trailerhubcap.scad

   1 maindia = 29.7;
   2 poleholeh = 5.0;
   3 polecovth = 0.4;
   4 poleholerad = 6;
   5
   6 mainoverlap = 1.5;
   7
   8 hookbasew = 3.5;
   9 hookfullw = 6;
  10 hookheight = 4.5;
  11 hookwidth = 5;
  12 hookbevelw = 0.75;
  13 hookbevelh = 1.5;
  14
  15 fingernaildepth = 5;
  16 fingernailheight = 2.5;
  17 fingernailwidth = 6;
  18
  19 bigrad = maindia/2 + mainoverlap;
  20 mainth = poleholeh + polecovth;
  21 hooklessdepth = hookfullw - hookbasew;
  22
  23 module base() {
  24   rotate_extrude(convexity=10)
  25     mirror([1,0,0])
  26     polygon(points=[[-bigrad, 0],
  27                     [-bigrad + mainth, -mainth],
  28                     [0, -mainth],
  29                     [0, -poleholeh],
  30                     [-poleholerad, -poleholeh],
  31                     [-poleholerad, 0]]);
  32 }
  33
  34 module fingernails() {
  35   for (ang=[60,180,300])
  36     rotate([0,0,ang])
  37       translate([bigrad - fingernaildepth,
  38                  -fingernailwidth/2,
  39                  -fingernailheight])
  40       cube([fingernaildepth + 1, fingernailwidth, fingernailheight + 1]);
  41 }
  42
  43 module hookrim() {
  44   rotate_extrude(convexity=10)
  45     mirror([1,0,0])
  46     translate([-maindia/2, 0, 0])
  47     polygon(points=[[hooklessdepth, 0],
  48                     [hookfullw, 0],
  49                     [hookfullw*0.33, hookheight],
  50                     [hookbevelw, hookheight],
  51                     [0, hookheight-hookbevelh],
  52                     [0, hooklessdepth]]);
  53 }
  54
  55 module hooktriangles() {
  56   for (ang=[0,120,240]) {
  57     rotate([0,0,ang]) {
  58       translate([0,0,-1]) {
  59         linear_extrude(height=hookheight+2) {
  60           polygon(points=[[0, 0],
  61                           [maindia/2 + 1, -hookwidth],
  62                           [maindia/2 + 1, +hookwidth]]);
  63         }
  64       }
  65     }
  66   }
  67 }
  68
  69 difference(){
  70   base();
  71   fingernails();
  72 }
  73 intersection(){
  74   hookrim();
  75   hooktriangles();
  76 }