3D Model: Comparative Cutaway Model On A Flat Mounting Plate. Plate Size 140×60×6 Mm, With Two Circular Recesses (diameter 60 Mm, Depth 2 Mm) Side By Side And Four 4×4×6 Mm Pegs Per Recess For Mounting. Left Disc (Schwarzschild Black Hole): Diameter 60 Mm, Height 30 Mm. Perfect Sphere Of Radius 20 Mm, Surrounded By A 3 Mm Thick Shell. Remove A 90° Wedge To Show The Interior. Right Disc (Kerr Black Hole, Spin A/M≈0.6): Diameter 60 Mm, Height 30 Mm. Inner Horizon As An Oblate Spheroid (equatorial Radius 20 Mm, Polar Radius 19 Mm) With A 3 Mm Shell. Surrounding Ergosphere As A Second Oblate Spheroid (equatorial Radius 30 Mm, Polar Radius 22 Mm) With A 3 Mm Shell. Remove A 60° Wedge To Show Interior Layers. Engrave Labels On Plate Below Each Disc: “Schwarzschild” And “Kerr (a=0.6)” In 2.5 Mm High Text. Ensure Watertight, Printable Mesh (minimum Feature Size 1.2 Mm). Target 80k–120k Triangles. Make A Cool Stand With A Deep Engrave "NMI- REGGIE"