Instruct: Classify Amazon reviews into positive or negative sentiment
Query: Best extrusion book I've read

Let me preface this review by saying that this book is meant for those with an engineering degree or strong technical background. The text quickly moves into derivations for the analysis of extrusion equipment; and without this background one will easily be lost in the math. That being said, it has pretty much everything a practicing extrusion engineer would need. I haven't had the chance to read through the entire book, however thus far have found the screw design quite helpful in the understanding of the process (as a working engineering in plastic extrusion). Despite having an engineering degree, I do find myself getting lost in the derivations, however this is true with almost any technical reference book. Take your time and this book can prove quite useful in extrusion design/troubleshooting.