15 ms·
The super-slow conversion of the U.S. to metric (2025)
- jxdxbx 8mo agoThe metric systems's worse flaw was doubling down on base 10 instead of the plainly superior base 12.
- c048 8mo agoOnly in certain fields. For most interactions divide by 10 is far easier than divide by 12, and you'd end up with far, far more "eyeballed" measurements. So no, as a human being, I'm fine with base 10.
- p-e-w 8mo agoBeing able to count using fingers is more valuable than having one more prime factor.
- jabl 8mo agoYou can actually count to 12 on your fingers using one hand. Use the thumb as a pointer, then for each of your other fingers you have three joints. So 3*4=12.
- hans_castorp 8mo agoOr use a hand as a 5-bit integer, then you can count to 31 :)
- t-3 8mo agoIt's hard to actually count using more than 4 bits/hand though. The quickest methods that require the least dexterity are those that count the knuckles (which are actually used in some counting traditions, unlike binary finger-counting).
- wongogue 8mo agoIf you include the tip, you can do base 16. Let’s go hexadecimal all the way.
- timbit42 8mo agoNo. Base 16 is only divisible by 1, 2, 4, and 8, while Base12 is divisible by 1, 2, 3, 4, and 6. Of course, Base 10 is only divisible by 1, 2, and 5. Switching from Base 10 to Base 12 would be difficult. Instead we should go back in time and ensure we evolve with 6 fingers on each hand and foot.
- jxdxbx 8mo agoThis is an excellent compromise
- deleted 8mo ago[deleted]
- JamesTRexx 8mo agoThis is why men are superior to women, we can always count to one higher. (or two including the tip, as someone suggested with the fingers) :-p ducks
- adornKey 8mo agoBut all the techniques to multiply numbers with your fingers are more confusing in base 12. https://www.wikihow.com/Multiply-With-Your-Hands https://www.wikihow.com/Multiply-With-Your-Hands Those techniques can be useful. If you add toes, multiplying numbers up to 20 (like 16x18) is easy.
- jabl 8mo agoAs long as we count in base 10, it makes sense for the unit system to also be based on base 10. As for changing the world to counting in base 12, yes there would be some advantages, but really, good luck with that.
- pornel 8mo agoToo bad there are 11 players on the pitch, otherwise US could switch entirely to the football fields measurement system.
- kalleboo 8mo agoThe right time to fix that mistake wasn't in metric, it was while creating our numbering system.
- atoav 8mo agoConsider marking it with /s next time.
- tom_ 8mo agoThis can make sense for currency, but units of weight and distance and so on are infinitely divisible. You can just have a third of a metre if you like. Or 333 mm if the inaccuracy is acceptable. And so on.
- wongarsu 8mo agoAnd it's not like 1 is some special value. If you start from a base of 120cm you get enough even divisions that you rarely run into the need for fractions
- fainpul 8mo agoObviously base 60 is superior to all https://www.youtube.com/watch?v=R9m2jck1f90 https://www.youtube.com/watch?v=R9m2jck1f90
- nayuki 8mo agoPossibly yes. But every implementation of base-60 I've ever seen is actually implemented as alternating base-6 and base-10. A true base-60 would have 60 unique symbols for the different digital values, much like how in our set of ten digits {0123456789}, none of the symbols have any rhyme or pattern with respect to the others. Good luck memorizing the ~1800 entries of the base-60 multiplication table.
- unglaublich 8mo agoLol sure, in no A0 years!
- duskdozer 8mo agoBase 12? That's a small number. Now base 13? 13's a big number. The biggest number, perhaps. That's what they're saying at least. Base 13, 13 colonies, now that's America.
- thomasmg 8mo agoThe PDF standard uses base 85 encoding (Ascii 85).
- kstenerud 8mo agoThe metric system is the tool of the devil! My car gets 40 rods to the hogshead and that's the way I likes it!
- bluGill 8mo agoSomeone else must be paying for your fuel. Nobody who pays for their own fuel likes that.
- vidarh 8mo agoUnless everyone worked in base 12 numbers too, that'd be a mess. Part of the beauty of metric is how often calculations devolve to shifting the decimal point.
- Ekaros 8mo agoAnd nothing really prevents metric system from working in base-12. Ofc base 12 kilometre would be larger than base-10. But it still would work. Base 10 really is used because our number system is base 10. And more so base 1000. Apart from some cultures.
- altern8 8mo agoIsn't base 10 easier because you just add/remove zeros, and also we have 10 fingers to count..?
- bluGill 8mo agoNo, converting units is not a useful exercise. airplanes are measured in mm - even the full length is in mm not decameters or even hecameters (i had to look those prefixes up, spellcheck doesn't even know the word, but I think they are correct)
- iggldiggl 8mo agoVehicle drawings (maybe mechanical engineering in general) might be in millimetres, but a lot of civil engineering works in metres, so when designing some bit of infrastructure to fit certain kinds of vehicles, I do need to convert between the two, and the easier, the better.
- nayuki 8mo agoI hope you're comfortable with changing literally every number in society to base 12. My house cost $42A765_12. My SSN is 399-AA-5866 and phone number is (289) 257-B84A. The distance to the moon is actually 50A693_12 feet. I used the additional symbols A and B as per usual notation, but it's okay if society agrees on some other symbols for the extra two digit values. If you don't make the base of the number system agree with the base used for converting between units, then conversion becomes so much harder. For example, it's not immediately apparent that 204 inches is 17 feet, but it is immediately apparent that 204 cm is 2.04 m. Furthermore, when the base disagrees with conversion factors, you run into issues like variable-length fields - like, "2ft 9in", "2ft 10in" (notice the inches transitions from one digit to two digits).
- jxdxbx 8mo agoYes I am literally a member of the dozenal society
- rob74 8mo ago[flagged]
- c048 8mo agoI've heared Americans, unironically, state that the metric system is less precise than the imperial system. I have no clue what the origin is of this myth, but at this point I wouldn't be surprised if Trump held this belief too.
- vpol 8mo ago> origin is of this myth poor education system
- bluGill 8mo agoDepends on the field - it happens that 1\1000 inch is a good tolerance for many machining operations, while metric doesn't have a convient round number close enough to that range to be useful. That doesn't slow down mathinists though, they know the fraction of mm tolerance they need to use and it is what is marked on their tools.
- c048 8mo agoSo do I understand correctly that it's from a tooling issue? If so, thanks for that insight.
- bluGill 8mo agoMore where the marks on the tool are. The marks are arbitrary, but round inch units happen to line up better with what you normally want than round metric. Note that machining is the only place where we work with 1/1000 - that is a fraction that looks metric.
- bluGill 8mo agoTo give an opposite examples, in metric your speed limits are multiples of 10, in the us multiples of 5. Either works but metric has a better tolerance. deca-kilometers perhour would be even better - but no such prefix exists.
- cjs_ac 8mo ago> U.S. customary (the more accurate name for what’s sometimes the called the British Imperial system) For those wondering why there is this distinction, the British Imperial units were created by the Weights and Measures Act 1824; US customary units follow the Winchester Standard of 1588.
- pjc50 8mo agoAnd in a few places they're different (US measuring "cup" vs UK, US gallon, etc) edit: ref https://www.bbc.co.uk/bitesize/articles/zfnjb7h https://www.bbc.co.uk/bitesize/articles/zfnjb7h
- beardyw 8mo agoUK doesn't use cups in recipes and fuel is dispensed in litres. Road signs are still in miles.
- ljf 8mo agoIt has been a long time since fuel was sold here in the UK in gallons, but most cars still are spoken of in terms of MPG (miles driven per gallon of fuel). There are steps to move this to L per 100km - but most people here still use MPG. We also use Pints in pubs, which are a different size to US pints.
- cupofjoakim 8mo agoThe US being stuck in imperial is such a meme nowadays with "freedum units" and the like. It's yet another odd thing that makes it easy for the rest of the world to laugh at the US. In these isolationist times I doubt this will change soon though, but it'd definitely help international collaboration.
- yurishimo 8mo agoEveryone who wants to collaborate internationally is already doing it. Science in the US is entirely metric. Construction and domestic measurements are the two biggest holdouts and honestly they’re both negligible. Given the proliferation of global manufacturing, most businesses are converting at the end before retail for US customers. If the government was competent, they could rip off the bandaid and everyone would adapt within a year or two, but we need to wait at least 3 years for that to even begin to become a possibility again.
- mgoetzke 8mo agoThe fact that canadian lumber companies seem to be switching their machinery to metric is funny though. https://woodcentral.com.au/canadas-sawmills-weigh-metric-switch-to-reach-global-markets/ https://woodcentral.com.au/canadas-sawmills-weigh-metric-swi...
- neutronicus 8mo agoConstruction is negligible? I guess you imagine we’ll all be calling half inch pipe twelve seven after this year adjustment period? I guess people do it with bullet calibers.
- ecommerceguy 8mo agoAren't imperial units considerably easier to calculate on the fly in construction and when squaring? They seem to come more natural for me.
- NuclearPM 8mo agoNo. They are only more natural to you because you are used to it.
- ecommerceguy 8mo agoHave you never used a tape measure before? How about a speed square? Yes easy comes natural for me. I like that.
- pineappleoreos 8mo agoWhen one of familiar with something, it always feels more natural.
- Ronsenshi 8mo agoCan you give an example? I can't imagine calculating conversions between inches and feet to be easier than using millimeters/centimeters/meters. Or using mostly millimeters in construction in Europe. You have one unit to deal with that generally tends to be integer value. No need to fractions.
- bluGill 8mo agoYou don't convert. Airplanes are designed in mm and you never need meters. Houses are in inches - we say 92 5/8. Or sometimes 2 feet 3 inches. Our measurement tools have both marks so we can do it without coversion.
- iggldiggl 8mo agoAirplanes might be designed in mm, but airports are most likely designed in metres, and whoops, suddenly you need to convert between the two. Actually civil engineering as a whole is probably a relatively mixed bunch – vehicles drawings (when you need to design the infrastructure to fit specific vehicles for example) and other small-scale details might be dimensioned in mm, the standard curbstone naming system in Germany is based on centimetres, while infrastructure design itself (definitely including the CAD drawings) usually works in metres.
- NuclearPM 8mo ago[flagged]
- rf15 8mo agoah, if only the french would've lead with that, we would be all on the same page by now
- sarchertech 8mo agoThe problem is that Fahrenheit is a bit more convenient for describing the weather. Inches and feet are a bit more convenient for measuring human scale things and for being easily divisible by more numbers. And we’re used to the rest of it. Unless someone comes along and forces it on you, for the average person, there’s not enough incentive to switch.
- plaguna 8mo ago"Fahrenheit is a bit more convenient for describing the weather" - you might need to show us an example here that is not biased. Because to me, Celsius is a bit more convenient for describing the weather.
- bluGill 8mo agoIt is what you are used to for both of you. you could make your own measurement system and it would work fine once you get used to it - until you need to communicate with someone else who isn't used to it.
- ghaff 8mo agoA big part of it is certainly what you're used to. The other part, which I'm sympathetic to, is that for human scale everyday things, Fahrenheit 0 degrees lines up with really darned cold, 100 degrees with really hot outside of an oven, and the degree size is about twice as granular as Celsius. And while Celsius degree size is indeed widely used in engineering calculations, you're often using Kelvin as the absolute temperature scale. (Which does use Celsius degree increments of course.)
- bryanlarsen 8mo ago> and the degree size is about twice as granular as Celsius. And then they'll argue that the inch is more convenient than the centimeter because it's twice as large. That's backwards. Fractions of an inch are in far more common usage than fractions of a centigrade. Ideal might be both a smaller inch and a smaller centigrade, but between the two a smaller inch is more helpful than a smaller centigrade.
- prmoustache 8mo agofunny related video from Loic Suberville. https://www.youtube.com/shorts/XiEM57ifX54 https://www.youtube.com/shorts/XiEM57ifX54
- altern8 8mo agoWhy change? Imperial was Washington's dream, after all... https://www.youtube.com/watch?v=JYqfVE-fykk https://www.youtube.com/watch?v=JYqfVE-fykk
- alkonaut 8mo agoHaving converted science, manufacturing etc, what's the first (or next) true consumer facing thing that could change?
- mschild 8mo agoGrocery sizes. In fact, a lot of them already have it on the items. Typically because a lot of products are also sold in Canada so they put the ml measurement next to the gallons.
- alkonaut 8mo agoYeah is fl.oz on consumer containers _really_ seen as a volume measurement, i.e. thought of in terms of conversion "How many of these to a gallon", "what does a 6-pack weigh" and so on? Or are they more like t-shirt sizes "I know I want a 16oz can to drink and I know how big they are"?
- amanaplanacanal 8mo agoWhen I go to buy liquor it seems to already be mostly in metric, sizes are 500ml, 750ml, and liter.
- AngryData 8mo agoMost all of it is, even from US companies, but customers still often use the imperial shorthands of pints, quarts, fifths, half gallon, and gallon. Everyone I know just doesn't care that it isn't precisely correct, its all relative due to varying alcohol content anyways.
- nayuki 8mo agoIf I understand correctly, the FPLA ( https://en.wikipedia.org/wiki/Fair_Packaging_and_Labeling_Act https://en.wikipedia.org/wiki/Fair_Packaging_and_Labeling_Ac... ) requires grocery items to be labeled in both American units and metric units. Metric-only is illegal in America but legal and common in Canada. I have shopped in American and Canadian supermarkets and speak from personal observations. It seems the exception is that wine imported into the US can keep metric-only labeling, so I have indeed seen bottles labeled only "750 mL", sold in the US.
- threemux 8mo agoI'd part with cups and teaspoons/tablespoons and the like, but you'll pry inches/feet/yards and fahrenheit from my cold, dead hands. They're both more convenient for daily use. I think I'd prefer to keep miles as well but I don't have a good reason for that one. Fahrenheit has more precision without using decimals for the thing 99% of people are using temperature measurements for: air temp. Where I live, we generally experience 5 degrees F - 100 degrees F at different points of the year. That's 95 degrees of precision with no decimal. In C, that's -15 to 37.8, a mere 52.8 degrees. The difference between 75 (usually a beautiful day) and 85 (hot) is 23.8C to 29.4C. Everything packed into this tight range. Inches/feet being base 12 divides better into thirds and fourths, which is very useful in construction. For science, sure, I'll use metric.
- Tor3 8mo agoWhat's the problem with decimals? They're all numbers. -4.5 degrees C is fine, isn't it? (The actual temperature right here right now). Where's the problem?
- gonzalohm 8mo agoYou don't even need decimals. 45x10^-1. There, fixed
- sfn42 8mo agoYou don't even need decimals. Nobody who uses celsius gives a shit about the decimals. It's -4 or it's -5 and even that distinction is irrelevant. Unless you're doing some kind of scientific calculaton there's no need to think about decimals of celsius at all. Just like Fahrenheit users surely don't care whether it's 50 or 53 or whatever. It's around 50, that's all you need to know.
- Ekaros 8mo agoOnly place I could imagine something is cooking and even there I probably would not be able to differentiate steak at 56C, 57C and 58C...
- hk1337 8mo agoSeems like the U.S. uses metric for most of the important areas and just lets everyone continue to use imperial, whatever they want everywhere else.
- JKCalhoun 8mo ago"Back when I was a Catholic-school kid in northern Wisconsin, my school lessons briefly focused on the metric system. This was in the late 1970s." Man, the progressive school (Comanche Elementary in Overland Park, Kansas!) must have had a huge impact on my life. In addition to open classrooms (I was in Unit 5, not 4th Grade), team teaching, a focus on experimental science, a circular layout to the school with a sunken (architecturally) library in the center… Yeah, we went over the Metric System that whole year. I can still sing the "Metric Family" song from the film on metric units ("Kilo", "Milli", etc.). And to my young and impressionable mind, the U.S. was joining the rest of the "Free World" in a kind of Star-Trek-like casting aside of the old things that divided us—joining each other with a focus on progress, science, space… President Carter came along around the same time or shortly after. And I have a photo of a family road trip to South Dakota, Montana: the sign that indicates the altitude of a particular mountain pass has both feet and meters. I Google-mapped the same location recently and of course it's no longer in meters. I feel like in my elementary school days (the 1970's) the U.S. was on the cusp of a future of optimism—no doubt buoyed by having put astronauts on the Moon, but I was wildly on board for it. But then some kind of shit seemingly started to poison the country. I don't feel we have ever returned to that level of national optimism. Perhaps 1976, the Bicentennial, was the end of it. (Recently watching the film "Nashville" brought me back a bit of the vibe of the times.) I've been missing it my entire life since.
- ericmay 8mo ago> Yeah, we went over the Metric System that whole year. I can still sing the "Metric Family" song from the film on metric units ("Kilo", "Milli", etc.). And to my young an impressionable mind, the U.S. was joining the rest of the world "Free World" in a kind of Star-Trek-like casting aside of the old things that divided us—joining each other with a focus on progress, science, space… I’ve always found this peculiar because at times I have felt the same, but reflecting over the years and I guess as my mind settling on lived experience and opinions I’ve come to appreciate the Imperial system far more precisely because of its absurdities but also because of its history and usefulness without instrument. As someone who, well, finds say Renaissance or Impressionist art to so far be the peak of human artistry, I find the imperial system fits in better with that warmth of humanity in contrast to Frank Lloyd Wright, Banksy, minimalism, and the cold calculation of the more “scientific” metric system. Underneath that all is also this view that the United States at least needs to “join the world” and adopt Metric, and soccer, and such and I find myself increasingly rejecting both and other similar notions in favor of cultural uniqueness and fun over conformity. I hope we never change sustems, and I don’t think we will anytime soon. If we do, however, we should not switch to Celsius because the useful scale of Fahrenheit is far superior 0-100 versus 0-32. Celsius isn’t very Metric-y.
- Kim_Bruning 8mo agoAn argument can be made that we should blame Pirates of the Carribean for the fact that the USA is not metric. O:-) https://www.nist.gov/blogs/taking-measure/pirates-caribbean-metric-edition https://www.nist.gov/blogs/taking-measure/pirates-caribbean-...
- bryanrasmussen 8mo agoI read once that all the educational materials produced to help people move from the old system to metric would cover 3 football fields and weigh more than 28 elephants, so it's nice to see it starting to have some effect.
- baggy_trough 8mo agoHopefully some future president will mandate that the federal government use metric, like Trump getting rid of the penny. The rest of society will gradually come along.
- IAmBroom 8mo agoCarter literally did this. Society did not come along.
- baggy_trough 8mo agoThe feds gave up too early.
- yareally 8mo agoHonestly, the best way to cook is with grams. Throw everything into the same pot on a scale and keep zeroing it out. Way less mess to clean up. All the top baking recipes tend to already be in grams, but there's plenty of others out there that are not Also a great use for LLMs. I'll tell it to convert recipes from volume to grams by estimating density. It's surprisingly accurate
- walthamstow 8mo agoYou can keep your fahrenheit, your feet and your gallons, for all I care, but one thing I will never abide is bolts and nuts and drill bits coming in fractions of an inch.
- consp 8mo agoEverybody still loses the 10mm socket anyway, even in the US.
- frankus 8mo agoThere's now a product for that: https://www.lowes.com/pd/Kobalt-1-4-in-to-1-2-in-Drive-Metric-10Mm-Shallow-Deep-Socket-Set-10-Pieces/5015765789 https://www.lowes.com/pd/Kobalt-1-4-in-to-1-2-in-Drive-Metri...
- zokier 8mo agoFractions of inch are still tolerable. But just having "#X" drills and screws is pretty silly. 7/32" might need some mental arithmetic, but #6 is just unknowable.
- vondur 8mo agoIt’s a bit odd in the U.S. because we use a mix of units, largely due to industries that combine metric and imperial systems. Most people are familiar with metric volume since so many drinks are sold in 1 and 2 liter bottles, and medications are typically measured in milligrams. Lengths and weights are more of a mixed bag. Many track and field events use metric units now, though longer distances are still measured in miles. Temperatures are still Fahrenheit, which I tend to prefer because the smaller increments give a more nuanced sense of change. I’m comfortable with the metric system since I was a chemistry major in college and a mountain biker, where measurements like suspension travel are usually given in millimeters.
- webnrrd2k 8mo agoSpeaking of mixed units, don't forget the alwys fun distinction of avoirdupois pound vs troy pound... People sometimes ask "what's heavier, a pound of feathers or a pound of gold?", the implication is that you're stupid for for asking a dumb question. The technically correct answer is that the pound of feathers is heavier. The expected answer is usually that they're the same weight, because there is no difference in weight between the two things that both weigh a pound. The problem is that, in the USA, a pound of feathers is measured with the avoirdupois pound, while a pound of gold is measured in troy pounds. The troy pound is lighter than the avoirdupois pound, so the answer is that a pound of feathers is heavier. While a troy ounce is heavier than the avoirdupois ounce, and the grain unit is equal in both. So, depending on whether you ask for a pound/ounce/grain, the answer can change. https://en.wikipedia.org/wiki/Troy_weight https://en.wikipedia.org/wiki/Troy_weight
- samus 8mo agoThe smaller increments of Fahrenheit don't matter outside of a chemistry lab.
- pengaru 8mo agoIt will never cease to drive me batty every time I try find a metric fastener for an automotive purpose at a local hardware store. There are many reasons I can find for leaving the US, but engaging in DIY projects utilizing local suppliers are what's come closest to pushing me over the edge. Especially in this post-SEARS hellscape of low quality made in china junk the market's flooded with. Now not only can I never find the fasteners I need, the tools suck too!
- qingcharles 8mo agoI used to end up blowing all my money on ordering from Amazon and paying for same-day delivery, which usually means within a couple of hours in big cities. I'd always waste my time going to Home Depot etc and getting aggravated at their metric fastener selections.
- farceSpherule 8mo ago[dead]
- alnwlsn 8mo ago>They specify dimensions in feet, inches, and fractions of an inch. But not all of them do. There are many more fun and exciting non-metric measurements you might encounter than plain old fractional inches. A fabricator might encounter sheet metal thickness in "gauge". Wire sizes, ammunition, and machine screws also come in "gauge" sizes but all four are different scales. US drills come not only in fractional inch sizes, but letters and numbers as well. Furnace efficiency is often specified in percent, but air conditioner efficiency comes in SEER. Water softener capacity is in "grains". Pipe threads come in "inch sizes", but that usually means NPT. Metal hardness and rubber durometer measurements have their own scale which doesn't really belong to either camp. To be fair, a lot of these are categorical units. Screws come in #2 or #6 or #4, but you'll never need to worry about #3.7. A wise professor once told me "All these different units will not be going away within your lifetime, so you better get used to working with them."
- zahlman 8mo agoGauges are a measurement, but they aren't a unit. They don't necessarily have any linear correspondence to actual distance/volume/whatever, and in fact are typically inverse (higher number = smaller thing). And yes, they're categorical. (Sometimes you even see 00 as a gauge number.)
- zokier 8mo ago> Sometimes you even see 00 as a gauge number or 0000. Which then can conveniently be abbreviated to 4/0.
- vablings 8mo agoMetal hardness having a bunch of different units is quite annoying but also interesting. There are quite a few ways to measure the hardness the most interesting being Vickers. You plunge a diamond of a known force into a surface and measure the size of the indentation. This is surprisingly accurate but does leave a small diamond mark on your surface. With a sufficiently small part a blacksmith or other folks can determine the hardness of a steel just by listening to how it rings. Hey, you can also test for cracks with a ring test, the most common use is ring-testing a vitrified grinding wheel to see if there is no crack Alot of engineering is just listen and maybe the odd hit with a hammer
- gossamer 8mo agoThe highway between Tucson and Nogales, Arizona, I-19, is the only highway in the country that has signage only in kilometers. It has been that way since 1980. It was a pilot project for the Metric Conversion Act. The highway is 102 kilometers long (63 miles).
- buildsjets 8mo agoIf you specify all your bolt heads as 19mm and 13mm, then a 3/4" wrench or a 1/2" wrench is usually good enough to get the job done. Similarly, a 1/4-20 bolt will fit in a M6 tapped hole if you use a large enough hammer. A hazardous aspect of US threadforms is that #10-32 machine screws and #8-32 machine screws have the same pitch. So you can fit #8 bolts in a #10 hole and sometimes, they FEEL like they made good torque, because they engaged one side of the tapped hole, when they really have no tension capability whatsoever. Reference the British Airways flight 5390 accident where the pilot got sucked 3/4 the way out the cockpit window and slammed against the side of the fuselage while a flight attendant clung to his feet and the co-pilot safely landed. Also note that a British designed and built product was using US threadforms... https://admiralcloudberg.medium.com/the-near-crash-of-british-airways-flight-5390-89a4370c92bb https://admiralcloudberg.medium.com/the-near-crash-of-britis... https://en.wikipedia.org/wiki/British_Airways_Flight_5390 https://en.wikipedia.org/wiki/British_Airways_Flight_5390
- tzs 8mo ago> Reference the British Airways flight 5390 accident where the pilot got sucked 3/4 the way out the cockpit window and slammed against the side of the fuselage while a flight attendant clung to his feet and the co-pilot safely landed. That incident led to a major change in how aircraft windows were designed. Instead of being fitted from the outside they were changed to being fitted from the inside. When fitted from the outside the job of the fasteners is to keep the cabin pressure from blowing the window out when the plane is high up and the outside pressure is low. When the plane is on the ground gravity will keep the window in place and the fastener isn't doing much. Botch installing the fasteners and you don't find out about until the window blows out at high altitude, like on that flight. When fitted from the inside the job of the fasteners is to keep the window from falling in due to gravity when the plane is on the ground or at low altitude. At higher altitudes the cabin pressure pushes the window firmly into the frame and the fasteners aren't doing much. Botch installing the fasteners and the window falls in on the ground or at low altitude which is a lot easier to deal with then a window blowing out at high altitude.
- frankus 8mo agoThe diabolical case is M5 versus 10-32. About a 4% difference in diameter and about 0.8% difference in thread pitch. Basically indistinguishable with the naked eye and even the "nest the threads in each other" check doesn't help without a pretty long length of threads.
- beloch 8mo agoTo those who cling to customary units because... 1. "They're more intuitive". They're not. You're just familiar with what 70 F feels like. If you're used to metric, 70 F is meaningless, but you intuitively know what 20 C feels like. 2. "Metric leads to lots of awkward numbers." All systems will fortuitously have round numbers in some contexts and awkward numbers in others. Customary units are different in that there are awkward numbers baked into the system. e.g. 5280 feet in a mile. 128 ounces in a gallon. 3. "It's too much trouble to change." You're already using metric units. U.S. customary units have, metrologically, been defined in terms of metric units since the Mendenhall order of 1893[1]. i.e. A meter is defined in terms of how far light can travel in a period of time defined by a hyperfine transition frequency of Caesium. If you needed to know exactly how long a meter is for a very precise measurement, a reference meter could be produced in a lab by aliens who have no idea what a meter is by using this definition. No such definition exists for a foot or yard. Nobody maintains physical reference yards (the old-school method) anymore. If you want those aliens to measure out a yard precisely, you tell them how to measure out a meter and then tell them 1 yard = 0.9144 m. [1]https://en.wikipedia.org/wiki/Mendenhall_Order https://en.wikipedia.org/wiki/Mendenhall_Order
- prmph 8mo agoYeah, those people should also think about the fact that even the customary units die-hard do not use micro-feet, milli-feet, or nano-feet, etc.
- fragmede 8mo agoA slightly more esoteric Imperial unit is "mils", for thousandths of an inch. 1 mil = 0.001 inch. Which means 1 mil = 25.4 micrometers if we also want to use a non-traditional meter measurement.
- bigstrat2003 8mo ago> You're already using metric units. No we aren't. It doesn't matter what the units are defined as, that is not what determines which units we are using.
- bigstrat2003 8mo agoPeople get bogged down in arguments about what's better or more natural, but in my opinion those always miss the point. The truth is, there's no incentive for the US to switch. If you're a typical adult living in the US, you already know all the conversions you will need (12 inches to a foot, etc etc). The math isn't hard, because you always have a calculator at hand in this age. In short, imperial units have zero downside for most people. On the other hand, switching units of measurement does have a major downside as you have to relearn to estimate everything in the new units. That would be fine if metric was solving a problem for you... but it's not, so why switch? The only people who benefit from a switch to metric are kids (cause they won't have to learn the imperial conversions). And they, for better or for worse, don't get a say. If people really want the US to switch measurements so badly (which I have no idea why anyone gives a shit what our country does, it's not like it affects them), then they need to come up with an actual compelling benefit to adults in the US if they switch. 100 years ago there was one: you can do conversions more easily. But today there is not, and until one surfaces there's going to be zero pressure to switch units.
- upofadown 8mo ago>“I’m currently working on a mounting plate that’s 4.5 by 8 in. that needs a 40 mm bore 1/2 -in. deep located 75 mm from the edge with m10 tapped holes and two 1/4-20 set screws tangential to the bore. Please kill me.” When I was designing stuff here in Canada, that was basically Wednesday. One big advantage of the USA withdrawing from trade is that Canada will have the opportunity to finally complete the metric conversion.
- dekhn 8mo agoI work across both english and metric all the time (CAD, 3d printing, science, woodworking in the US) - I just mentally switched (age 52) to metric first in my head (specifically, I think "that's 10cm" not "that's 4 inches" when I look at something. Woodworking became a lot more enjoyable- I don't know why- when I started to think "I need to shave off 1mm" instead of "shave off 3/64 inch" or whatever.
- watersb 8mo agoMy elementary school years in the US really pushed metric units. And every science class I've ever had was exclusively SI units. Except for Thermodynamics, which sometimes uses BTUs and steam engines.
- estimator7292 8mo agoWe're in such a stupid time. I'm an EE, I typically do all my engineering in millimeters, but most of my coworkers prefer the clownshoes unit "mils". Half our soldering irons are set to Fahrenheit, the others Celsius. In ordinary every day life, I've found that I use metric for measurements under an inch or under an ounce. At a certain upper limit it makes more sense to use metric for large values too. So I have to suffer with the magic constant 25.4 bouncing around my brain every day forever and constantly converting trivial measurements into worse units. I will never convert a measurement to fractional inches. If you must have inches as an input you can suffer a damn decimal point.
- jrm4 8mo agoObligatory "what it's based on doesn't matter." Like programming languages and UIs, it's what and how people use them. Imperial tends to be better because it's more "evolutionary."
- johnea 8mo agoThis just reinforces my old saying: If you want to try to understand why the US is so fucked up, just look at England...
- Ylpertnodi 8mo ago> just look at England. And perhaps Scotland, Wales, and Northern Ireland, and/ or Great Britain, the British Isles, and/ or the United Kingdom? Fucked up, indeed.
- jiggawatts 8mo agoThe fish is the last to know it lives in water. 96% of the world’s population and 75% of its nominal (but not PPP adjusted!) GDP is metric. All science is metric. Other arguments simply don’t matter. How fine the Fahrenheit vs Celsius scales are or whatever is pointless, irrelevant debate. Join the rest of us, or slowly fade into irrelevance. There is no third option. You’re that one mansion with the doddering old cranky fool still lighting their place with town gas while everyone else has been using electric lighting for decades. The next time the street is dug up, your pipes won’t be reconnected. “So what if our spaceships occasionally crash into Mars at full speed because we got mixed up with our units… again? We can afford it!” — apologists.
- insane_dreamer 8mo agoI don't think the title is accurate. There is no super-slow "conversion" of the US to metric. There is a super-slow adoption of metric _alongside_ the "customary" Imperial system.
- dragonwriter 8mo agoThe US Customary system is not the Imperial system. Though they are frequently confused, since they share a bunch of units, and even more names of units with different definitions.
- insane_dreamer 8mo agotrue, but they're both equally outdated for the purposes of this discussion
- mark-r 8mo agoWe may get there eventually just as a consequence of being part of the world economy. I noticed a couple of years back that my "U.S. Customary" wrenches weren't fitting my new plumbing fittings which were definitely not metric, but metric wrenches did. Probably made in China. Then last summer I noticed something similar with lag bolts. The U.S. Customary socket fit the head, but it was nearly identical to a metric one that fit just a little better. The threads are designed to go into wood, not a nut, so if they were metric you'd never even know.
- pfannkuchen 8mo agoWith most calculation happening via computer these days anyway, do the advantages of the metric system become less relevant?
- yegle 8mo agoIt becomes my habit pointing out the Metric sign on EB 580 when driving my out-of-town friends to the Premium Outlet. https://www.sfgate.com/travel/article/how-kilometers-appeared-on-bay-area-highway-sign-18601009.php https://www.sfgate.com/travel/article/how-kilometers-appeare...
- rstuart4133 8mo agoI actively avoid stuff made in the USA, precisely because they don't use metric. For example, you can get a USA bolt with all sorts of threads and dimensions, or you can buy a 100mm M8 that is compatible with every other M8 bolt / nut made in the world. That boils down to bolts made in any country, bar the USA. Every time the USA manufacturers something that isn't metric, you've made it incompatible with the rest of the world. The USA got away with that when I was young because they were the world manufacturing powerhouse. Now, those powerhouses are based on Asia. They define the units most of the world sees, and they use metric. So if I buy a Chinese mower, all the bolts are metric and I'm guaranteed the local hardware store stocks them. Time has moved on, the USA is now a follower, not a leader in most things bar digital services. If they want to return to selling those things to the world the speeds have to be in km/hr, weights in kg, sizes in mm or meters, the temperature in Celcius, pressures in Pascal's.
- tsoukase 8mo agoUS system was good for the expansion in Far West 200 years ago. Count steps and thumbs to measure distance and feel the temperature on your skin. Now it has no utility and the US should "surrender" in a democratic fashion to the rest of the world. Of course any definition of a physical constant is valid, like how long I run with one breath right now. But there is already a majority that wins.
- yencabulator 8mo agoPure hell of growing up metric and being forced to use inches is - what's half of 1-7/8" Metric: half of 44mm is 22mm. half of 45mm is 23mm [1]. half of 46mm is 23mm. Trivial - which one is bigger 5/16" or 3/8" Metric: 9mm is obviously bigger than 8mm. Fractions are just unnecessarily complicated. [1] Millimeters are small enough that you'll never need to go below that except in specialties like machining.