Share Email Facebook Twitter LinkedIn To Convert One or More Surfaces to Solids Click Modify menu > 3D Operations > Thicken. Select the surfaces you want to thicken. Press Enter. Specify a thickness for the solid. Press Enter. Related Concepts About Converting Surfaces and Meshes to 3D Solids Related Tasks To Convert Objects With Thickness to Extruded SolidsTo Convert Contiguous Surfaces That Enclose a Volume to a 3D Solid ObjectTo Convert a Mesh Object to a 3D Solid