module ball() {
      difference() {
        sphere(r=10, $fn=20);
          sphere(r=9);
        cylinder(h=1, r = 10, center = true);
        rotate([0,45,0])
        cylinder(h=1, r = 10, center = true);
        rotate([0,90,0])
        cylinder(h=1, r = 10, center = true);
        rotate([0,135,0])
        cylinder(h=1, r = 10, center = true);
    }
}

module fix1() {
    translate([0, 9.5, 0])
    scale([3,1,3])
    sphere(r=1, $fn=20);
}

fix1();

module fix2() {
    translate([0, -9.5, 0])
    scale([3,1,3])
    sphere(r=1, $fn=20);
}

fix2();


ball();