brompton-computer-guard.scad

   1 // -*- C -*-
   2
   3 cover_ysz = 45;
   4 cover_len = 70;
   5
   6 tube_dia = 18;
   7
   8 attach_cx = -15;
   9 attach_cdy = -5;
  10 attach_w = 25;
  11
  12 attach_inrad = 25; ///
  13 attach_hole_dist = 5; ///
  14 attach_hole_dia = 4 + 0.5; ///
  15 attach_ang = 45;
  16
  17 attach_dz = 2;
  18
  19 comp_dx = 22;
  20 comp_xsz = 45;
  21 comp_zsz = 28;
  22
  23 leftend_zsz = 10;
  24 leftend_dz = comp_zsz * 0.6;
  25
  26 min_thick = 4;
  27
  28 rightend_thick = 10;
  29 bolthead_space = 4;
  30
  31 // calculated
  32
  33 cover_lcircle_r = cover_ysz / (1 + 1/sqrt(2));
  34
  35 base_len = cover_len - cover_lcircle_r;
  36
  37 attach_end_r = attach_w/2;
  38
  39 attach_straight_len =
  40   attach_inrad + tube_dia + attach_hole_dist + attach_hole_dia/2
  41   - attach_end_r + attach_hole_dist;
  42
  43 attach_down = tube_dia/2 + attach_dz;
  44
  45 attach_xmax = attach_cx +
  46   cos(attach_ang) * attach_straight_len + attach_end_r;
  47
  48 module RearSideTemplate(){
  49   polygon([[0.1,0],
  50            [-base_len,0],
  51            [-base_len,-cover_ysz],
  52            [0.1,      -cover_ysz]]);
  53   translate([-base_len, -cover_ysz + cover_lcircle_r])
  54     circle(r=cover_lcircle_r);
  55 }
  56
  57 module AttachTemplate(){
  58   hull(){
  59     polygon([[0,   0],
  60              [-0.1, 0],
  61              [-0.1, -cover_ysz],
  62              [0,    -cover_ysz]]);
  63     translate([attach_cx, -attach_cdy]) rotate([0,0,-attach_ang]) {
  64       polygon([[-attach_cx,          attach_w/2],
  65                [0,                   -attach_w/2],
  66                [attach_straight_len, -attach_w/2],
  67                [attach_straight_len, attach_w/2]]);
  68       translate([attach_straight_len, 0])
  69         circle(r=attach_end_r);
  70     }
  71   }
  72 }
  73
  74 module AttachElevation(anddown){
  75   hull(){
  76     translate([-cover_len - 0.5, leftend_dz - leftend_zsz/2])
  77       square([1, leftend_zsz]);
  78     translate([-comp_dx - comp_xsz/2, -0.1])
  79       square([comp_xsz, comp_zsz + min_thick]);
  80     translate([attach_xmax, 0])
  81       square([1, rightend_thick + bolthead_space]);
  82   }
  83   if (anddown)
  84     translate([-comp_dx, -attach_down-5])
  85       square([comp_dx + attach_xmax+2, attach_down+6]);
  86 }
  87
  88 module AttachElevationSelector(anddown) {
  89   translate([0,100,0]) rotate([90,0,0]) linear_extrude(height=200)
  90     AttachElevation(anddown);
  91 }
  92
  93 module BodyPositive(){
  94   intersection(){
  95     linear_extrude(height=60) RearSideTemplate();
  96     AttachElevationSelector(false);
  97   }
  98   intersection(){
  99     translate([0,0,-attach_down]) linear_extrude(height=100) AttachTemplate();
 100     AttachElevationSelector(true);
 101   }
 102 }
 103
 104 module Cutouts(){
 105   Tube();
 106   Bolts();
 107 }
 108
 109 module Body(){
 110   difference(){
 111     intersection(){
 112       BodyPositive();
 113       translate([-100,-200,-100]) cube([200,200,200]);
 114     }
 115     Cutouts();
 116   }
 117 }
 118
 119 module Tube(){
 120   translate([attach_cx, -attach_cdy, -tube_dia/2 - 0.1 - attach_dz]) {
 121     rotate_extrude(convexity=10) {
 122       translate([attach_inrad + tube_dia/2, 0])
 123         circle(r=tube_dia/2);
 124     }
 125   }
 126 }
 127
 128 module Bolt(){
 129   translate([0,0,-50]) linear_extrude(height=80) {
 130     circle(r=attach_hole_dia/2, $fn=20);
 131   }
 132   translate([0,0,rightend_thick]) linear_extrude(height=80) {
 133     circle(r=attach_hole_dia/2 * 2, $fn=20);
 134   }
 135 }
 136
 137 module Bolts(){
 138   translate([attach_cx, -attach_cdy]) rotate([0,0,-attach_ang]) {
 139     translate([attach_inrad - attach_hole_dist - attach_hole_dia/2, 0])
 140       Bolt();
 141     translate([attach_inrad + tube_dia
 142                +attach_hole_dist + attach_hole_dia/2, 0])
 143       Bolt();
 144   }
 145 }
 146
 147 module Demo(){
 148   Cutouts();
 149   %BodyPositive();
 150 }
 151
 152 //Demo();
 153 Body();