$fn=64;

// --- Parameters ---
can_diameter = 68;       // Standard spray paint can is ~65-68mm
clearance = 2;           // Clearance for easy insertion
wall_thickness = 3.5;    // Thickness of the rack walls
rack_height = 60;        // Overall height of the rack
base_thickness = 3;      // Bottom thickness
num_cans = 3;            // Number of slots in the rack

// --- Calculated Variables ---
hole_d = can_diameter + clearance;
outer_d = hole_d + (wall_thickness * 2);
spacing = outer_d - wall_thickness; // Overlap to merge walls between slots

// --- Main Geometry ---
difference() {
    // Outer Body
    hull() {
        for(i = [0 : num_cans - 1]) {
            translate([i * spacing, 0, 0])
                cylinder(d=outer_d, h=rack_height);
        }
    }

    for(i = [0 : num_cans - 1]) {
        // Main cylinder cutout for the can
        translate([i * spacing, 0, base_thickness])
            cylinder(d=hole_d, h=rack_height + 1);
            
        // Front viewing/access slot (allows seeing the can label/color)
        translate([i * spacing, -outer_d/2, base_thickness + 15 + rack_height/2])
            cube([hole_d * 0.65, outer_d, rack_height], center=true);
            
        // Bottom material-saving / push-out hole
        translate([i * spacing, 0, -1])
            cylinder(d=hole_d * 0.5, h=base_thickness + 2);
            
        // Wall mounting screw holes in the back wall
        translate([i * spacing, outer_d/2, rack_height - 15])
            rotate([90, 0, 0])
            cylinder(d=5, h=wall_thickness * 4, center=true);
            
        // Screw head countersink/clearance
        translate([i * spacing, outer_d/2 - wall_thickness + 1, rack_height - 15])
            rotate([90, 0, 0])
            cylinder(d=10, h=wall_thickness * 2, center=true);
    }
}