module fudge_plus(l) {
    union() {
        hull() {
            translate([-l*0.3,0,0]) sphere(l/10);
            translate([l*0.3,0,0]) sphere(l/10);
        }
        hull() {
            translate([0,-l*0.3,0]) sphere(l/10);
            translate([0,l*0.3,0]) sphere(l/10);
        }
    }
}

module fudge_minus(l) {
    hull() {
        translate([0,-l*0.3,0]) sphere(l/10);
        translate([0,l*0.3,0]) sphere(l/10);
    }
}