$fn=64;

// --- Parameters ---
inner_dia = 155;           // Fits 6-inch container (152.4mm) with clearance
wall_thickness = 8;        // Heavy duty wall thickness
height = 45;               // Total height of the ring
stack_depth = 10;          // Depth of the stacking joint
tolerance = 0.6;           // Radial clearance for stacking
rib_count = 32;            // Number of aesthetic outer ribs
channel_count = 4;         // Number of cross-cuts for water channels (8 total openings)
channel_width = 12;        // Width of water management channels

// --- Derived Dimensions ---
inner_r = inner_dia / 2;
outer_r = inner_r + wall_thickness;
mid_r = inner_r + (wall_thickness / 2);

// --- Main Model ---
difference() {
    union() {
        // Main ring body
        cylinder(h=height, r=outer_r);
        
        // Aesthetic reinforcing ribs
        for(i = [0 : rib_count - 1]) {
            rotate([0, 0, i * (360 / rib_count)])
            translate([outer_r - 1, 0, height / 2])
            cylinder(h=height - (stack_depth * 2), r=2.5, center=true);
        }
    }
    
    // Main inner container cutout
    translate([0, 0, -1]) 
        cylinder(h=height + 2, r=inner_r);
        
    // Top stacking recess (cuts into the inside of the wall)
    translate([0, 0, height - stack_depth]) 
        cylinder(h=stack_depth + 1, r=mid_r + tolerance);
        
    // Bottom stacking recess (cuts into the outside of the wall)
    translate([0, 0, -1]) 
        difference() {
            cylinder(h=stack_depth + 1, r=outer_r + 2);
            translate([0, 0, -1]) 
                cylinder(h=stack_depth + 3, r=mid_r - tolerance);
        }
        
    // Integrated water management channels (bottom cutouts)
    for(i = [0 : channel_count - 1]) {
        rotate([0, 0, i * (180 / channel_count)])
        translate([0, 0, stack_depth / 2 - 1])
        cube([outer_r * 2.5, channel_width, stack_depth + 2], center=true);
    }
}