scad/belt-guide-624-uni.scad

   1 //
   2 // Parametric sleeve-style belt guide for 624, 623 bearings and their ilk.
   3 // mrice
   4
   5 layer_height = 0.3;
   6 hotend_width = 0.5;
   7
   8 wall= hotend_width*3;
   9 clearence= hotend_width/2;
  10
  11 // for 624 bearings:
  12 bearing_d        = 13;
  13 bearing_h        = 5;
  14 bearing_inside_d = 4;
  15 belt_w           = 7;
  16
  17 // for 623 bearings:
  18 //bearing_d = 10;
  19 //bearing_h = 4;
  20 //bearing_inside_d = 3; // hole diameter of the bearing
  21
  22 //guide_outer_d = bearing_d + 12;
  23 flange_h = 3*layer_height;
  24 //flange_d = 21;
  25
  26 hole_for_inner = bearing_d/2+(2*clearence);
  27 r_for_inner = hole_for_inner + (2*hotend_width);
  28 hole_for_outer = r_for_inner+clearence;
  29 r_for_outer = hole_for_outer + (hotend_width*2);
  30
  31 flange_d = 2*r_for_outer + (6*hotend_width);
  32
  33 module belt_guide_base(a) {
  34  if(a) {
  35     cylinder(r=r_for_outer, h=belt_w+flange_h, $fn=50);
  36  }
  37  else {
  38     cylinder(r=r_for_inner, h=belt_w+flange_h, $fn=50);
  39  }
  40  // outer flange
  41  cylinder(r=flange_d/2, h=flange_h, $fn=50);
  42 }
  43
  44 module belt_guide_holes(a){
  45  // hole for the bearing:
  46  if(a) {
  47      #translate([0,0,flange_h+(1-a)*(belt_w-bearing_h-layer_height)]) cylinder(r=hole_for_outer, h=bearing_h+10, $fn=50);
  48  }
  49  else {
  50      #translate([0,0,flange_h+(1-a)*(belt_w-bearing_h-layer_height)]) cylinder(r=hole_for_inner, h=bearing_h+10, $fn=50);
  51  }
  52  // hole for the rod through:
  53  translate([0,0,-1]) cylinder(r=bearing_d/2-wall, h=10, $fn=50);
  54 }
  55
  56 // Final part
  57 module belt_guide(){
  58  difference(){
  59   belt_guide_base(0);
  60   belt_guide_holes(0);
  61  }
  62 }
  63
  64 module belt_guide_sleeve() {
  65  difference(){
  66   belt_guide_base(1);
  67   belt_guide_holes(1);
  68  }
  69 }
  70
  71 belt_guide();
  72
  73 translate([flange_d+5,0,0]) belt_guide_sleeve();