Techniques for producing panels such as for use in a vehicle, boat, aircraft or other transport structure or mechanical structure using a 3-D-printed tooling shell are disclosed. A 3-D printer may be used to produce a tooling shell containing Invar and/or some other material for use in molding the panels. A channel may be formed in a 3-D printed tooling shell for enabling resin infusion, vacuum generation or heat transfer. Alternatively, or in addition to, one or more hollow sections may be formed within the 3-D printed tooling shell for reducing a weight of the shell. The panel may be molded using the 3-D printed tooling shell.