M3HoleDiam = 3.4;

MountSize = 40;
BodyWidth = 60;

$fn = 100;

difference() {
    MainBody();
    M3MountHoles();
    BottomZRodHoles();
}

module M3MountHoles(){
    edgeDistance = (MountSize-20)/2;

    translate([0, edgeDistance, edgeDistance]) M3Hole(40);
    translate([0, MountSize-edgeDistance, edgeDistance]) M3Hole(40);
    translate([0, edgeDistance, MountSize-edgeDistance]) M3Hole(40);
    translate([0, MountSize-edgeDistance, MountSize-edgeDistance]) M3Hole(40);
}

module BottomZRodHoles(){
    xcenter = 49;
    ycenter = MountSize/2 - 10;
    holedistance = 10.6;

    translate([xcenter + holedistance/2, ycenter + holedistance/2, 0]) rotate([0,270,0]) M3Hole(5);
    translate([xcenter - holedistance/2, ycenter + holedistance/2, 0]) rotate([0,270,0]) M3Hole(5);
    translate([xcenter + holedistance/2, ycenter - holedistance/2, 0]) rotate([0,270,0]) M3Hole(5);
    translate([xcenter - holedistance/2, ycenter - holedistance/2, 0]) rotate([0,270,0]) M3Hole(5);

    // center hole
    translate([xcenter, ycenter, 0]) rotate([0,0,0]) cylinder(h = 5, d = 10.1);
}

module M3Hole(thickness) {
    rotate([0, 90, 0])cylinder(h = thickness, d = M3HoleDiam);
}

module MainBody() {
    // left mount plate
    cube([5, MountSize, MountSize]);

    // bottom frame plate
    translate([5, 0,0 ]) cube([BodyWidth, MountSize, 5]);

    // motorholder plate
    translate([0, MountSize,0 ]) cube([40+5, 5, 40]);

    // top rod holde
    translate([BodyWidth, 10,5 ]) cube([5, 20, 30]);

    translate([BodyWidth, 10, -35 ]) cube([5, 20, 35]);
}