h-2*strut)/sin(dang);
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size = [l, thick, h];
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orient_and_anchor(size, orient, anchor, orig_orient=ORIENT_Y, chain=true) {
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union() {
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xrot_copies([0, 180]) {
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down(h/2) narrowing_strut(w=thick, l=l, wall=strut, ang=ang);
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fwd(l/2) xrot(-90) narrowing_strut(w=thick, l=h-0.1, wall=strut, ang=ang);
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intersection() {
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cube(size=[thick, l, h], center=true);
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xrot_copies([-dang,dang]) {
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zspread(strut/2) {
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scale([1,1,1.5]) yrot(45) {
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cube(size=[thick/sqrt(2), dlen, thick/sqrt(2)], center=true);
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}
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}
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cube(size=[thick, dlen, strut/2], center=true);
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}
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}
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}
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cube(size=[wall, l-0.1, h-0.1], center=true);
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}
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children();
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}
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}
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// Module: thinning_triangle()
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//
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// Description:
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// Makes a triangular wall with thick edges, which thins to a smaller width in
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// the center, with angled supports to prevent critical overhangs.
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//
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// Usage:
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// thinning_triangle(h, l, thick, [ang], [strut], [wall], [diagonly], [orient], [anchor|center]);
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//
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// Arguments:
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// h = height of wall.
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// l = length of wall.
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// thick = thickness of wall.
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// ang = maximum overhang angle of diagonal brace.
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// strut = the width of the diagonal brace.
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// wall = the thickness of the thinned portion of the wall.
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// diagonly = boolean, which denotes only the diagonal side (hypotenuse) should be thick.
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// orient = Orientation of the length axis of the shape. Use the `ORIENT_` constants from `constants.scad`. Default: `ORIENT_Y`.
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// anchor = Alignment of the shape. Use the constants from `constants.scad`. Default: `CENTER`.
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// center = If true, centers shape. If false, overrides `anchor` with `UP+BACK`.
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//
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// Example: Centered
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// thinning_triangle(h=50, l=80, thick=4, ang=30, strut=5, wall=2, center=true);
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// Example: All Braces
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// thinning_triangle(h=50, l=80, thick=4, ang=30, strut=5, wall=2, center=false);
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// Example: Diagonal Brace Only
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// thinning_triangle(h=50, l=80, thick=4, ang=30, strut=5, wall=2, diagonly=true, center=false);
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module thinning_triangle(h=50, l=100, thick=5, ang=30, strut=5, wall=3, diagonly=false, center=undef, orient=ORIENT_Y, anchor=CENTER)
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{
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dang = atan(h/l);
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dlen = h/sin(dang);
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size = [thick, h, l];
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orient_and_anchor(size, orient, anchor, center=center, noncentered=BOTTOM+FRONT, orig_orient=ORIENT_Y, chain=true) {
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difference() {
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union() {
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if (!diagonly) {
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translate([0, 0, -h/2])
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narrowing_strut(w=thick, l=l, wall=strut, ang=ang);
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translate([0, -l/2, 0])
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xrot(-90) narrowing_strut(w=thick, l=h-0.1, wall=strut, ang=ang);
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}
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intersection() {
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cube(size=[thick, l, h], center=true);
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xrot(-dang) yrot(180) {
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narrowing_strut(w=thick, l=dlen*1.2, wall=strut, ang=ang);
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}
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}
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cube(size=[wall, l-0.1, h-0.1], center=true);
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}
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xrot(-dang) {
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translate([0, 0, h/2]) {
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cube(size=[thick+0.1, l*2, h], center=true);
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}
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}
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}
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children();
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}
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}
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// Module: sparse_strut()
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//
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// Description:
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// Makes an open rectangular strut with X-shaped cross-bracing, designed to reduce
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// the need for support material in 3D printing.
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//
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// Usage:
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// sparse_strut(h, l, thick, [strut], [maxang], [max_bridge], [orient], [anchor])
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//
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// Arguments:
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// h = height of strut wall.
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// l = length of strut wall.
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// thick = thickness of strut wall.
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// maxang = maximum overhang angle of cross-braces.
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// max_bridge = maximum bridging distance between cross-braces.
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// strut = the width of the cross-braces.
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// orient = Orientation of the length axis of the shape. Use the `ORIENT_` constants from `constants.scad`. Default: `ORIENT_Y`.
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// anchor = Alignment of the shape. Use the constants from `constants.scad`. Default: `CENTER`.
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//
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// Example: Typical Shape
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// sparse_strut(h=40, l=100, thick=3);
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// Example: Thinner Strut
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// sparse_strut(h=40, l=100, thick=3, strut=2);
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// Example: Larger maxang
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// sparse_strut(h=40, l=100, thick=3, strut=2, maxang=45);
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// Example: Longer max_bridge
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// sparse_strut(h=40, l=100, thick=3, strut=2, maxang=45, max_bridge=30);
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module sparse_strut(h=50, l=100, thick=4, maxang=30, strut=5, max_bridge=20, orient=ORIENT_Y, anchor=CENTER)
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{
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zoff = h/2 - strut/2;
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yoff = l/2 - strut/2;
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maxhyp = 1.5 * (max_bridge+strut)/2 / sin(maxang);
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maxz = 2 * maxhyp * cos(maxang);
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zreps = ceil(2*zoff/maxz);
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zstep = 2*zoff / zreps;
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hyp = zstep/2 / cos(maxang);
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maxy = min(2 * hyp * sin(maxang), max_bridge+strut);
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yreps = ceil(2*yoff/maxy);
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ystep = 2*yoff / yreps;
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ang = atan(ystep/zstep);
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len = zstep / cos(ang);
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size = [thick, l, h];
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orient_and_anchor(size, orient, anchor, orig_orient=ORIENT_Y, chain=true) {
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yrot(90)
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linear_extrude(height=thick, convexity=4*yreps, center=true) {
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difference() {
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square([h, l], center=true);
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square([h-2*strut, l-2*strut], center=true);
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}
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yspread(ystep, n=yreps) {
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xspread(zstep, n=zreps) {
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skew_xy(planar=true, ya=-ang) square([(h-strut)/zreps, strut], center=true);
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skew_xy(planar=true, ya= ang) square([(h-strut)/zreps, strut], center=true);
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}
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}
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}
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children();
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}
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}
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// Module: sparse_strut3d()
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//
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// Usage:
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// sparse_strut3d(h, w, l, [thick], [maxang], [max_bridge], [strut], [orient], [anchor]);
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//
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// Description:
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// Makes an open rectangular strut with X-shaped cross-bracing, designed to reduce the
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// need for support material in 3D printing.
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//
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// Arguments:
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// h = Z size of strut.
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// w = X size of strut.
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// l = Y size of strut.
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// thick = thickness of strut walls.
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// maxang = maximum overhang angle of cross-braces.
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// max_bridge = maximum bridging distance between cross-braces.
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// strut = the width of the cross-braces.
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// orient = Orientation of the length axis of the shape. Use the `ORIENT_` constants from `constants.scad`. Default: `ORIENT_Y`.
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// anchor = Alignment of the shape. Use the constants from `constants.scad`. Default: `CENTER`.
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//
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// Example: Typical Shape
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// sparse_strut3d(h=30, w=30, l=100);
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// Example: Thinner strut
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// sparse_strut3d(h=30, w=30, l=100, strut=2);
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// Example: Larger maxang
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// sparse_strut3d(h=30, w=30, l=100, strut=2, maxang=50);
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// Example: Smaller max_bridge
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// sparse_strut3d(h=30, w=30, l=100, strut=2, maxang=50, max_bridge=20);
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module sparse_strut3d(h=50, l=100, w=50, thick=3, maxang=40, strut=3, max_bridge=30, orient=ORIENT_Y, anchor=CENTER)
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{
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xoff = w - thick;
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yoff = l - thick;
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zoff = h - thick;
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xreps = ceil(xoff/yoff);
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yreps = ceil(yoff/xoff);
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zreps = ceil(zoff/min(xoff, yoff));
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xstep = xoff / xreps;
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ystep = yoff / yreps;
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zstep = zoff / zreps;
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cross_ang = atan2(xstep, ystep);
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cross_len = hypot(xstep, ystep);
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supp_ang = min(maxang, min(atan2(max_bridge, zstep), atan2(cross_len/2, zstep)));
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supp_reps = floor(cross_len/2/(zstep*sin(supp_ang)));
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supp_step = cross_len/2/supp_reps;
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|
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size = [w, l, h];
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orient_and_anchor(size, orient, anchor, orig_orient=ORIENT_Y, chain=true) {
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intersection() {
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union() {
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ybridge = (l - (yreps+1) * strut) / yreps;
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xspread(xoff) sparse_strut(h=h, l=l, thick=thick, maxang=maxang, strut=strut, max_bridge=ybridge/ceil(ybridge/max_bridge));
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yspread(yoff) zrot(90) sparse_strut(h=h, l=w, thick=thick, maxang=maxang, strut=strut, max_bridge=max_bridge);
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for(zs = [0:zreps-1]) {
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|
for(xs = [0:xreps-1]) {
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|
for(ys = [0:yreps-1]) {
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|
translate([(xs+0.5)*xstep-xoff/2, (ys+0.5)*ystep-yoff/2, (zs+0.5)*zstep-zoff/2]) {
|
|
zflip_copy(offset=-(zstep-strut)/2) {
|
|
xflip_copy() {
|
|
zrot(cross_ang) {
|
|
down(strut/2) {
|
|
cube([strut, cross_len, strut], center=true);
|
|
}
|
|
if (zreps>1) {
|
|
back(cross_len/2) {
|
|
zrot(-cross_ang) {
|
|
down(strut) cube([strut, strut, zstep+strut], anchor=BOTTOM);
|
|
}
|
|
}
|
|
}
|
|
for (soff = [0 : supp_reps-1] ) {
|
|
yflip_copy() {
|
|
back(soff*supp_step) {
|
|
skew_xy(ya=supp_ang) {
|
|
cube([strut, strut, zstep], anchor=BOTTOM);
|
|
}
|
|
}
|
|
}
|
|
}
|
|
}
|
|
}
|
|
}
|
|
}
|
|
}
|
|
}
|
|
}
|
|
}
|
|
cube([w,l,h], center=true);
|
|
}
|
|
children();
|
|
}
|
|
}
|
|
|
|
|
|
// Module: corrugated_wall()
|
|
//
|
|
// Description:
|
|
// Makes a corrugated wall which relieves contraction stress while still
|
|
// providing support strength. Designed with 3D printing in mind.
|
|
//
|
|
// Usage:
|
|
// corrugated_wall(h, l, thick, [strut], [wall], [orient], [anchor]);
|
|
//
|
|
// Arguments:
|
|
// h = height of strut wall.
|
|
// l = length of strut wall.
|
|
// thick = thickness of strut wall.
|
|
// strut = the width of the cross-braces.
|
|
// wall = thickness of corrugations.
|
|
// orient = Orientation of the length axis of the shape. Use the `ORIENT_` constants from `constants.scad`. Default: `ORIENT_Y`.
|
|
// anchor = Alignment of the shape. Use the constants from `constants.scad`. Default: `CENTER`.
|
|
//
|
|
// Example: Typical Shape
|
|
// corrugated_wall(h=50, l=100);
|
|
// Example: Wider Strut
|
|
// corrugated_wall(h=50, l=100, strut=8);
|
|
// Example: Thicker Wall
|
|
// corrugated_wall(h=50, l=100, strut=8, wall=3);
|
|
module corrugated_wall(h=50, l=100, thick=5, strut=5, wall=2, orient=ORIENT_Y, anchor=CENTER)
|
|
{
|
|
amplitude = (thick - wall) / 2;
|
|
period = min(15, thick * 2);
|
|
steps = quantup(segs(thick/2),4);
|
|
step = period/steps;
|
|
il = l - 2*strut + 2*step;
|
|
size = [thick, l, h];
|
|
orient_and_anchor(size, orient, anchor, orig_orient=ORIENT_Y, chain=true) {
|
|
union() {
|
|
linear_extrude(height=h-2*strut+0.1, slices=2, convexity=ceil(2*il/period), center=true) {
|
|
polygon(
|
|
points=concat(
|
|
[for (y=[-il/2:step:il/2]) [amplitude*sin(y/period*360)-wall/2, y] ],
|
|
[for (y=[il/2:-step:-il/2]) [amplitude*sin(y/period*360)+wall/2, y] ]
|
|
)
|
|
);
|
|
}
|
|
difference() {
|
|
cube([thick, l, h], center=true);
|
|
cube([thick+0.5, l-2*strut, h-2*strut], center=true);
|
|
}
|
|
}
|
|
children();
|
|
}
|
|
}
|
|
|
|
|
|
|
|
// vim: noexpandtab tabstop=4 shiftwidth=4 softtabstop=4 nowrap
|