These are the OpenSCAD files used to create a ZMR250 quadcopter battery cage.

battery_box_back_clip.scad

$fn=100;
module pole() {
    difference() {
        cylinder(r=4.7, h=17.4);
        translate([0,0,-1]) {
            cylinder(r=2.7, h=19.4);
        }
    }
}
difference() {
    pole();
    translate([17,0,0]){
        difference() {
            translate([0,0,-1]){
                cylinder(r=19.75, h=19.4);
            }
            translate([-23,0,-2]){
                cube([60,60,60]);
            }
        }
    }
}
translate([34,0,0]){
    pole();
};
translate([17,0,0]){
    difference() {
        cylinder(r=21.65, h=17.4);
        translate([0,0,-1]){
            cylinder(r=19.75, h=19.4);
        }
        translate([-23,0,-2]){
            cube([60,60,60]);
        }
    }
}

battery_box_front_panel.scad

$fn=100;
module pole() {
    difference() {
        cylinder(r=4.7, h=17.4);
        translate([0,0,-1]) {
            cylinder(r=2.7, h=19.4);
        }
    }
}
pole();
translate([34,0,0]){
    pole();
};
translate([0,-4.7,0]) {
    cube([34,2,17.4]);
}

battery_box_side_panel.scad

$fn=100;
module pole() {
    difference() {
        cylinder(r=4.7, h=17.4);
        translate([0,0,-1]) {
            cylinder(r=2.7, h=19.4);
        }
    }
}
pole();
translate([60,0,0]){
    pole();
};
translate([0,-4.7,0]) {
    cube([60,2,17.4]);
}