infty = 100;
eps = 0.01;

base_h = 3;
base_d = 39;

tube_d1 = 27.5;
tube_h1 = 8;

tube_d2 = 23.5;
tube_h2 = 12;

tube_wall = 2;

// rotate([90, 0, 0])
difference() {
	union() {
		difference() {
			cylinder(r = base_d/2, h = base_h, $fn = 128);
			translate([0, 0, base_h/2])
				cylinder(r1 = base_d/2-2, r2 = base_d/2-1,
					h = base_h/2+eps, $fn = 128);
		}
		translate([0, 0, base_h/2-eps])
			cylinder(r1 = tube_d1/2+1, r2 = tube_d1/2,
				h = base_h/2+eps, $fn = 128);
		cylinder(r = tube_d1/2, h = base_h + tube_h1, $fn = 6);
		cylinder(r = tube_d2/2, h = base_h + tube_h1 + tube_h2, $fn = 6);
	}
	translate([0, 0, base_h])
	 	cylinder(r = tube_d2/2-tube_wall, h = tube_h1 + tube_h2 + eps, $fn = 6);
	// for debugging
	// translate([-infty/2, 3, -eps]) cube(infty);
	// translate([-infty/2, -3-infty, -eps]) cube(infty);
}