Origins of Precision

the lathe is basically the one machine required to kickstart the industrial revolution. (and a way to drive it ofcourse). Also, three surfaces that can be ground truely flat is also vital. i can highly recommend the youtube series "machine thinking" if you have interest in this[0], aswell as the book "the perfectionist" [0] [VIDEO] [1] [LINK]

There's a way to grind mirrors optics for optics with polishing stones that aren't even flat to the naked eye. Basically the system arrives at tiny tolerances via the process of using the system. And there's way to make three perfectly flat sharpening stones by starting with three raw pieces of natural sharpening stone, just by alternately rubbing the three stones together until they flatten each other out. Paul Sellers can teach you how to flatten a large board without a planer. He also has videos on how to get a wood plane perfectly flat using a large sharpening stone (which can be made as above or with float glass). And if memory serves, you to make something perfectly round you first need something perfectly flat. Once you have something perfectly flat and something perfectly round it's off to the races. Edit: "The Origins of Precision" is a half hour well spent [VIDEO]

This is a really nice video if you are interested in measurement precision for manufacturing: Machine Thinking: Origins of Precision and first project introduction [VIDEO]

> the precision metal tools I was wondering about how those came about not long ago, and stumbled over this[1] nice video, "Origins of Precision". [1]: [VIDEO]

How the screw of the wine press was the central part of Gensfleisch/Gutenbergs invention which allowed all the other previously existing ones to finally come together (though I also read that certain advances in metallurgy were also essential). Also see the previous video on screws, a much underappreciated invention. It then describes how the availability of books made propagation of existing technology and newer developments possible and faster. The only other comparable moments in history are probably the evolution of spoken language, the invention of writing and most recently the internet. Also much recommended from that Chanel are the videos on the "Origins of Precision"[1], and "The 1751 Machine that Made Everything"[2]. 1: [VIDEO] 2: [LINK]

From what I've seen as an amateur that is yet fascinated by mechanical engineering: iteratively work up to the precision limits with your current methods then try to find/research a (slightly) better way of measuring and/or manufacturing. Since humanity has worked up to this point over centuries/millenia, you wouldn't need to "bootstrap" it from the beginning anymore, just choose the appropriate level of (manufacturing/measuring) precision for your usecase. Otherwise start with a surface plate. Nice summary: [VIDEO] ("Origins of Precision" by "Machine Thinking")

(Hand) scraping refers to [LINK] . With two surfaces you can still have some bias (convexity/concavity) even though they appear to be relatively flat, you need three surfaces for absolute flatness. See the Whithworth Method described earlier in this topic. If you're interested in this sort of stuff and want a video introduction, see: [VIDEO]

A YouTube channel primarily dedicated to precision: [LINK] Example video: [VIDEO] I think it's fair to call these mini-documentaries.