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 * 1.22;
  23
  24 module deck_flange(){
  25   difference(){
  26     cylinder(h = deck_flange_height, r = deck_flange_radius);
  27     for(ii = [-1, 1]){
  28       translate([deck_grid_width * ii, 0, -.1])
  29         cylinder(h = deck_flange_height * 1.1,
  30                  r = deck_flange_screw_radius,
  31                  $fn = 20);}
  32     for(ii = [-1, 1]){
  33       translate([0, deck_grid_width * ii, -.1])
  34         cylinder(h = deck_flange_height * 1.1,
  35                  r = deck_flange_screw_radius,
  36                  $fn = 20);}}}
  37
  38 module deck_flange_reinforcement(){
  39   translate([-deck_flange_radius,
  40              -.5 * deck_flange_height / 2,
  41              deck_flange_height]){
  42     difference (){
  43       cube([deck_flange_radius, deck_flange_height / 2, deck_flange_radius]);
  44       translate([-.1, -.05 * deck_flange_height, 0]){
  45         rotate([0, -45, 0]){
  46           cube([deck_flange_radius * 1.5, // 1.5 is bigger than sqrt(2)
  47                 deck_flange_height * 1.1, // 1.1 is bigger than 1
  48                 deck_flange_radius]);}}}}}
  49
  50 module caster_flange_screws(){
  51   translate([standoff_radius, 0, 0])
  52     cylinder(h = caster_flange_screw_length,
  53              r = caster_flange_screw_radius,
  54              $fn = 20);
  55   translate([-standoff_radius, 0, 0])
  56     cylinder(h = caster_flange_screw_length,
  57              r = caster_flange_screw_radius,
  58              $fn = 20);}
  59
  60 module caster_flange(){
  61   side_radius = caster_flange_width / 2 - standoff_radius;
  62   hull(){
  63     cylinder(h = caster_flange_height, r = standoff_radius);
  64     translate([standoff_radius, 0, 0])
  65       cylinder(h = caster_flange_height, r = side_radius);
  66     translate([-standoff_radius, 0, 0])
  67       cylinder(h = caster_flange_height, r = side_radius);}}
  68
  69 module nut(size, height){
  70     width = size/1.75;
  71     for (r = [-60, 0, 60]) rotate([0,0,r]) cube([width, size, height], true);}
  72
  73 module nuts(){
  74   translate([standoff_radius, 0, nut_height/2])
  75     nut(nut_short_side, nut_height + .1);
  76   translate([-standoff_radius, 0, nut_height/2])
  77     nut(nut_short_side, nut_height + .1);}
  78
  79 module _2_screw (){
  80   //measured with calipers
  81   screw_length = 8;
  82   thread_radius = 2.17 / 2 - 0.1; // subtract 0.1 to make squeeze fit
  83   head_height = 1.8;
  84   head_radius = 4.1 / 2;
  85   cylinder(r = thread_radius, h = screw_height, $fn = 20);
  86   cylinder(r = head_radius, h = head_height, $fn = 20);}
  87
  88 module caster_standoff_deck_side(){
  89   difference(){
  90     cylinder(h = standoff_height - caster_flange_height,
  91              r = standoff_radius,
  92              $fn = 50);
  93     translate([0, 0, standoff_height - caster_flange_screw_length * 1.1 + 0.1])
  94       scale([1, 1, 1.1])
  95         caster_flange_screws();
  96     translate([0, 0, standoff_height - (caster_flange_height + nut_height)])
  97       nuts();
  98     translate([0, 0, standoff_height]){
  99       // make hole to get to screw head depth
 100       cylinder(r = 4.1 / 2, h = 3, center = true, $fn = 20);
 101       translate([0, 0, -0.7])
 102         rotate([180, 0, 0])
 103           _2_screw(r = 0.5, h = 5, $fn = 20);}}
 104   deck_flange();
 105   for(ii = [0:3]){
 106     rotate([0, 0, 45 + 90 * ii])
 107       deck_flange_reinforcement();}}
 108
 109 module caster_standoff_caster_side(){
 110   difference(){
 111     caster_flange();
 112     translate([0, 0, caster_flange_height - 0.7]){
 113       rotate([180, 0, 0]){
 114         _2_screw();}}
 115     // make hole to get to screw head
 116     translate([0, 0, caster_flange_height - 0.8]){
 117       cylinder(r = 4.1 / 2, h = 10, $fn = 20);}
 118     translate([0, 0, -.1]){
 119       caster_flange_screws();}}}
 120
 121 caster_standoff_deck_side();
 122 translate([caster_flange_width / 2 + deck_flange_radius + 1, 0, 0]){
 123   caster_standoff_caster_side();}