The metric system sucks
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From: jmfbahciv on 14 Feb 2010 09:23 J. Clarke wrote: > 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. > > I'm thinking about how drills changed over the years _before_ electricity. I don't remember ever seeing hand drills with the option of changing the bits. Do you know the ones I'm talking about? You held the shaft with both hands and rotated; the shaft looked like a step-function graph. /BAH
From: jmfbahciv on 14 Feb 2010 09:27 Andrew Usher wrote: > 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? Because you have no use for one system vs another system. Which measurement system you use all depends on what you're trying to accomplish. > >>>> 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. > there is a term in psychology for that kind of thinking; can't recall the word right now. Bottom line is that you have an inability to think with objectivity. Your opinion of the metric system indicates that you haven't needed it nor used it nor had to do calculations involving the physical world. /BAH
From: Matt on 14 Feb 2010 11:18 On Sun, 14 Feb 2010 09:27:26 -0500, jmfbahciv wrote: >Your opinion of the metric system indicates that you haven't >needed it nor used it nor had to do calculations involving >the physical world. Why does ease of calculation get so much weight in this discussion? How do the design and construction budgets compare for most projects? Given that the designer may be paid at a higher rate than the construction worker, the distribution in labor hours is skewed even more. So one nerd has to take an extra minute to actually think about what he is doing when working in units that are convenient to the tradesmen. But multiple tradesmen are going to be using the designer's document in the real world for months. The must-be-metric-for-white-collar-convenience argument seems self-serving.
From: Matt on 14 Feb 2010 11:48 On Sun, 14 Feb 2010 09:23:15 -0500, jmfbahciv wrote: >J. Clarke wrote: >> 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. >> >> >I'm thinking about how drills changed over the years _before_ >electricity. I don't remember ever seeing hand drills with >the option of changing the bits. Do you know the ones I'm >talking about? You held the shaft with both hands and rotated; >the shaft looked like a step-function graph. Do you recall drills _before_ electricity? Why are they an issue? There are hand drills with 3-jaw chucks. You're talking about a "brace and bit." http://en.wikipedia.org/wiki/Brace_(tool) You correctly used the work "bit" but confused it with "drill." Notice that drill sizes, like electronic resistor values, are generally not equally spaced. One is quite unlikely to say, "That drill would make a larger hole than I need. I think I'll use a drill one-tenth that size." The whole factor-of-ten thing in the pro-metric argument is about convenience expressing orders of magnitude. It has little to do with the magnitude of an adjustment one might make in the real world when deciding how much of something to use for a particular application. Am I going to fill my gas tank with ten times the amount of fuel because it is measured in metric units? No. A typo in a power of ten may go unnoticed quite easily. If one omits the conversion from yards to feet, the result is off by a factor of three; possibly within the safety factor of the design. If one improperly omits "kilo", the result is off by a factor of one thousand; probably beyond the safety factor of the design.
From: Andrew Usher on 14 Feb 2010 12:10
Matt wrote: > 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 <snip> > I see nothing inherent in a meter to recommend it over a cubit. No, surely not. And I have nothing against the cubit. It just seems redundant to the foot, which may be why it fell out of use. > 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 100C. But > the Celsius scale makes it easier for tabletop chemists to calibrate > their thermometers. No, it doesn't, actually. If you want to measure the boiling of water, it isn't any harder to use 212 F as 100 C - and you have to correct for pressure anyway, to be accurate enough for calibration. Andrew Usher |