challenge-bot.com Git - challenge-bot/blob - caster-standoff.scad

   1 // challenge-bot
   2 // GNU AGPLv3 (or later at your option)
   3 // project available at these locations:
   4 // https://gitorious.org/ozzloy/challenge-bot
   5 // https://github.com/waynegramlich/challenge-bot
   6
   7 standoff_radius = 14.732 / 2; // 0.580 / 2 inches from spec sheet
   8 standoff_height = 55; // eyeballed
   9
  10 nut_short_side = 4.7; // from calipers
  11 nut_height = 1.6; // from calipers
  12
  13 // eyeballed caster flange height, (0.580/5) inches, times 2 to be stronger
  14 caster_flange_height = 5;
  15 caster_flange_width = 20.32;  // 0.800 inches
  16 caster_flange_screw_radius = 2.286 / 2;  // 0.090 inches
  17 caster_flange_screw_length = 8; // eyeballed
  18
  19 deck_grid_width = 25.4; // measured center to center on grid on pegboard
  20 deck_flange_height = 2.9464;
  21 deck_flange_screw_radius = 3.556 / 2;  // For #6 machine screws
  22 deck_flange_radius = (deck_grid_width) / 2 + deck_flange_screw_radius + 3;
  23
  24 module deck_flange(){
  25   difference(){
  26     cylinder(h = deck_flange_height, r = deck_flange_radius, $fn = 50);
  27     for(ii = [-1, 1]){
  28       translate([deck_grid_width / 2 * ii, 0, -.1])
  29         cylinder(h = deck_flange_height * 1.1,
  30                  r = deck_flange_screw_radius,
  31                  $fn = 20);
  32       translate([0, deck_grid_width / 2 * ii, -.1])
  33         cylinder(h = deck_flange_height * 1.1,
  34         r = deck_flange_screw_radius,
  35         $fn = 20);}}}
  36
  37 module deck_flange_reinforcement(){
  38   translate([-deck_flange_radius,
  39              -.5 * deck_flange_height / 2,
  40              deck_flange_height]){
  41     difference (){
  42       cube([deck_flange_radius, deck_flange_height / 2, deck_flange_radius]);
  43       translate([-.1, -.05 * deck_flange_height, 0]){
  44         rotate([0, -45, 0]){
  45           cube([deck_flange_radius * 1.5, // 1.5 is bigger than sqrt(2)
  46                 deck_flange_height * 1.1, // 1.1 is bigger than 1
  47                 deck_flange_radius]);}}}}}
  48
  49 module caster_flange_screws(){
  50   translate([standoff_radius, 0, 0])
  51     cylinder(h = caster_flange_screw_length,
  52              r = caster_flange_screw_radius,
  53              $fn = 20);
  54   translate([-standoff_radius, 0, 0])
  55     cylinder(h = caster_flange_screw_length,
  56              r = caster_flange_screw_radius,
  57              $fn = 20);}
  58
  59 module caster_flange(){
  60   side_radius = caster_flange_width / 2 - standoff_radius;
  61   hull(){
  62     cylinder(h = caster_flange_height, r = standoff_radius, $fn = 100);
  63     translate([standoff_radius, 0, 0])
  64       cylinder(h = caster_flange_height, r = side_radius, $fn = 40);
  65     translate([-standoff_radius, 0, 0])
  66       cylinder(h = caster_flange_height, r = side_radius, $fn = 40);}}
  67
  68 module nut(size, height){
  69     width = size/1.75;
  70     for (r = [-60, 0, 60]) rotate([0,0,r]) cube([width, size, height], true);}
  71
  72 module nuts(){
  73   translate([standoff_radius, 0, nut_height/2])
  74     nut(nut_short_side, nut_height + .1);
  75   translate([-standoff_radius, 0, nut_height/2])
  76     nut(nut_short_side, nut_height + .1);}
  77
  78 module _2_screw (){
  79   //measured with calipers
  80   screw_length = 8;
  81   thread_radius = 2.17 / 2 - 0.1; // subtract 0.1 to make squeeze fit
  82   head_height = 1.8;
  83   head_radius = 4.1 / 2;
  84   cylinder(r = thread_radius, h = screw_length, $fn = 20);
  85   cylinder(r = head_radius, h = head_height, $fn = 20);}
  86
  87 module caster_standoff_deck_side(){
  88   difference(){
  89     cylinder(h = standoff_height - caster_flange_height,
  90              r = standoff_radius,
  91              $fn = 50);
  92     translate([0, 0, standoff_height - caster_flange_screw_length * 1.1 + 0.1])
  93       scale([1, 1, 1.1])
  94         caster_flange_screws();
  95     translate([0, 0, standoff_height - (caster_flange_height + nut_height)])
  96       nuts();
  97     translate([0, 0, standoff_height]){
  98       // make hole to get to screw head depth
  99       cylinder(r = 4.1 / 2, h = 3, center = true, $fn = 20);
 100       translate([0, 0, -0.7])
 101         rotate([180, 0, 0])
 102           _2_screw(r = 0.5, h = 5, $fn = 20);}}
 103   deck_flange();
 104   for(ii = [0:3]){
 105     rotate([0, 0, 45 + 90 * ii])
 106       deck_flange_reinforcement();}}
 107
 108 module caster_standoff_caster_side(){
 109   difference(){
 110     caster_flange();
 111     translate([0, 0, caster_flange_height - 0.7]){
 112       rotate([180, 0, 0]){
 113         _2_screw();}}
 114     // make hole to get to screw head
 115     translate([0, 0, caster_flange_height - 0.8]){
 116       cylinder(r = 4.1 / 2, h = 10, $fn = 20);}
 117     translate([0, 0, -.1]){
 118       caster_flange_screws();}}}
 119
 120 caster_standoff_deck_side();
 121 translate([caster_flange_width / 2 + deck_flange_radius + 1, 0, 0]){
 122   caster_standoff_caster_side();}