pot_diameter = 40;
pot_height = 50;
small_dist = 0.01;
wall_thickness = 0.8+small_dist;
number_of_holes = 6;

$fn=100;

linear_extrude(wall_thickness)
difference(){
    circle(r=pot_diameter/2);
    for (i=[0:number_of_holes-1]) {
        rotate((360/number_of_holes)*i,[0,0,1])
        translate([pot_diameter/4,0,0])
        circle(r=pot_diameter/15);
    }
    
}
linear_extrude(pot_height)
difference(){
    circle(r=pot_diameter/2);
    circle(r=pot_diameter/2-wall_thickness);
}