difference(){
    cube([100,100,100]);
    rotate([0,27,0])translate([-100,0,0])cube([100,100,150]);
    translate([100,0,0])rotate([0,-27,0])cube([100,100,150]);
    translate([0,100,0])rotate([27.5,0,0])cube([100,100,150]);
    rotate([-27,0,0])translate([0,-100,0])cube([100,100,150]);
}