For one thing, you definitely need the mind of a mechanical engineer to not just get through this book's content, but quite frankly, to even want to. That being said, it seems like anyone who would even give this book a second thought while wandering through a bookstore would already have the necessary mindset and interests. I'm not saying that you actually have to be a mechanical engineer in order to work through this book. I'm just saying that you have to have that particular way of thinking about the problems that these various structures can solve, if you hope to actually enjoy what this book has to offer. Personally, I'm not a mechanical engineer, I'm a software designer, and I was able to work my way through The Unofficial LEGO Technic Builder's Guide, but for me, it was a long and laborious task. While I learned a lot, one of the things I definitely got out of this book was that it wasn't for me.
The Unofficial LEGO Technic Builder's Guide starts off going over basic mechanical engineering concepts like speed, friction, traction and power and explains why you need to keep all of these concepts in mind with any mechanical project. From there, the book goes on to describe the different types of Technic pieces that have been produced, not only basic pieces like pins and gears, but also the differences between the two styles of Technic pieces that have been created, Studfull and Studless. Actually, The Unofficial LEGO Technic Builder's Guide devotes an entire chapter to the differences between Studfull and Studless and how these differences force the builder to think about their models differently.
Next, the book takes on some basic machines. It goes into showing how to build basic levers, pulleys and linkages, those basic building blocks in most complex machines. From there, the book delves into more complicated devices such as differentials, motors and how you can step up or step down between gears and what that does to the amount of work your device can produce. Before this section, titled "Mechanics," is over, The Unofficial LEGO Technic Builder's Guide will even go into building full-fledge pneumatic engines that work similarly to four-cylinder internal combustion engines ... just without the combustion part, of course.
While you can build your own motors, LEGO has produced a few of their own. The book's third part is devoted to the building system's electrical elements including the NXT, RC and, most importantly, Power Functions lines. While some time is spent on the NXT and RC series, The Unofficial LEGO Technic Builder's Guide recognizes that LEGO is trying to unify its motors with the Power Functions system and spends most of its time talking about the different parts the belong to this group and how everything works together.
Part IV of The Unofficial LEGO Technic Builder's Guide is titled Advanced Mechanics and this is where the book goes into some pretty deep designs and concepts. That being said, this is where some of the real interesting subjects are as well since anyone with a knack for this subject will want to learn as much as possible about steering, suspension and tracked vehicles. Where this section really shines though is in the chapter about transmissions. The Unofficial LEGO Technic Builder's Guide gives both in depth discussions and building instructions for everything from a variety of two-speed transmission to a three-speed, a four-speed and a 10-speed transmission. I also found it interesting that after these highly complex building projects, we also get to see a very simple design for a continuously variable transmission (CVT).
The book's last three chapters are variations on what I've seen at the end of most LEGO builder's books. In these closing sections, the author, Pawel "Sariel" Kmiec, not only talks about how to choose the models you want to build, but how to consider the scale of the model and how all of the internal mechanisms should be arranged and hidden.
Like I said at the beginning, The Unofficial LEGO Technic Builder's Guide isn't for everyone, but if you've read this review and feel truly interested in what subjects the book covers, then you are who the book has been written for.
