// Parameters
$fn = 360;
kerf = 0.1;
width = 4 - kerf;
height = 15;
chamfer = 2;
size = 30;
module cut(width, height,chamfer){
    polygon(points=[
        [-width/2, 0],         
        [-width/2, height-chamfer],
        [-width/2-chamfer, height],
        [width/2+chamfer, height],
        [width/2, height-chamfer],
        [width/2, 0]    
    ]);
}
module piece(radius,ncuts,width,height,chamfer){
    difference(){
        circle(radius);
        for (i = [0 : 360/ncuts : 359]) { // Loop from 0 to 360 degrees
            rotate([0, 0, i])  // 2nd: Rotate the moved object around the center
                translate([0,radius-height,0])
                    cut(width,height,chamfer);
        }
    }
}
margin = 10;
translate([0, size*2+margin, 0])
    piece(size,2,width,height,chamfer);
translate([size*2+margin, size*2+margin, 0])
    piece(size,3,width,height,chamfer);
//translate([0, 0, 0])
    piece(size,5,width,height,chamfer);
translate([size*2+margin, 0, 0])
    piece(size,6,width,height,chamfer);
// adding more shapes    
translate([-size, -size *2 - margin, 0])
    square([size*4+margin, 30]);
translate([0,-size*4 - margin,0])
    polygon(points = [[-size,0],[0,size * sqrt(3)],[size,0]]);
translate([size+margin,-size*4 - margin,0])
    square(size*2-margin);