I’ve gathered most of what I’ve learned about Japanese gimlets into one drawing. Sources are “Japanese Woodworking Tools: Their spirit, tradition, and use” by Toshio Odate, an image shared on lumberjocks.com, a handful of videos, and a little bit of experience.

The column drill guide is especially clever; I saw someone using one to drill a hole pattern in wood. I imagine early machinists/locksmiths/engineers were operating similar contraptions a long time before people realized how useful coordinate-based machining could be. When the flywheel is used as depth stop, it has the fundamental elements of a milling machine.