Process for manufacturing a load-bearing structure for tailgates of vehicles by thermoforming, the process comprises obtaining a thermoforming press comprising a male mold and a female mold, wherein the male mold and the female mold comprise variable maximum distances between the male mold and the female mold, heat a sheet of thermoplastic material with dimensions equivalent to the load-bearing structure for tailgates of vehicles, cooling down the male mold and the female mold, placing the sheet of thermoplastic material between the male mold and the female mold, adjusting the male mold and the mold female causing the pressing of the sheet of thermoplastic material to obtain the load-bearing structure and dimensionally stabilize the load-bearing structure.

A method of manufacturing a structure is provided in which a burr portion can be more reliably cut. In a burr portion shaping step, the burr portion is sucked to an engaging portion by a suction part to shape the burr portion along the engaging portion, and in a cutting step, ae movable portion is moved relative to first and second split molds with the burr portion being shaped along the engaging portion, thereby the burr portion is cut from a molded main body along a cutting line.

The invention relates to a process for producing multidimensional rigid foam parts.

A method of manufacturing a structure in which a burr portion can be more reliably cut. In a burr portion shaping step, the burr portion is sucked to an engaging portion by a suction part to shape the burr portion along the engaging portion, and in a cutting step, ae movable portion is moved relative to first and second split molds with the burr portion being shaped along the engaging portion, thereby the burr portion is cut from a molded main body along a cutting line.

A method includes forming a plastic shell that has a hollow feature that includes a cavity. The method further includes inserting an object into the cavity, wherein the object is in a solid state and is preformed and shaped to fit into the cavity prior to the inserting of the object into the cavity, wherein the object provides structural strength to the plastic shell at a location of the hollow feature and does not interfere with a fit of the plastic shell onto a dental arch of a patient, the object having a shape that substantially matches a contour of the cavity prior to being inserted into the plastic shell.