module test(){ cylinder(8,10.5,12); translate([0,0,8]) cylinder(8,12,10.5); } difference(){ test(); translate([0,0,3]) cylinder($fn = 6, r = 3.5, h = 10); cylinder(3,9,9); } translate([0,0, 6.5]) minkowski(){ difference(){ cylinder($fn = 6, r = 3.5, h = 1.0); cylinder($fn = 6, r = 3, h = 1.0); }}