struggling to get a G1/2 nut fit on a G1/2 bolt about threadlib HOT 2 CLOSED

use <threadlib/threadlib.scad>

turns = 7;
thread="G1/2-ext";


specs = thread_specs(thread);

P = specs[0]; Rrot = specs[1]; Dsupport = specs[2];
section_profile = specs[3];
H = (turns + 1) * P;

intersection() {
    union() {
        
        thread(thread, turns=turns);
        difference() {
        translate([0, 0, -P / 2])
            cylinder(h=H, d=Dsupport, $fn=120); /*  */
        translate([0, 0, -P / 2 -1])
            cylinder(h=H+10, d=Dsupport-3, $fn=120); /*  */
        }

        difference() {
          cylinder(h=5, d=28, $fn=6, center=true);
          translate([0,0,-3.63]) tap("G1/2", turns=6);
        }
    
    }
    cube(20);
}