brompton-computer-guard.scad

   1 // -*- C -*-
   2
   3 arch_height = 24;
   4 arch_width = 75;
   5 end_width = 25;
   6
   7 arch_thick = 5;
   8
   9 // computed
  10
  11 arch_alpha = atan(arch_height / (arch_width/2));
  12 arch_beta = 2*arch_alpha;
  13 echo(arch_alpha,arch_beta);
  14 arch_in_rad = arch_width/2 / sin(arch_beta);
  15 arch_to_chord = arch_in_rad * cos(arch_beta);
  16
  17 end_thick = arch_thick;
  18
  19 //arch_to_chord = (arch_width/2)*(arch_width/2)/arch_height;
  20 //arch_in_rad = arch_to_chord + arch_height;
  21 //arch_in_rad2 = sqrt(arch_to_chord*arch_to_chord +
  22 //                  (arch_width/2)*(arch_width/2));
  23
  24 //echo(arch_in_rad, arch_in_rad2);
  25
  26 module ArchProfile(){
  27   intersection(){
  28     translate([-200,0])
  29       square([400,200]);
  30     union(){
  31       translate([0,-arch_to_chord]){
  32         difference(){
  33           circle(arch_in_rad + arch_thick, $fa=0.1);
  34           circle(arch_in_rad, $fa=0.1);
  35         }
  36       }
  37       for (m=[0,1])
  38         mirror([m,0])
  39           translate([arch_width/2,0])
  40           square([end_width, end_thick]);
  41     }
  42   }
  43   %square([arch_width/2,arch_height]);
  44 }
  45
  46 ArchProfile();