// VARS
old_fan_depth=38;
fan_dia=80;
fan_depth=25;
fan_oversize=10;
mt=2.5;
width=fan_dia;
length=fan_dia;
hole_dia=4.25;
hole_offset=4.5;
depth=old_fan_depth-fan_depth;
cage_mt=2;
$fn=100;

//##################

// MODEL

module bracket_bottom(){
    difference(){
        cube([width,length,mt]);
        translate([fan_dia/2,fan_dia/2,-0.1])cylinder(r=(fan_dia+fan_oversize)/2,h=depth+0.2);
        translate([-0.1,length/2+0.1,-0.1])cube([width+0.2,(length+0.1)/2,depth+0.2]);
        translate([length/2,hole_offset,-0.1]){
            translate([-length/2+hole_offset,0,0])cylinder(r1=hole_dia/2,r2=hole_dia/2+0.5,h=mt+0.2);
            translate([length/2-hole_offset,0,0])cylinder(r1=hole_dia/2,r2=hole_dia/2+0.5,h=mt+0.2);
        }
    }
    translate([-cage_mt,-mt,0])cube([length+cage_mt*2,mt,depth]);
}

bracket_bottom();