disposable-rocket-fins.scad

   1 eps = 0.01;
   2 infty = 1000;
   3
   4 motor_diam = 18;
   5 wall = 1.5;
   6
   7 cyl_h = 30;
   8 clip_angle = 40;
   9
  10 module fin() {
  11         assign(h1 = cyl_h, h2 = 20, h_off = 50, w = 30, fin_w = 1.0)
  12         translate([0, -fin_w/2, 0])
  13         hull() {
  14                 cube([eps, fin_w, h1]);
  15                 translate([w, 0, h_off])
  16                         cube([eps, fin_w, h2]);
  17         };
  18 };
  19
  20 module body() {
  21         difference() {
  22                 cylinder(r = motor_diam/2 + wall, h = cyl_h);
  23                 translate([0, 0, -infty/2])
  24                         cylinder(r = motor_diam/2, h = infty);
  25                 for (a = [-clip_angle/2, clip_angle/2])
  26                         rotate([0, 0, a])
  27                         translate([0, -wall/2, cyl_h/2])
  28                                 cube([infty, wall, infty]);
  29         };
  30
  31         for (a = [60, 180, 300]) {
  32                 rotate([0, 0, a])
  33                 translate([motor_diam/2 + wall/2, 0, 0])
  34                         fin();
  35         };
  36
  37         translate([motor_diam/2 + wall + 3, 0, 0])
  38                 difference() {
  39                         union() {
  40                                 cylinder(r = 3 + wall, h = 5);
  41                                 translate([-3 -wall, -3 -wall, 0])
  42                                         cube([3 + wall, 6 + 2*wall, 5]);
  43                         };
  44                         translate([0, 0, -infty/2])
  45                                 cylinder(r = 3, h = infty);
  46                 };
  47 };
  48
  49 body();
  50