$fn=120; pen_diameter = 11; bottom(); module bottom() { difference() { union() { cylinder(r=9, h=40); cylinder(r=19, h=6); } translate([0, 0, -1])cylinder(r=4, h=42); translate([0, 0, -1])cylinder(r=pen_diameter/2, h=39); translate([-13, 0, -0.5]) cylinder(r=2, h=20); translate([ 13, 0, -0.5]) cylinder(r=2, h=20); translate([ -20, 9, -0.5])cube([40, 20, 7]); translate([ -20, -29, -0.5])cube([40, 20, 7]); } // support translate([0, 0, 38]) cylinder(r=4.5, h=0.4); }