$fn=64;

// --- Parameters ---
height = 72;               // 6-unit height (72mm)
outer_radius = 35;         // Outer radius (center to corner)
wall_thickness = 2;        // Wall thickness
bottom_thickness = 2;      // Base thickness

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

// --- Geometry ---
difference() {
    // Outer hexagonal body
    cylinder(h=height, r=outer_radius, $fn=6);
    
    // Inner hollow cavity for deep storage
    // Height is extended by 1mm to ensure a clean manifold cut at the top
    translate([0, 0, bottom_thickness])
        cylinder(h=height + 1, r=inner_radius, $fn=6);
}