junction(20.32,2);module junction(h,thickness){difference(){difference(){cube([5.5,thickness*3,h/3+thickness+h-12],center=true);translate([0,0,-thickness/2]){cube([7,thickness,h-12+h/3],center=true);}}rotate([90,0,0]){translate([0,11+(h-10)/2-(h/3+thickness+h+12)/2,0]){cylinder(h=thickness*4,r=1.6,center=true,$fn=100);}}}}