The metric system sucks
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From: J. Clarke on 13 Feb 2010 11:12 jmfbahciv wrote: > J. Clarke wrote: >> jmfbahciv wrote: >>> Andrew Usher wrote: >>>> Bob Myers wrote: >>>> >>>>>> Drills already have interchangeable bits, >>>>> Ah, another person who's never seen the inside of >>>>> a machine shop... >>>> OK, perhaps I didn't use the right terminology; I used that which I >>>> am familiar. Nevertheless, my point stands that you don't normally >>>> need a different machine for each different size of drilling. >>> Now ask the question why that is so. >> >> I'm not sure I see the point of this particular discussion. Most >> drills have three-jaw chucks that don't really require much of the >> drill bit other than that it be round and not so big that it won't >> fit in the hole or so small that the jaws won't close on it >> (typically about a 20:1 range). Certainly no drill press I have >> owned or worked with has had any trouble with bits that are >> fractional inch sizes, metric sizes, or sizes that are pretty much >> arbitrary. >> >> There are machines that require bits with tapered shanks or that use >> collets that require shanks of a specified dimension and form, or >> that require threaded shanks, but they are relatively rare--most >> drilling is done with the bits secured in a 3-jaw chuck and 3-jaw >> chucks are measurement-system agnostic. > > The reason that 3-jaw chuck exists is to adapt to any system: US, si > or Sears. No, it's to let you use the same drill with a tiny little bit or a great big huge bit. The other option is to make the bit with a standard sized shank, which means that the bits will all have steps in them, which makes them more expensive to manufacture. >> Now if you're dealing with very small drills, circuit board drills, >> and the like, they do often have a standard shank diameter, mainly >> because their small diameter would make them difficult to handle >> otherwise (like you'd need tweezers and a magnifier to change bits) >> and there the measurement system does matter, but swapping out a >> collet takes seconds. >> > Thus, the specification of the drills included adapting to any size. > The reason for the generic is becuase there were more than one flavor. Exercise--go down to Home Depot and look at the drill bits and think about what they would have to look like if 3-jaw chucks that could take any size were not in widespread use. Note that there are very small ones and very big ones and ones in between. Then think about how such a thing would be made. Then think about why anybody in his right mind would make them that way if there was another option. Then tell us whether you still think that the existence of 3-jaw chucks has anything to do with metric vs inch. You usually come across as a very sensible person but on this particular issue you're way off base.
From: Andrew Usher on 13 Feb 2010 12:14 Matt wrote: > >Everyone knows that only SI units > >are proper so that should be 7874 kg/m^3'. > > First, let's talk about those 'proper' SI units. <snip> I assume he's satirising SI, not defending it! Andrew Usher
From: Andrew Usher on 13 Feb 2010 12:16 Matt wrote: > >I meant that it [the cubit] became obsolete without any bureaucratic compulsion. > > Do you have a cite for that? No, I'm just guessing (and I mean in Europe only). > Perhaps not so many bureaucrats when the cubit was abandoned. If it > became obsolete through a royal edict, does that affect its historical > utility? If some egomaniac king wanted to change everyone else's way > of measuring things for his convenience, that says nothing about how > useful others found the cubit to be. No, I have nothing against the cubit, if people find it useful. Andrew Usher
From: Andrew Usher on 13 Feb 2010 12:22 jmfbahciv wrote: > > > I'm an American and I have never felt the need to apologize. > > > > Well, that's because you're a woman and so never feel the need to > > apologise. > > Oh, here we go again. I've used both systems. You, obviously, > have not. And how the hell does your implication follow? > > > Why do you? > > > > _I_ don't, obviously! > > But you just stated that you do feel you have apologize. Your > whole theme is based on your unwillingness to do that action. I never said I do feel that way, only that most Americans that matter do. Andrew Usher
From: Matt on 13 Feb 2010 23:45
On Sat, 13 Feb 2010 09:16:24 -0800 (PST), Andrew Usher wrote: >No, I have nothing against the cubit, if people find it useful. http://en.wikipedia.org/wiki/Cubit A cubit is the first recorded unit of length http://www.idratherbewriting.com/2008/01/07/malcolmn-gladwell�s-blink-your-first-impression-is-usually-correct-in-complex-situations/ in Blink, Malcolm Gladwell finds that in complex situations, our initial two-second judgments are often more accurate than judgments derived from lengthy, painstaking analyses. http://content.scholastic.com/browse/article.jsp?id=1601 in general don't second-guess your first impulse. http://gladwell.com/blink/index.html There's a wonderful phrase in psychology--"the power of thin slicing"--which says that as human beings we are capable of making sense of situations based on the thinnest slice of experience. Arguably, early peoples had a thinner slice of experience than exists in the world today; but they were very practical people, else they would have died and we wouldn't be here. In thinking about "How far is it from here to there?" they came up with a cubit as a standard of measurement. Had they wasted the time to come up with a politically correct unit of length based on the distance from the equator to a pole, the opportunity cost might have literally killed them. Instead of worrying over-much about whose elbow-to-fingertip distance would be the standard for the tribe, they (or the chieftain) picked one and they got on with it. It was a unit that everyone found to be useful because (barring some misfortune), everyone had an elbow-to-fingertip "ruler" with them at all times. They weren't all the same, but a lot of them were close enough. I see nothing inherent in a meter to recommend it over a cubit. And the Celsius temperature scale is just silly. Why throw away twice the whole-number granularity afforded by the Fahrenheit scale? Or the notion that 100 tends to suggest more of a milestone than 38 as a temperature extreme for comfort? Aren't the metric zealots gaga over powers of ten? Why not use a power of ten to describe a temperature that is extreme but survivable? Sterilizers operate near 100�C. But the Celsius scale makes it easier for tabletop chemists to calibrate their thermometers. If the majority of the population were tabletop chemists, it might make sense to use the Celsius scale. But they aren't; so it doesn't. |