Tighter fit small gears

I found that the motor shaft cutout on the small gears was far too big for the 28BYJ-48 5 volt stepper motors from Amazon. I modified the gears.scad file to reduce the cutout diameter, reduce the width across the flats, and increased the contact area height to be the full gear height (originally around half gear height). The gears.scad file is attached.

The printer was a Creality Ender-3 Pro V2 using PLA+ filament, sliced in Cura.

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Ah, I can’t attach a file. Here’s the modified section of gears.scad:

module motor_shaft_cut_out(h){    
    flat_h=h-1.5;
    shaft_r=4.3/2*1.1;
    intersection(){
        cylinder(r=shaft_r, h=999, center=true);
        sequential_hull(){
            translate_z(-tiny()){
                cube([999,2.3,tiny()]*1.1,center=true);
            }
            translate_z(flat_h){
                cube([999,2.3,tiny()]*1.1,center=true);
            }
            translate_z(flat_h+2){
                cube([999,6,tiny()]*1.1,center=true);
            }
            translate_z(999){
                cube([999,6,tiny()]*1.1,center=true);
            }
        }
    }
    //chamfer the top/bottom for better fit
    translate_z(h){
        cylinder(r1=shaft_r,r2=shaft_r+2,h=2,center=true);
    }
    cylinder(r2=shaft_r,r1=shaft_r+2,h=2,center=true);
}