Bill [Hammack] details the key engineering principles underlying plastic injection molding. He describes its history and then reveals the intricate details of the process. He shows viewers where to found, on any injection-molding product, the markings created by injection molding. He closes with a description of the one of the finest examples of the injection molding: the Lego brick.
After we watched this Engineer Guy video, the kids ran for a few LEGO pieces and studied them for the injection point and ejector pin witness marks. We also watched this suggested How It’s Made video:Follow this with Inside the LEGO Factory: How robots & machines make LEGO. Plus: Ocean Confetti, the challenge of micro-plastics and the 16 year old that turned banana peels into a biodegradable bioplastic.