$fn = 100;

base_height = 4;
total_height = 80;
epsilon = 0.01;

difference() {
    union() {
        translate(v=[0, 0, base_height / 2]) {
            cylinder(h=base_height, d=61, center=true);
        }
        translate(v=[30.5, 0, base_height / 2]) {
            cylinder(h=base_height, d=12, center=true);
        }
        translate(v=[-30.5, 0, base_height / 2]) {
            cylinder(h=base_height, d=12, center=true);
        }
		difference() {
			translate(v=[0, 0, total_height / 2]) {
				cylinder(h=total_height, d=53, center=true);
			}
			union() {
				translate(v=[0, -30.5, 30.5 + base_height]) {
					rotate(a=[0, 90, 0]) {
						cylinder(h=100, r=30.5, center=true);
					}
				}
				translate(v=[0, -50, 50 + 30.5 + base_height]) {
					cube(100, center=true);
				}
			}
		}
    }
    union() {
        translate(v=[0, 0, 45]) {
            cylinder(h=100, d=47, center=true);
        }
        translate(v=[31, 0, base_height / 2]) {
            cylinder(h=base_height + epsilon, d=4.5, center=true);
        }
        translate(v=[-31, 0, base_height / 2]) {
            cylinder(h=base_height + epsilon, d=4.5, center=true);
        }
    }
}