--- /dev/null
+$fn=8;
+
+diameter = 30;
+height = 20;
+
+difference() {
+ cylinder(h=height, d=7, $fn=32);
+ cylinder(h=height, d=4, $fn=32);
+}
+//cylinder(h=1 , d=10, $fn=32);
+
+difference() {
+ cylinder(h=height, d=diameter+8);
+ cylinder(h=height, d=diameter+0);
+}
+
+difference() {
+for (h = [0 : 1 : height-2]) {
+for (i = [0 : 4 : 180]) {
+ translate([0,0,1+h]) rotate([90,0,i+(h*3)]) cube([0.2,0.2,diameter+3], center=true);
+}
+}
+cylinder(h=height, d=4, $fn=32);
+}
\ No newline at end of file