Plastic shaping was performed by means of the combination of IR heating and pellet softening in a semitransparent open mold. Three commercial thermoplastic materials were employed (acrylonitrile-butadiene-styrene, polyethylene, and polypropylene) and process curves were extracted depending on IR lamp power and interaction time. A simple exponential model was defined for the prediction of molded sample thickness and a master curve was built for all the materials. A scale factor was introduced depending on the IR lamp power and not on the material. Besides, the density of molded sample was monitored, obtaining in such conditions density values comparable to typical injection molded ones, even if a very low load was applied during pellet molding (10 N).