fivemack | (no subject)

I've recently been trying some woodwork. If I want a cube of wood 33 millimetres on a side, I buy a stick of wood hat has been planed down to 33 millimeters on a side with square corners, I set up a mitre saw, I make two pencil marks 33mm apart on the edge of the wood, put the wood on a flat table and extend the marks across the side of the wood using a square resting on the table. I make sure the blade is in the same position relative to the mark each time I cut. I clamp the bar of wood to the back of the saw housing in two places, and I cut twice. If I've been careful the cube is 33mm rather than 34mm.

I believe that a competent metalworker could make a metal cube 33.00 millimeters on a side, I've read about Fabry-Perot etalons which are essentially glass blocks with one dimension precisely 33.0000 millimeters. Where would I look for information at the boringly-detailed level of accuracy that I gave for woodwork of how these extra orders of accuracy are obtained?

I suppose I'm looking for information at a grade that would satisfy a six-year-old's sense of recursive questioning - yes, you measure it with a micrometer, but how did you make the micrometer and ensure it was accurate. I guess this is a one-term module taken in the first year of a mechanical engineering degree, but what's the best textbook for that course?

Flat | Top-Level Comments Only

I have no knowledge of woodwork or metalwork, but the mention of cutting cubes of wood caught my attention, because my father made some attempts at that. Are you by any chance trying to make burr puzzles or soma cubes or 3d pentominoes?

I was initially thinking of making a Menger sponge (http://en.wikipedia.org/wiki/Menger_sponge), but that turns out to be particularly difficult; at the moment I've reached a frustrating stage in making what's basically a Greek-key design (eighteen 45-degree mitre joints to have a line wander around a cube in an interesting way).

Grandad made me a burr puzzle and some 3d pentominoes when I was very small, and I'm not quite sure where they are now, which is a pity.

Oh, dear. Problem made for additive technology, I think.