Abstract: There is disclosed an apparatus and method for forming a honeycomb core. In particular, the apparatus comprises a compressible array of heater rods that are interleaved with layers of a formable material. Upon compressing the array, the formable material conforms to the shape of the heater rods. Through the application of heat and pressure, the different layers of the formable material are caused to bind to each other. The bound layers thereby form a honeycomb core, which is then removed from the forming apparatus. Also disclosed herein are methods of making honeycomb core using the apparatus, as well as methods of determining precise curing conditions for the making of honeycomb core, by sensing the temperature and pressure transmitted to the formable materials during the curing process.