While this thread is about the making of a hand plane which is usually discussed as a "Neanderthal" tool here at SMC when you get into the nitty-gritties, I think the video I'm linking to will have broad interest. Lie Nielsen posted this really interesting video on the 'Tube of how they make the low angle jack which many of us own (or own similar) even when we primarily use power tools. It's a nice mix of old school casting in the beginning through many iterations of precision machining along with actual hands-on by humans. It's kinda kewel how that crusty looking initial casting "blossoms" into the shiny and sharp thang by the end of the process. There is some bonus "shaving porn" at the very end.