Abstract: A lightweight thermoplastic core, formed from ThermoPlastic Olefin/ThermoPlastic Vulcanite (TPO/TPV) sheet machined. Said sheet is made of a TPO material that contains fillers to enhance strength and improve Coefficient of Linear Expansion (CLTE). The sheet is heated to thermoforming temperature, then formed by pressure-forming or mechanical pressing the desired shape (truss shape), forming a multi-dimensional core. Said core now is several times thicker than the input sheet. The new-formed core still has sufficient surface area to provide a sufficient bond to produce a structural panel. The core also utilizes the shape or wall formed in the Vertical Plane to create Vertical columns similar to honeycomb. The core is of sufficient strength as to handle compressive loads on all three axes: x, y, and z. Said core is ideal for application in the transportation and RV industries.