trailerhubcap.scad

   1 // Copyright (C)2012 Ian Jackson
   2 // Licenced under the GNU General Public Licence, version 3, or
   3 // (at your option) any later version.  There is NO WARRANTY.
   4
   5 maindia = 29.7;
   6 poleholeh = 5.0;
   7 polecovth = 0.4;
   8 poleholerad = 6;
   9
  10 mainoverlap = 1.5;
  11
  12 hookbasew = 5.0;
  13 hookfullw = 7;
  14 hookheight = 4.5;
  15 hookwidth = 8;
  16 hookbevelw = 0.75;
  17 hookbevelh = 1.5;
  18
  19 fingernaildepth = 5;
  20 fingernailheight = 2.5;
  21 fingernailwidth = 6;
  22
  23 bigrad = maindia/2 + mainoverlap;
  24 mainth = poleholeh + polecovth;
  25 hooklessdepth = hookfullw - hookbasew;
  26
  27 module base() {
  28   rotate_extrude(convexity=10)
  29     mirror([1,0,0])
  30     polygon(points=[[-bigrad, 0],
  31                     [-bigrad + mainth, -mainth],
  32                     [0, -mainth],
  33                     [0, -poleholeh],
  34                     [-poleholerad, -poleholeh],
  35                     [-poleholerad, 0]]);
  36 }
  37
  38 module fingernails() {
  39   for (ang=[60,180,300])
  40     rotate([0,0,ang])
  41       translate([bigrad - fingernaildepth,
  42                  -fingernailwidth/2,
  43                  -fingernailheight])
  44       cube([fingernaildepth + 1, fingernailwidth, fingernailheight + 1]);
  45 }
  46
  47 module hookrim() {
  48   rotate_extrude(convexity=10)
  49     mirror([1,0,0])
  50     translate([-maindia/2, 0, 0])
  51     polygon(points=[[hooklessdepth, 0],
  52                     [hookfullw, 0],
  53                     [hookfullw*0.33, hookheight],
  54                     [hookbevelw, hookheight],
  55                     [0, hookheight-hookbevelh],
  56                     [0, hooklessdepth]]);
  57 }
  58
  59 module hooktriangles() {
  60   for (ang=[0,120,240]) {
  61     rotate([0,0,ang]) {
  62       translate([0,0,-1]) {
  63         linear_extrude(height=hookheight+2) {
  64           polygon(points=[[0, 0],
  65                           [maindia/2 + 1, -hookwidth],
  66                           [maindia/2 + 1, +hookwidth]]);
  67         }
  68       }
  69     }
  70   }
  71 }
  72
  73 difference(){
  74   base();
  75   fingernails();
  76 }
  77 intersection(){
  78   hookrim();
  79   hooktriangles();
  80 }