stock_color = "#aaa4";

bushing_od = 12;
bushing_id = 8;
bushing_len = 8;

nema17_face = 42.3;

module colorize(colorname) {
  if (use_colors) {
    color(colorname) union() { children(); }
  } else {
    children();
  }
}

module bushing() {
  colorize(stock_color) render() {
    difference() {
      cylinder(d = bushing_od, h = bushing_len);
      translate([0,0,-1])
	cylinder(d = bushing_id, h = bushing_len + 2);
    }
  }
}

// located with the shaft in +z, face on the XY plane 
module nema17(depth = 23.5) {
  face = 42.3;
  screw_pitch = 31 / 2;
  color(stock_color)
    render()
  difference() {
    union() {
      translate([-face/2, -face/2, -depth])
	cube([face, face, depth]);
      translate([0,0,-1]) {
	cylinder(d=22, h=2+1);
	cylinder(d=5, h=22+1);
      }
    }
    translate([1.25, -5, 4])
      cube([10, 10, 20]);

    // screw holes
    for (x = [-screw_pitch, screw_pitch],
	   y = [-screw_pitch, screw_pitch]) {
      translate([x,y,-10])
	cylinder(d=5,h=20);
    }
  }

}