This is the first week in our multi-week series on building multirotor flying things (my wife calls them toys). The math we cover in this episode is the same if you a building a quadcopter, hexacopter, octocopter and even a tricopter. We decided to tackle the math part first because before you buy any parts you need to know what parts and what values for those parts you need. So many times people skip this step and get a mashup of parts that do not work well or maybe not even work at all without smoke. We have seen so many people talking about the values without understanding what the values mean and spreading mis-information. We hope to clear all of that up in this episode.