cabinet knob 3d model

Design a 3D printable cabinet knob with an integrated threaded stud (single-piece design). Specifications: * The knob and threaded shaft must be one solid part (no assembly, no inserts). * Thread type: Metric M6 external thread (optimized for 3D printing, with slightly loose tolerance ~0.15 mm clearance). * Thread length: 12 mm. * Add a smooth lead-in chamfer at the start of the thread for easy insertion. * Add a fillet (radius 3 mm) where the threaded shaft meets the knob for strength. Knob design: * The knob must have a smooth, rounded circular shape (spherical/dome style), similar to a classic wooden cabinet knob. * No sharp edges — soft curves only. * Diameter: 30–35 mm. * Height: 20–25 mm. * Surface should be smooth and slightly glossy in appearance (like polished wood). * Optionally include very subtle grip (light grooves), but keep the clean circular aesthetic. Manufacturing constraints: * Must be optimized for FDM 3D printing (no supports if possible).