Shelf raiser with hexagon structure for walls

by dezzi · 2026-02-04

This is a shelf riser (legs) with sturdy hex ribs. Recommended usage: print 2 or 3 of these and screw them to a wooden shelf. Params configurable: shelf dimensions; frame depth; hex ribs depth and wall thickness, amount of hexagons in ribs; screw holes diameter. Perfectly printable at Bambu A1 mini in current sizing (175x175mm).

Open in Editor Download STL

Screenshots

Prompt

design a rectangular frame with honeycomb structure inside. frame perimeter should be rounded square. 175mm width, 175mm height

OpenSCAD Code

// Rounded Rectangular Honeycomb Frame
// Dimensions: 175mm x 175mm

// --- Parameters ---
frame_width = 175;
frame_height = 175;
frame_depth = 24;        // Thickness of the outer rim
honeycomb_depth = 8;     // Thickness of the honeycomb lattice
frame_border = 5;        // Width of the outer solid rim
corner_radius = 15;      // Roundness of the frame corners

hex_radius = 28;         // Size of individual honeycomb cells
hex_wall = 1.5;          // Thickness of the honeycomb ribs
honeycomb_seed = 48;     // Change this number to shift the pattern

// --- Screw Hole Parameters ---
show_screwholes = true;  // Toggle screwholes ON/OFF
screw_radius = 2.5;      // Radius of the hole (5mm diameter)
screw_dist_apart = 80;   // Distance between the two holes
screw_z_percent = 0.70;  // Center position at 70% of frame depth

$fn = 60;               

// --- Calculations ---
// Calculate dynamic screw height
calculated_screw_z = frame_depth * screw_z_percent;

// Generate pseudo-random offsets based on seed
seed_offsets = rands(-hex_radius, hex_radius, 2, honeycomb_seed);
offset_x = seed_offsets[0];
offset_y = seed_offsets[1];

// --- Main Render ---
union() {
    // 1. Outer Border Frame
    difference() {
        rounded_square(frame_width, frame_height, frame_depth, corner_radius);
        
        // Interior Cutout
        translate([0, 0, -1])
            rounded_square(frame_width - frame_border*2, frame_height - frame_border*2, frame_depth + 2, corner_radius - frame_border);
        
        // Optional Teardrop Screwholes
        if (show_screwholes) {
            hole_y_pos = frame_height/2 - frame_border/2;
            
            // Right Hole
            translate([screw_dist_apart/2, hole_y_pos, calculated_screw_z])
                teardrop_hole(screw_radius, frame_border + 2);
            
            // Left Hole
            translate([-screw_dist_apart/2, hole_y_pos, calculated_screw_z])
                teardrop_hole(screw_radius, frame_border + 2);
        }
    }

    // 2. Honeycomb Fill
    intersection() {
        rounded_square(frame_width - frame_border, frame_height - frame_border, honeycomb_depth, corner_radius - frame_border/2);
        
        translate([offset_x, offset_y, 0])
            honeycomb_grid(frame_width + hex_radius*2, frame_height + hex_radius*2, honeycomb_depth, hex_radius, hex_wall);
    }
}

// --- Modules ---

module teardrop_hole(r, length) {
    // Rotated to pierce through the Y-axis wall
    rotate([90, 0, 0])
    translate([0, 0, -length/2])
    hull() {
        cylinder(h=length, r=r);
        // Pointed top for support-free printing
        rotate([0, 0, 45])
            cube([r, r, length]);
    }
}

module rounded_square(w, h, z, r) {
    translate([-w/2 + r, -h/2 + r, 0])
    hull() {
        cylinder(h=z, r=r);
        translate([w - 2*r, 0, 0]) cylinder(h=z, r=r);
        translate([0, h - 2*r, 0]) cylinder(h=z, r=r);
        translate([w - 2*r, h - 2*r, 0]) cylinder(h=z, r=r);
    }
}

module honeycomb_grid(width, height, depth, r, wall) {
    x_spacing = r * 1.5;
    y_spacing = r * sqrt(3);
    
    translate([-width/2, -height/2, 0])
    for (x = [0 : x_spacing : width]) {
        for (y = [0 : y_spacing : height]) {
            y_offset = (floor(x / x_spacing) % 2 == 0) ? 0 : y_spacing / 2;
            
            translate([x, y + y_offset, 0])
            difference() {
                cylinder(h=depth, r=r, $fn=6);
                translate([0, 0, -0.5])
                    cylinder(h=depth + 1, r=r - wall, $fn=6);
            }
        }
    }
}