$fn=50;
hight=24;
pinScale = 1.5;
difference() {    
    union() {
        translate([0,-2.5,0])
            cube([46,35,4]);
        translate([46-4,-2.5,0])
            cube([4,35,hight+6],center=false);        
        translate([0,0,hight])
            rotate([45,0,0])
            translate([46/2,45/2,2])
            rotate([0,0,180])
            union(){
                //top pair of points
                translate([23-2,-45/2+2*pinScale,5]) 
                scale([1,pinScale,1])
                cylinder(h=10, r=2, center=true);
                translate([-23+2,-45/2+2*pinScale,5]) 
                scale([1,pinScale,1])
                cylinder(h=10, r=2, center=true);
                //bottom pair of points
                translate([23-2,45/2-2*pinScale,5]) 
                scale([1,pinScale,1])
                cylinder(h=10, r=2, center=true);
                translate([-23+2,45/2-2*pinScale,5]) 
                scale([1,pinScale,1])
                cylinder(h=10, r=2, center=true);
                
                difference() {
                    translate([0,0,1])
                    cube([46,45,6], center=true);
                    translate([0,0,2]) {
                        cylinder(h=4, r=23, center=true);
                        cylinder(h=8, d=16, center=true);
                        cube([40-2,60,4], center=true);
                        translate([16,0,]) 
                        cube([14,13,8],center=true);
                    }
                }
            }
    }
    translate([3+10-1,5,0])
    cube([30,20,4]);
}