tissue box 3d model

Create a 3D-printable tissue box as two separate parts: a hollow box body and a snap-fit base plate. Interior: exactly 21 cm long (X), 10 cm wide (Y), 8 cm tall (Z). Wall thickness: 2 mm. Outer nominal: 21.4×10.4×8.4 cm. Top face has a centered thin rectangular slot 13 cm long (X) × 1 cm wide (Y), edges filleted 0.5 mm. Outer side walls carry an embossed Y‑tessellation: repeating Y shapes (three arms 120° apart, arm length 5 mm, arm width 1.5 mm, central circle 2 mm dia), staggered grid 8 mm spacing, raised 1.2 mm outward with 0.5 mm fillet at base. Pattern wraps seamlessly around corners; inner walls remain flat and smooth. Top face smooth. Bottom open with an interior snap-fit groove 2 mm up from edge, 1 mm deep × 1 mm wide. Base plate: 21.4×10.4 cm, 2 mm thick. Top face has a raised snap-fit ridge 1 mm tall × 1 mm wide, inset 2 mm from all edges, to mate with groove. Bottom face smooth. All parts manifold, support-free when printed upright. No springs.