$fn=64;

// --- Parameters ---
bin_height = 36;            // 3-unit height as requested
outer_radius = 35;          // Sized for medium parts (~60mm flat-to-flat)
wall_thickness = 1.6;       // Standard 3D printing wall thickness
bottom_thickness = 1.6;     // Standard 3D printing bottom thickness

// Calculate inner radius to maintain uniform wall thickness on a hexagon
inner_radius = outer_radius - (wall_thickness / cos(30));

// --- Main Model ---
difference() {
    // Outer hexagonal shell
    cylinder(h=bin_height, r=outer_radius, $fn=6);
    
    // Inner cavity cutout
    // Z-height extended by 1mm to ensure a clean manifold difference at the top
    translate([0, 0, bottom_thickness])
        cylinder(h=bin_height - bottom_thickness + 1, r=inner_radius, $fn=6);
}