Bedside clip-on shelf tray for bed. Customizable

// Parametric Bed Shelf Design - v21
// Optimized for printing on its side without supports on a Bambu Lab A1 Mini (180x180x180mm)

/* [Main Dimensions] */
// Total horizontal shelf length/depth
total_shelf_length = 195; // [100:1:280]
// Width of the shelf along the bed wall (extrusion length)
shelf_width = 175; // [50:1:280]
// Thickness of the bed headboard/wall
bed_wall_thickness = 37; // [5:1:100]
// General wall thickness for structural strength
wall_thickness = 6; // [1:1:15]
// Thickness of the shelf plate and top connector
shelf_thickness = 8; // [1:1:15]

/* [Hook/Clamp Dimensions] */
// Depth of the hook clamp on both sides (making both walls the same height)
hook_depth = 65; 
// Chamfer size for the bottom tips of the clamp walls (flat-bottomed chamfer)
wall_chamfer = 2;
// Toggle to enable chamfers in the inner corners of the hook slot
enable_hook_chamfer = false;

/* [Support Brace] */
// Thickness of the support brace
brace_thickness = 6;
// Horizontal extension of the brace under the shelf
brace_depth = 60;
// Vertical extension of the brace on the middle wall
brace_height = 45;
// Chamfer size for the support brace angles
brace_chamfer = 2;

/* [Tray/Recess Options] */
// Toggle to enable the recessed tray (raised lip). Set to false for a flat top shelf.
enable_tray = true;
// Toggle to make the shelf outer corners chamfered (45 deg) or square (90 deg)
chamfer_shelf_corners = true;
// Chamfer size for the outer shelf corners
corner_radius = 12;
// Width of the raised lip around the shelf
lip_width = 4;
// Depth of the recess (tray pocket)
recess_depth = 2;
// Bevel/chamfer width for the sloped inner edge of the lip
recess_bevel_width = 2;
// Chamfer size for the shelf outer edge profile (flat-front chamfer)
fillet_radius = 2;

/* [Calculated Parameters] */
hook_total_width = bed_wall_thickness + 2 * wall_thickness;
shelf_projection = total_shelf_length - hook_total_width;

module profile2D() {
    // 1. Shelf plate with chamfered outer edge (flat-front chamfer)
    polygon([
        [0, 0],
        [-shelf_projection + fillet_radius, 0],
        [-shelf_projection, -fillet_radius],
        [-shelf_projection, -shelf_thickness + fillet_radius],
        [-shelf_projection + fillet_radius, -shelf_thickness],
        [0, -shelf_thickness]
    ]);

    // 2. Middle wall (extending up to Y = 0, with flat-bottomed chamfer)
    polygon([
        [0, 0],
        [wall_thickness, 0],
        [wall_thickness, -hook_depth + wall_chamfer],
        [wall_thickness - wall_chamfer, -hook_depth],
        [wall_chamfer, -hook_depth],
        [0, -hook_depth + wall_chamfer]
    ]);

    // 3. Top connector (thickness controlled by shelf_thickness)
    translate([wall_thickness, -shelf_thickness])
        square([bed_wall_thickness, shelf_thickness]);

    // 4. Inner flap (with flat-bottomed chamfer and top-right chamfer)
    difference() {
        polygon([
            [hook_total_width - wall_thickness, 0],
            [hook_total_width, 0],
            [hook_total_width, -hook_depth + wall_chamfer],
            [hook_total_width - wall_chamfer, -hook_depth],
            [hook_total_width - wall_thickness + wall_chamfer, -hook_depth],
            [hook_total_width - wall_thickness, -hook_depth + wall_chamfer]
        ]);
        // Subtract top-right corner chamfer (3mm)
        translate([hook_total_width, 0])
            polygon([
                [0, 0],
                [-3, 0],
                [0, -3]
            ]);
    }

    // 5. Support brace (gusset) - clean diagonal bar with chamfered inner corners
    theta = atan((brace_height - shelf_thickness) / brace_depth);
    
    // Chamfer points
    V1_shelf = [-brace_depth + brace_chamfer, -shelf_thickness];
    V1_diag  = [-brace_depth + brace_chamfer * cos(theta), -shelf_thickness - brace_chamfer * sin(theta)];
    V2_diag  = [-brace_chamfer * cos(theta), -brace_height + brace_chamfer * sin(theta)];
    V2_wall  = [0, -brace_height + brace_chamfer];
    
    V3 = [0, -brace_height - brace_thickness / cos(theta)];
    V4 = [-brace_depth - brace_thickness / sin(theta), -shelf_thickness];
    
    polygon([V1_shelf, V1_diag, V2_diag, V2_wall, V3, V4]);

    // 6. Corner chamfer inside the support brace triangle (shelf bottom to middle wall)
    polygon([
        [0, -shelf_thickness],
        [-brace_chamfer, -shelf_thickness],
        [0, -shelf_thickness - brace_chamfer]
    ]);

    // 7. Hook inner corner chamfers (optional)
    if (enable_hook_chamfer) {
        polygon([
            [wall_thickness, -shelf_thickness],
            [wall_thickness + brace_chamfer, -shelf_thickness],
            [wall_thickness, -shelf_thickness - brace_chamfer]
        ]);
        polygon([
            [hook_total_width - wall_thickness, -shelf_thickness],
            [hook_total_width - wall_thickness - brace_chamfer, -shelf_thickness],
            [hook_total_width - wall_thickness, -shelf_thickness - brace_chamfer]
        ]);
    }
}

module footprint2D() {
    union() {
        // Shelf footprint (chamfered or square)
        if (chamfer_shelf_corners) {
            polygon([
                [0, 0],
                [0, shelf_width],
                [-shelf_projection + corner_radius, shelf_width],
                [-shelf_projection, shelf_width - corner_radius],
                [-shelf_projection, corner_radius],
                [-shelf_projection + corner_radius, 0]
            ]);
        } else {
            translate([-shelf_projection, 0])
                square([shelf_projection, shelf_width]);
        }
        
        // Hook footprint (straight rectangle)
        translate([0, 0])
            square([hook_total_width, shelf_width]);
    }
}

module recess2D(offset_val = 0) {
    x_min = -shelf_projection + lip_width;
    x_max = hook_total_width; // Extended to the very back of the inner flap (no back lip)
    z_min = lip_width;
    z_max = shelf_width - lip_width;
    c_size = corner_radius - lip_width;

    // Shift coordinates by offset_val
    x_min_offset = x_min + offset_val;
    x_max_offset = x_max; // Open on bed side, no shift
    z_min_offset = z_min + offset_val;
    z_max_offset = z_max - offset_val;
    
    // Scale the chamfer size based on offset geometry:
    // c'_size = c_size - offset_val * (sqrt(2) - 1)
    c_size_offset = c_size - offset_val * (sqrt(2) - 1);

    if (chamfer_shelf_corners && c_size_offset > 0) {
        polygon([
            [x_max_offset, z_min_offset],
            [x_max_offset, z_max_offset],
            [x_min_offset + c_size_offset, z_max_offset],
            [x_min_offset, z_max_offset - c_size_offset],
            [x_min_offset, z_min_offset + c_size_offset],
            [x_min_offset + c_size_offset, z_min_offset]
        ]);
    } else {
        polygon([
            [x_max_offset, z_min_offset],
            [x_max_offset, z_max_offset],
            [x_min_offset, z_max_offset],
            [x_min_offset, z_min_offset]
        ]);
    }
}

module beveled_recess3D() {
    // We create a beveled 3D shape by taking the convex hull of two offset 2D slices at different heights.
    hull() {
        // Top slice (larger, slightly above Y=0 to avoid z-fighting)
        rotate([90, 0, 0])
            translate([0, 0, -0.1])
                linear_extrude(height = 0.1) {
                    recess2D(0);
                }
        // Bottom slice (smaller, offset inwards by recess_bevel_width at Y = -recess_depth)
        rotate([90, 0, 0])
            translate([0, 0, recess_depth])
                linear_extrude(height = 0.1) {
                    recess2D(recess_bevel_width);
                }
    }
}

module bed_shelf() {
    difference() {
        // Solid body: intersection of profile and footprint
        intersection() {
            // Extrude profile in Z
            linear_extrude(height = shelf_width) {
                profile2D();
            }
            // Extrude footprint in Y and rotate to align
            rotate([90, 0, 0])
                linear_extrude(height = 2 * hook_depth, center = true) {
                    footprint2D();
                }
        }
        
        // Recessed tray subtraction (with sloped inner walls)
        if (enable_tray) {
            beveled_recess3D();
        }
    }
}

// Center the shelf in XY and rotate it by 55 degrees around Z
// to maximize print area usage on the Bambu Lab A1 Mini (180x180x180mm).
// 55 degrees is the mathematically optimal angle for this asymmetric geometry,
// minimizing the bounding box and leaving equal clearance on both sides.
rotate([0, 0, 55])
    translate([-(-shelf_projection + hook_total_width)/2, hook_depth/2, 0])
        bed_shelf();