Injection molding is simply forcing a melted thermoplastic into a mold of some sort, letting it cool, and then prying the mold apart to get to the finished piece. Hot glue guns are basically handheld ...
The following is an edited excerpt from The Business of Injection Molding, by Clare Goldsberry. The book is the first title in the IMM Book Club Injection Molding Management Series, published by IMM.