3 module bottom(dia=15) {
6 cylinder(20, dia+4, dia+4);
7 cylinder(15, dia+8, dia+8);
9 translate([0,0,3]) cylinder(21, dia, dia);
15 cylinder(20, dia+8, dia+8);
16 translate([0,0,3]) cylinder(21, dia, dia);
17 translate([0,0,15]) cylinder(6, dia+4, dia+4);
21 translate([-60,0,0]) bottom();