Inches or mm - Page 1
Forum section: electronics / general

author: ProBang2
author_rank: Frequent Contributor
timestamp: August 26, 2016, 01:02:18 am
content: If I remember correct:An old thread about metric vs. imperial system already exists anywhere in this forum.

author: Ian.M
author_rank: Super Contributor
timestamp: August 26, 2016, 01:06:57 am
content: I don't care whether its dimensioned in inches, mm or attoparsecs as long as the units are clearly identified.

author: madires
author_rank: Super Contributor
timestamp: August 26, 2016, 01:11:09 am
content: Megameters?

author: Richard Crowley
author_rank: Super Contributor
timestamp: August 26, 2016, 01:12:00 am
content: How long is a string?How old is a duck?When does the river come by this way?You get more mm for your inch.

author: rs20
author_rank: Super Contributor
timestamp: August 26, 2016, 01:18:35 am
content: I'm staunchly metric 99% of the time, but I do have a guilty soft spot for thou in electronics. The pitch of DIP components being 100 thou is so much cleaner than 2.54mm, and using thou-based grids in PCB design often works out much more nicely.

author: Muttley Snickers
author_rank: Unknown
timestamp: August 26, 2016, 01:21:39 am
content: I'm still trying to fathom out the question, it might be too deep for me to comprehend.

author: ANTALIFE
author_rank: Frequent Contributor
timestamp: August 26, 2016, 01:23:48 am
content: Let the flame-wars begin

author: ebclr
author_rank: Super Contributor
timestamp: August 26, 2016, 01:26:28 am
content: I guess all USA people will vote for inch, everybody else mm

author: IanB
author_rank: Super Contributor
timestamp: August 26, 2016, 01:54:31 am
content: cm are feeling left out

author: zapta
author_rank: Super Contributor
timestamp: August 26, 2016, 02:09:44 am
content: I tried once to use millimeters but the guy at Home Depot didn't understand what a 50.8 by 101.6 is.

author: Halcyon
author_rank: Unknown
timestamp: August 26, 2016, 02:11:02 am
content: Isn't interesting that people always measure 'appendages' in inches, even in countries using the metric system?

author: Mr.B
author_rank: Unknown
timestamp: August 26, 2016, 02:27:49 am
content: Quote from: zapta on August 26, 2016, 02:09:44 amEven in a country using the metric system like NZ, the 'Home Depot' guy still wouldn't understand that.They do of course know exactly what you want when you ask for asix foot stick of two by four.

author: sleemanj
author_rank: Super Contributor
timestamp: August 26, 2016, 02:35:59 am
content: Quote from: zapta on August 26, 2016, 02:09:44 amFun fact, a 2x4 is not 2x4, the 2x4 is the unmilled dimension, after milling (what you buy) it has lost about 1/2 an inch on each dimension. Your home depot guy would probably be just as confused if you asked for a 3.5x1.5 :-)Conversely, at least here in NZ, if you waltz down to your local Mitre 10 or Bunnings and ask for a 2x4, you'll surely be helpfully directed to the 50x100 timber, which doesn't measure 2x4, or 50x100 (but is none-the-less what you wanted).

author: Monkeh
author_rank: Super Contributor
timestamp: August 26, 2016, 03:01:35 am
content: Quote from: sleemanj on August 26, 2016, 02:35:59 amPlaned. Can't say I've ever seen timber get milled.Rough sawn will be very close to advertised dimensions. Planed around 5-6mm less.

author: ajb
author_rank: Super Contributor
timestamp: August 26, 2016, 03:36:51 am
content: Being 'murican, I think in feet and inches by default, but I'm comfortable with either system. The annoying part is being stuck dealing with both all the time. We use some component assemblies that use metric hardware, and other components that use inch hardware, so we ridiculously have to stock both systems of fasteners, and often wind up with both in one product. I try to stick with metric hardware when I can, but specialty nuts-and-bolts type stuff is at best much more expensive and at worst unobtainable* in metric sizes in the US. Raw materials are, of course, also sold in inches, but that's easier to work around. Who cares if Solidworks says the part is .063" or 1.6mm thick, as long as the CAM** is done with the right units, the part will come out right. For PCBs, Altium has a single-key shortcut to switch between mm and mils, which is handy, but I've occasionally had weird problems with DRC and interactive routing that I suspect are due to rounding errors when using metric grids and imperial trace/space rules.* in small quantities and reasonable lead times, anyway.** could be Computer Aided Machining or Calipers And My eyeball, it's true either way.

author: Monkeh
author_rank: Super Contributor
timestamp: August 26, 2016, 03:39:20 am
content: Yeah, availability of metric hardware in the US is appallingly bad, along with sundry accessories (finding nylon washers proved an odd challenge last year, even in imperial sizes - I ended up flying out with a bag of them).Mind you, imperial hardware isn't terribly different here. Trying to find sane prices on 4-40 hardware (despite being hugely common!) can be tricky, other sizes far harder. Thankfully a lot less of a problem, as with some exceptions (computers being one of them), 99% of equipment is metric these days.

author: calexanian
author_rank: Super Contributor
timestamp: August 26, 2016, 03:51:52 am
content: I prefer leagues and fathoms. Occasionally I will throw in a cubit. When speaking about living being height I will typically use hands, and for weight I use stone primarily. O0

author: mtdoc
author_rank: Super Contributor
timestamp: August 26, 2016, 04:34:45 am
content: Quote from: Monkeh on August 26, 2016, 03:01:35 amHa! Here in the US, logs are milled into dimensional lumber. This is done at a sawmill.Individuals may use planers sometimes to reduce the thickness of dimensional lumber or provide a smoother surface for finish carpentry or cabinetry.As far as mm or inches. I use metric for my day job but at home and work with wood or do other building projects in inches.

author: Monkeh
author_rank: Super Contributor
timestamp: August 26, 2016, 04:42:21 am
content: Quote from: mtdoc on August 26, 2016, 04:34:45 am'dimensional' would be 'sawn'. ie. cut with a saw. The mill is the building or plant.QuoteYou can buy it planed, either square or radiused. That's where the dimensional discrepency comes in, 4x2 PSE is planed out of.. 4x2 sawn. At least with modern sizes over here (47x100mm). The US apparently is, like with most things, different.

author: mtdoc
author_rank: Super Contributor
timestamp: August 26, 2016, 04:54:18 am
content: Quote from: Monkeh on August 26, 2016, 04:42:21 amTechnically in the US, I believe dimensional lumber is planed and radiused at the mill, though you can buy square "rough cut" lumber - especially common when exceeding the standard sizes.I believe the standard dimensional lumber sizes originated from what the "green" wood was cut to , then after drying it came down to the smaller size. But I think now it is all computerized milling to give the standard actual sizes after drying which are obviously smaller than the nominal.

author: ProBang2
author_rank: Frequent Contributor
timestamp: August 26, 2016, 06:27:31 am
content: If my memory does not work completely wrong then was in the late 70´s (?) a big campaign in the USA for the change to the metric system. What happend?

author: ivaylo
author_rank: Frequent Contributor
timestamp: August 26, 2016, 07:48:30 am
content: Quote from: ProBang2 on August 26, 2016, 06:27:31 amNothing, looks like they reached half way then halted. I had a Camaro '84 (piece a junk automobile) with engine in metric and body in imperial so you needed two sets of all tools to work on it. Nightmare...I grew up metric, moved here, took me 15 years to be able to switch back and forth. Now can tell you if a bolt is metric or imperial by just looking at the thread (esp. the small sizes), pretty useless skill, but there...

author: Miyuki
author_rank: Frequent Contributor
timestamp: August 26, 2016, 08:13:07 am
content: Interesting thing is that even at continental Europe where everything is metric is steel pipes in inches

author: tautech
author_rank: Super Contributor
timestamp: August 26, 2016, 08:57:49 am
content: Quote from: Miyuki on August 26, 2016, 08:13:07 amYep, but galv pipe (guess that's what you mean) is measured innominalinternal diameter and approximate at that. For example take an 1" bar and it easily fits within 1" galv water pipe.But still the purist metric police would have us call it 25mm pipe.

author: helius
author_rank: Super Contributor
timestamp: August 26, 2016, 09:04:35 am
content: Keeping 25.4 mm/in memorized is helpful. The traditional American units are simply more convenient for everyday things: the space between each of your fingers is about an inch, for example, which makes them very easy to estimate.The units also provide intuitive "buckets" that can be distinguished without any tools. Each 10 degrees F corresponds to a different kind of weather that is very easy to tell just by the way it feels. 50s - 60s - 70s - 80s - 90s are just like cold - cool - pleasant - warm - hot. This is the reason the Fahrenheit scale was developed, by the way: centigrade already existed, but it didn't correspond to people's ordinary experience of weather.I'd respect metric advocates more if they were consistent and used decimal time.

author: b_force
author_rank: Super Contributor
timestamp: August 26, 2016, 09:47:14 am
content: Might be convenient, until you have to scale up/down.That's were the trouble starts big time.I can think in inch or feet if I need to, but going from one unit to the other is just the most illogical and inconvenient way you can imagine.The whole idea of the metric system is that you can simply scale up and down with decimalsBesides, it's not so difficult to remember and count with 2.5(4) instead of 1.Talking about temperature, why on earth don't we just simply use Kelvin?Scientifically that's the only correct way to use temperature anyway.Quote from: Miyuki on August 26, 2016, 08:13:07 amWell, as far as I know, we had the Dutch 'thumb' (duim)measure. Which is extremely close to the inch.I think Germany also had a similar thing in the past.

author: sleemanj
author_rank: Super Contributor
timestamp: August 26, 2016, 10:04:41 am
content: Quote from: helius on August 26, 2016, 09:04:35 amMaybe if you are 3 years old?!If I spread apart my 1st and 2nd fingers (ie, either V for victory, or up yours depending on rotation), the tips are about 10cm apart. Similarly my little finger and thumb when spread apart are about 20cm, and little finger and 1st finger are about 15cm.Anyway, I'll just leave this herehttps://youtu.be/r7x-RGfd0YkAnd of coursehttps://youtu.be/mHeo62B0d0E

author: Srbel
author_rank: Frequent Contributor
timestamp: August 26, 2016, 10:08:55 am
content: My nob sounds bigger in mm, so I'm sticking with mm.

author: madires
author_rank: Super Contributor
timestamp: August 26, 2016, 10:16:47 am
content: Quote from: helius on August 26, 2016, 09:04:35 amIt's simply what you grown up with. If it was quarks (let's say 1 quark = 3.68mm), you would be happy with that. And you would also find things that match a quark pretty good. The benefit of the metric system is its consistency. It's not 12 inches = 1 foot, it's 10mm = 1cm = 0.1dm (milli = 1/1000, centi = 1/100, deci = 1/10). Or instead of 3 feet = 1 yard, it's 100cm = 1m. The magic lies in the units. The funny thing is that you use pF, kOhms and mA

author: JPortici
author_rank: Super Contributor
timestamp: August 26, 2016, 10:21:05 am
content: Quote from: Ian.M on August 26, 2016, 01:06:57 amQuote from: rs20 on August 26, 2016, 01:18:35 am+1

author: b_force
author_rank: Super Contributor
timestamp: August 26, 2016, 10:25:03 am
content: What really makes my head explode is the 3/8 of an inch or 11/16, 9/16 etc etcAnd instead of staying consistent to name everything the same, no let's 'simplify' things.So you get a weird sum of 3/8 + 9/16 + 1/2 + 1/4, which means you have to bring back the divisor back to 16 again.If everything comes down to 1/16 when summing, why not just freaking ALWAYS call it that way.WHaaaaaaaaaaaaaaaarrghSo weird working with fractions, which is btw, also physically INCORRECT, because it means (by definition!) that your measurement has an infinitesimal small accuracy.Which is according to Heisenbergs principle AND statistics used in determine a unit, impossible!(BTW, sure enough, in datasheets/developing PCBs it's not that much of a problem. But when building stuff and using a ruler or tape measure, it's just soooo confusing)

author: tautech
author_rank: Super Contributor
timestamp: August 26, 2016, 10:27:44 am
content: Quote from: b_force on August 26, 2016, 10:25:03 amOr add them together as thou's or mils.....easy.

author: m98
author_rank: Frequent Contributor
timestamp: August 26, 2016, 10:53:41 am
content: Quote from: helius on August 26, 2016, 09:04:35 amJust measured, I get anything from 2,3 to 5,6 inches between my fingers. On the other hand, the nail of my pinky is exactly one centimeter wide. Not that I'd ever had the desire to estimate a measure like this.Quote from: helius on August 26, 2016, 09:04:35 amI just don't get it, really. This just doesn't make any sense to anyone in the whole world except the americans. You can do exactly the same thing with any temperature scale, when you're used to it. No one used to the metric system has any difficulty estimating the apparent temperature in degrees celsius.Quote from: helius on August 26, 2016, 09:04:35 amJust look at this map. Not respecting the "metric advocates" actually means not respecting 94% of the worlds population.Also please note that minutes, hours, days and years aren't defined in the SI-System, but are still tolerated for use with its units. Because, really, what's the choice? You can't change the time units the whole world uses. And the one who'd start, would be totally lost interacting with anyone not using decimal time. Also it would mean changing the actual duration of a second, which would really mess up a whole lot of other things.EDIT: To make it clear, the map shows all countries who've officially adapted the SI system.

author: b_force
author_rank: Super Contributor
timestamp: August 26, 2016, 11:02:40 am
content: That map is unfortunately not completely accurate (no pun) for standard time notation.A lot of countries still only use the 12 hour notation instead of 24 hour.Well, actually you can better call it time notation with two extra letters needed.I guess also to make notation and implementation more convenientIf we need to use any type of limbs anyway, I think the thickness of the fingers (from top to bottom) is on average 'most convenient'.But ones again, the unit is as accurate as the standard deviation of the average x 3 at least.So with my fingers that will be15±1.4 mm* 15±3mm (with 3 sigma = 99.8%).I guess that says enough.That number is even getting worse if I spread my fingers.* official notation actually needs to be in metersedit:forgot that we need to divide by the square root of the count of measurements to get the standard error.

author: tautech
author_rank: Super Contributor
timestamp: August 26, 2016, 11:06:06 am
content: Quote from: b_force on August 26, 2016, 11:02:40 amI'd bet their military and aviation industries don't.

author: Brumby
author_rank: Unknown
timestamp: August 26, 2016, 11:26:01 am
content: mmIt's far easier to add, subtract, multiply and divide ... and an ordinary calculator can handle it.Also, millimetres are inherently more accurate as an integer quantity - and if I want to make an incremental adjustment, I don't have to go through the demonic denominator dance.

author: b_force
author_rank: Super Contributor
timestamp: August 26, 2016, 11:44:29 am
content: Quote from: Brumby on August 26, 2016, 11:26:01 amI don't understand why people keep saying that, but that doesn't necessarily have to be true.

author: Zero999
author_rank: Super Contributor
timestamp: August 26, 2016, 11:55:32 am
content: For measuring small dimensions, thou is often used rather than inches, 1th = 0.001" = 25.4µmI don't have a problem with inches vs mm and use them both in PCB design but what I don't like is feet, pounds, pints and all of that nonsense, especially when there often is no standard, especially for volume with US pints being different to UK pints.As far as Fahrenheit vs Celsius is concerned: both are just as bad as each other because they both involve negative numbers and neither are Si units. We should have scrapped them both a long time ago and moved to Kelvin or Rankine (both just as good as one another) which eliminates the negative number nonsense.

author: Brumby
author_rank: Unknown
timestamp: August 26, 2016, 12:15:49 pm
content: Quote from: b_force on August 26, 2016, 11:44:29 amSTOP BEING SELECTIVE!!!My statement was:Quote from: Brumby on August 26, 2016, 11:26:01 am

author: ProBang2
author_rank: Frequent Contributor
timestamp: August 26, 2016, 12:17:01 pm
content: Quote from: helius on August 26, 2016, 09:04:35 amNope, nope and... nope.The Fahrenheit scale was developed for a wider span of the scale, defined with reproductable fixpoints.The centigrade scale does not already existed. (°F-scale invented 1724. °C-scale invented 1742. Yes! History exists before 1776...)The Fahrenheit scale is in no way related to weather or the experience of weather.(Quote:"The lower defining point, 0 °F, was established as the temperature of a solution of brine made from equal parts of ice and salt. Further limits were established as the melting point of ice (32 °F) and his best estimate of the average human body temperature (96 °F, about 2.5 °F less than modern measurements).")Full article on wikipedia:http://en.wikipedia.org/wiki/Fahrenheit

author: m98
author_rank: Frequent Contributor
timestamp: August 26, 2016, 12:19:31 pm
content: Quote from: Hero999 on August 26, 2016, 11:55:32 amUhm, wrong. Degrees Celsius is just a derived unit, shifting the base unit Kelvin to a human usable range. This makes it a SI unit, opposed to Fahrenheit, which isn't. Other derived units are for example: Newton, Volt, Ampere, Ohm, Farad, Coulomb, Joule, Watt, Henry, Pascal, Hertz, Siemens, Tesla.So, yeah, only using SI base units would be quite... uncomfortable for all parties involved.Also, just learned about degrees Rankine...

author: Brumby
author_rank: Unknown
timestamp: August 26, 2016, 12:26:26 pm
content: Quote from: Hero999 on August 26, 2016, 11:55:32 amThat is a parallel to the fundamental basis of the metric system - divisions based on powers of 10. With the metric system, that's all you get. However with imperial, you can have 625 thou or 5/8" - and converting between the two formats is not trivial - unless you fall on known values, such as this example.

author: JPortici
author_rank: Super Contributor
timestamp: August 26, 2016, 12:31:46 pm
content: Quote from: m98 on August 26, 2016, 10:53:41 amwe do:"un deo de grappa"a finger of grappa(to be added into a short coffee as a digestive)this actually means to pour a quantity of liquid such that it will be 1 cm tall, regardless of the glass/cup surface area.for wider glasses or containers the finger is taken respective of the bottle

author: Brumby
author_rank: Unknown
timestamp: August 26, 2016, 12:35:10 pm
content: .... there are some things that transcend any formal system of measurement.

author: madires
author_rank: Super Contributor
timestamp: August 26, 2016, 12:40:44 pm
content: Please seehttps://en.wikipedia.org/wiki/Conversion_of_units_of_temperature#Comparison_of_temperature_scalesfor a few degrees more funChoose one scale from Kelvin, Celsius, Fahrenheit, Rankine, Delisle, Newton, Réaumur or Rømer.

author: ajb
author_rank: Super Contributor
timestamp: August 26, 2016, 01:42:34 pm
content: Quote from: Brumby on August 26, 2016, 12:26:26 pmWhat? Converting between fractional notation and decimal notation *is* trivial. 5/8" -> five divided by eight -> 0.625. If you want to go decimal->fractional, multiply the decimal by your desired denominator (precision): 0.625 * 8 = 5 -> 5/8. It may seem silly, but it's not complicated. Anyway, it's not common to have to do that--generally if you're working in fractional inches you stay in fractional inches, and if you're working in decimal you stay in decimal. People who work in fractional inches generally aren't working to better than 1/8" precision, so it's not all that difficult. Furniture makers and such will go to 1/32" or MAYBE 1/64", but again, they're not having to convert anything, since the materials and tools will all be in fractional inches already.People often look at the US and say "Why don't you use metric? It's so much BETTER!", and yeah, we know. That's why the people who do enough of the type of number-crunching where metric makes an appreciable difference are already using it. Everyone else doesn't do enough of that type of math to care, and sticks with what they're most comfortable with or what best suits the physical things available to them (materials and tools, etc).

author: Ian.M
author_rank: Super Contributor
timestamp: August 26, 2016, 02:51:16 pm
content: A 'near enough' conversion for fractional inches that you can easily do in your head is to take 1/256" as 0.1mm That leaves you with 0.2mm error on 1". If you need additional precision and you are converting to metric, subtract 0.1mm at >1/4" and another 0.1mm per extra 1/2" (i.e at 3/4", 1 1/4", 1 3/4" etc.) for a maximum error of 0.05mm (20 thou).

author: IanB
author_rank: Super Contributor
timestamp: August 26, 2016, 03:06:19 pm
content: Quote from: ProBang2 on August 26, 2016, 12:17:01 pmExcept ...QuoteThe story goes that Herr Fahrenheit did not like the idea of negative temperatures, so he tried to establish zero as the coldest temperature seen in winter so that thermometers would never have to go below zero.

author: digsys
author_rank: Unknown
timestamp: August 26, 2016, 03:47:31 pm
content: Quote from: JPortici+230 yrs of PCB layouts is too embedded to change from imperial (decimal ONLY, none of the 1/16, 3/8 mess), but I do now try to chose imperial dims that havea close whole mm conversion. Metric for all CAD work, rarely ever see imperial there. BUT, If I'm out with the boys .. cars, bikes, boats etc it's always imperial."ooo nice twin 6" SUs you picked up" sounds a lot better than "ooo a nice twin 152.4mm SUs you picked up" :-)You definitely need to be fluent in both

author: vodka
author_rank: Frequent Contributor
timestamp: August 26, 2016, 05:08:07 pm
content: Quote from: ajb on August 26, 2016, 01:42:34 pmNeither better nor worse , almost all countries gave up their own measure system for adopting an international standard with the goal to easy the trades with other countries,if not the international trade would be a chaos, but somebody always has to have an ego as the nuts of the General Espartero horse.

author: Augustus
author_rank: Regular Contributor
timestamp: August 26, 2016, 05:12:06 pm
content: 'nuff said...

author: b_force
author_rank: Super Contributor
timestamp: August 26, 2016, 06:29:51 pm
content: I opt for year-month-day, because that sort better with file names.If the imperial system was "so much better" I find it hard to believe that most universities, scientists and other countries would be so naieve.Maybe they are hiding something from us!!!!!

author: IanB
author_rank: Super Contributor
timestamp: August 26, 2016, 06:54:36 pm
content: Quote from: ajb on August 26, 2016, 01:42:34 pmI think people often overlook that the US (and the UK before) havealwaysused decimal measurements for engineering and architecture. There is no stunning advantage to using a different measurement system. For example, length in engineering and machining is measured in inches. So a dimension could be 87.328 inches. Architecture would use feet. So a dimension might be 184.32 feet. A weight expressed in pounds could be 384.3 lb. (Or thousands, or millions, of pounds for large quantities.)Every time, measurements are decimal. It would be foolish to do otherwise.

author: Ian.M
author_rank: Super Contributor
timestamp: August 26, 2016, 07:20:30 pm
content: If you are doing anything more complex than surface area calculations, use MKS S.I. units. If you have to use imperial or US units, convert to SI on entry, and convert back for display, but to prevent accumulated rounding errors, use the SI units result for further calculation, not the converted result.Working in mixed units is a good way to FUBAR your project, as NASA found out back in '99.https://en.wikipedia.org/wiki/Mars_Climate_OrbiterI doubt decimal inches were in common use even in instrument makers workshops until after Henry Maudslay's "Lord Chancellor" bench micrometer circa 1805.

author: tautech
author_rank: Super Contributor
timestamp: August 26, 2016, 07:27:10 pm
content: Quote from: b_force on August 26, 2016, 06:29:51 pmDepends entirely on who set your PC up.ALL my equipment shows day/month/year, isn't that theproperway.

author: Kleinstein
author_rank: Super Contributor
timestamp: August 26, 2016, 07:52:20 pm
content: At least the US have adopted metric inches.So one inch is exactly 25.4 mm and no more need to conserve a kings thumb.You can do science / engineering with imperial units. However the units for something like thermal conductivity gets really strange. (e.g. BUT/s/F*inch or even versions with inch/square feet). So you may need different tables for different applications.Also metric threads are usually stronger than the imperial ones. So M6 screws are usually stronger than 1/4" despite of slightly smaller size. Using decimal inches all over could work, but there are still binary fractions (e.g 5/64") and decimal values mixed and for the small drills they have the strange number system instead. So who knows if a No 42 drill is large or smaller than 0.1 inch or 7/64".Even the EU has not fully converted to metric: pipe threads or still usually imperial. Here the communist block was ahead - they had metric thread for pipe work too.

author: edy
author_rank: Super Contributor
timestamp: August 26, 2016, 08:40:18 pm
content: I have a Chinese ruler ([EDIT: presume made in China but I could be mistaken]) that has CENTIMETERS on one side, and INCHES on the other side... except the inches are divided into 1/10 minor tick-markings! Not 1/8th or 1/16th.... Whats up with that?It has the logo "Support your local public schools" and is sponsored by Kentucky Fried Chicken's "S'cool Life Fund".http://www.scoollifefund.ca/. I'd like to know if I am the only one to have ever seen a 1/10th graded INCH scale or if this is found anywhere else?See the attached photos....

author: Karel
author_rank: Super Contributor
timestamp: August 26, 2016, 08:40:46 pm
content: It can be even more crazy than the imperial system. For example, the way the diameter of a cal. 12 shotgun was "calculated":Take a pound of lead, divide it in 12 parts, make a perfect ball of a part and that ball will fit in the barrel...https://en.wikipedia.org/wiki/Gauge_(bore_diameter)

author: IanB
author_rank: Super Contributor
timestamp: August 26, 2016, 09:02:52 pm
content: Quote from: edy on August 26, 2016, 08:40:18 pmYes, I can buy one in Staples. It is called an engineer's rule.

author: Zero999
author_rank: Super Contributor
timestamp: August 26, 2016, 09:06:48 pm
content: Here in the UK, it's common to find rules with cm on one side and inches on the other, with the first six inches divided into 16 and the remaining divided into 10. It's also common for the first inch to be divided into 32 and the first 50mm to have increments of 0.5mm.

author: Cerebus
author_rank: Super Contributor
timestamp: August 26, 2016, 09:18:47 pm
content: Quote from: m98 on August 26, 2016, 10:53:41 amWhen I bend my left thumb, the crease on the nail side of the joint is exactly one inch from where my nail seperates from the nail bead. Has been since I was about 18. Gives a whole new meaning to rule of thumb.

author: wilhelm
author_rank: Contributor
timestamp: August 26, 2016, 09:20:13 pm
content: https://youtu.be/pikrntjcbyw

author: bitslice
author_rank: Frequent Contributor
timestamp: August 26, 2016, 09:30:35 pm
content: Is America ever likely to change though? There is a lot invested in their system, it's not like the UK with dropping our farthing/sixpence or changing over to £/kg for cheese.

author: Cerebus
author_rank: Super Contributor
timestamp: August 26, 2016, 09:37:28 pm
content: Quote from: edy on August 26, 2016, 08:40:18 pmMy everyday engineering ruler has mm and 1/2 mm scales on one side, on the other side are two inch scales, one with three inches of 1/32, one inch of 1/64 and eight inches of 1/16, the other with 3 inches of 1/20, one inch of 1/50, one inch of 1/100, and seven inches of 1/10.

author: tautech
author_rank: Super Contributor
timestamp: August 26, 2016, 09:40:39 pm
content: Quote from: Karel on August 26, 2016, 08:40:46 pmYep, all shotguns except the 410 are determined that way.Only the .410 is a true calibre measurement.

author: IanB
author_rank: Super Contributor
timestamp: August 26, 2016, 09:41:08 pm
content: Quote from: bitslice on August 26, 2016, 09:30:35 pmWe (Britain) changed from imperial to metric in the 60's, so it can be done. There was similarly a lot invested, since Britain still had a manufacturing industry back then. But I think it happened in Britain because the interfering busybodies in the government mandated it.

author: Cerebus
author_rank: Super Contributor
timestamp: August 26, 2016, 09:44:50 pm
content: Quote from: bitslice on August 26, 2016, 09:30:35 pmA lot invested? A bit over a couple of hundred years. The UK had perhaps a thousand years invested in the imperial measurement system and even with our naturally conservative character we managed to change. Admittedly we did keep imperial units for the things that really matter, speed and beer.

author: tautech
author_rank: Super Contributor
timestamp: August 26, 2016, 09:48:45 pm
content: Quote from: IanB on August 26, 2016, 09:41:08 pmMore like the UK wanted greater acceptance from the EU before they joined and as we were close trading partners at that time got dragged into metric too.Now with Brexit maybe they'll consider turning the clock back and side more with the US system.

author: Monkeh
author_rank: Super Contributor
timestamp: August 26, 2016, 09:51:04 pm
content: Quote from: tautech on August 26, 2016, 09:48:45 pmWhy the **** would we do that?

author: edy
author_rank: Super Contributor
timestamp: August 26, 2016, 09:56:57 pm
content: In China it seems the units all became metric but they were using these before:Cun = Chinese inchhttps://en.wikipedia.org/wiki/Cun_(unit)Chi = Chinese foothttps://en.wikipedia.org/wiki/Chi_(unit)Zhang = 10 Chihttps://en.wikipedia.org/wiki/Zh%C3%A0ngBut then they would have decimal grades between units, like in metric....So 10 Cun = 1 Chi, and 10 Chi = 1 Zhang. Also, 1/100 of a Chi would be a fen, which is 1/10 of a Cun.Apparently, in Chinese the idiom "dé cùn jìn chi", literally: "gaining a cun and ask for a chi" means "extremely greedy". (from Wikipedia).... seems backwards, so in English it would sound more like "ask for a foot and gain an inch".

author: jtu
author_rank: Unknown
timestamp: August 26, 2016, 10:20:00 pm
content: I noticed this discussion lacks a view from some parts of the world, so I'm adding one from the post Soviet geography.There (here) are just no other measurement units than SI. Not in peoples heads, not in shops, not in school, not in science, nowhere.Well almost, we mostly have imported plumbing and water distribution systems parts (in inches) and that's probably the reason why plumbing is the only thing I don't DIY in my houseJust because I don't grasp it.Of course, we import not just plumbing and water distribution parts, there are some other cases too. For example, my lawn mower, it is mostly (SI) assembled, but the engine comes from the US. What is the result? All you hear in my backyard is swearing and a bolt with cut corners when it comes to the wrench size of 3/8.I simply can't think of PCB in 0.1 inch scale, it's 2.54mm (because of the historical reasons).I bought a ruler marked for both SI and imperial recently. Have I used the imperial side of it? No.I accept that there are units of measurement coming from the development history of the homo sapiens because our feet came out as prolonged as they came out. But hey, we have developed to the level, where it does not matter anymore. We really need a standard in order for people to talk the same language around the world. Is it SI? I'm used to it, but I don't care as long it is practical, logical and understood by everybody!

author: IanB
author_rank: Super Contributor
timestamp: August 26, 2016, 10:20:46 pm
content: Quote from: edy on August 26, 2016, 09:56:57 pmI don't think you have the right translation. Apparently this saying is equivalent to the English idiom, "Give someone an inch and they will take a mile."

author: Maxlor
author_rank: Frequent Contributor
timestamp: August 26, 2016, 11:20:26 pm
content: Quote from: digsys on August 26, 2016, 03:47:31 pmIt occurred to me just now that tire size specifications are quite odd. You might see something like 245/40/R18 here, which means the tire is 245cm wide, the sidewall is 40% of that high, and it fits on an 18 inch rim. Quite an odd mix of different units.Is an all-imperial system used in the US for tire size specs?

author: IanB
author_rank: Super Contributor
timestamp: August 26, 2016, 11:25:43 pm
content: Quote from: wraper on August 26, 2016, 10:46:54 pmSo did anyone spot a minor technical error contained within it? (OK, a bit of pedantry, but still...)

author: IanB
author_rank: Super Contributor
timestamp: August 26, 2016, 11:27:05 pm
content: Quote from: Maxlor on August 26, 2016, 11:20:26 pmNo, the US uses the same system. It's possibly even a world-wide standard.

author: b_force
author_rank: Super Contributor
timestamp: August 27, 2016, 12:34:36 am
content: Quote from: wraper on August 26, 2016, 10:46:54 pmThe last part is a good example of a fallacy*.You could still use metric for all the other billions of reasons.If it was true, a lot of other companies would have similar problems and they don'tAlso, there a many ways to work around it (or just keep calling some specific things by the old name, which also happens in other countries)*the seem to be really masters in that

author: Brumby
author_rank: Unknown
timestamp: August 27, 2016, 03:27:35 am
content: Quote from: Maxlor on August 26, 2016, 11:20:26 pm(ahem)

author: Brumby
author_rank: Unknown
timestamp: August 27, 2016, 03:34:14 am
content: Quote from: ajb on August 26, 2016, 01:42:34 pmOK .... go theotherway.0.625 = ? (This is only trivial because it's a commonly known value)Try0.469 ....0.731 .....

author: Brumby
author_rank: Unknown
timestamp: August 27, 2016, 03:41:45 am
content: Quote from: IanB on August 26, 2016, 06:54:36 pmWhile I agree there is no 'stunning advantage' - I would like to limit that to the fundamental of the reference unit (foot, inch, pound etc.) Where the real advantage lies is in the use of a decimal system - and that you have clearly stated.I would suggest that the next logical step is to adopt a system where this is the norm.

author: Zero999
author_rank: Super Contributor
timestamp: August 27, 2016, 09:17:30 am
content: Quote from: Brumby on August 27, 2016, 03:41:45 amI agree, the unit itself is unimportant. It's decimalisation which makes things easier. The problem with the imperial system, is there are so many damn units, with totally random relationships between them. For example, it would be fine if we got rid of feet, inches and just used yards, with with other units replaced with factors of ten, i.e. milli-yards, kilo-yards etc. but that's not gong to happen.

author: Jeroen3
author_rank: Super Contributor
timestamp: August 27, 2016, 09:33:24 am
content: This discussion is pointless. Why not ask why the UK drives on the wrong side?Would yield the same 20 pages of flaming.

author: firewalker
author_rank: Super Contributor
timestamp: August 27, 2016, 09:36:43 am
content: What is the definition of one inch?Alexander.

author: rs20
author_rank: Super Contributor
timestamp: August 27, 2016, 09:57:21 am
content: Quote from: firewalker on August 27, 2016, 09:36:43 amThe distance travelled by a beam of light in a vacuum after 16678060497 / 21413747000 ( approx = 0.7788 ) periods of the radiation corresponding to the transition between the two hyperfine levels of the ground state of the caesium 133 atom.

author: meeder
author_rank: Regular Contributor
timestamp: August 27, 2016, 10:21:26 am
content: Mixtures are always fun...Car tyres for example use millimeters for the with but the rims are measured in inches (both diameter and width).My sport (archery) is especially fun. Draw weight is in lbs, bow lenght, arrow length and draw lenght are in inches. Brace height in centimeters and nocking point height in millimeters.

author: bitslice
author_rank: Frequent Contributor
timestamp: August 27, 2016, 10:39:00 am
content: Quote from: meeder on August 27, 2016, 10:21:26 amThe history behind that situationhttp://www.madsci.org/posts/archives/2001-03/985878609.Sh.r.html

author: mathsquid
author_rank: Frequent Contributor
timestamp: August 27, 2016, 12:57:16 pm
content: Quote from: Brumby on August 27, 2016, 03:34:14 amWhen things need to be that precise, they are given in thou/mils. Look at the graduations on practically any machine tool.

author: Brumby
author_rank: Unknown
timestamp: August 27, 2016, 02:18:37 pm
content: Quote from: mathsquid on August 27, 2016, 12:57:16 pmWhat about precision? Precision was not the point of the statement.0.469 is 15/32 (very close). That is ruler measurable.That's the point. Conversion is NOT straightforward.

author: Homer J Simpson
author_rank: Super Contributor
timestamp: August 27, 2016, 02:42:57 pm
content: Metric System Thriving In Nation's Inner Citieshttp://www.theonion.com/article/metric-system-thriving-in-nations-inner-cities-458

author: Brumby
author_rank: Unknown
timestamp: August 27, 2016, 02:54:00 pm
content: OK .... that was worth a LOL.

author: Zero999
author_rank: Super Contributor
timestamp: August 27, 2016, 04:16:47 pm
content: Quote from: Homer J Simpson on August 27, 2016, 02:42:57 pmQuotelol.

author: nctnico
author_rank: Super Contributor
timestamp: August 27, 2016, 04:44:28 pm
content: Quote from: Jeroen3 on August 27, 2016, 09:33:24 amProbably because they don't like tourists! One of my kids wants to visit a place in the middle of nowhere in the UK. Normally I'd take the car and drive over there but since I really don't trust myself driving on the wrong side of the road when it is quiet we have to take the frickin' train for several hours.

author: IanB
author_rank: Super Contributor
timestamp: August 27, 2016, 05:23:08 pm
content: Quote from: nctnico on August 27, 2016, 04:44:28 pmHave you driven on the left before? It shouldn't take too long to get used to. A good way to make it easier is to follow the lead of other drivers.

author: Zero999
author_rank: Super Contributor
timestamp: August 27, 2016, 05:26:25 pm
content: Quote from: IanB on August 27, 2016, 05:23:08 pmI think that's the problem: driving on the other side of the road when it's not busy. When no one else is around, it must be easy to, out of habit, drift onto the wrong side of the road, then all of a sudden a car comes in the other direction.

author: nctnico
author_rank: Super Contributor
timestamp: August 27, 2016, 05:55:36 pm
content: Quote from: IanB on August 27, 2016, 05:23:08 pmI have driven on the left through Jakarta but that is easy: you just go with the flow because there is nowhere else to go. I'm mostly worried about an empty 2 lane road and/or moving onto the right lane due to some automatic reaction in a situation which requires a 'quick adjustment'.

author: Jeroen3
author_rank: Super Contributor
timestamp: August 27, 2016, 06:19:52 pm
content: The worst part of it: the stick is on the wrong side. You have to get an automatic rental. Which is expensive.

author: Ian.M
author_rank: Super Contributor
timestamp: August 27, 2016, 06:21:34 pm
content: Quote from: nctnico on August 27, 2016, 04:44:28 pmNo. Its actually because the Brits didn't like Napoleon or Hitler!http://books.google.co.uk/books?id=qfak8nsMNGIC&pg=PA16&lpg=PA16#v=onepage&q&f=false

author: jonovid
author_rank: Super Contributor
timestamp: August 27, 2016, 06:40:44 pm
content: Inches ? its a North American thing the world is now metric A disaster investigation board reports that NASA’s Mars Climate Orbiter burned up in the Martian atmosphere because engineers failed to convert units from American to metric.

author: nctnico
author_rank: Super Contributor
timestamp: August 27, 2016, 06:46:55 pm
content: Quote from: Jeroen3 on August 27, 2016, 06:19:52 pmThat is not a problem at all (at least for me when driving in Jakarta). The worst thing is that the indicators and light controls are on the wrong side as well. But I'd go with my own car anyway.

author: b_force
author_rank: Super Contributor
timestamp: August 27, 2016, 06:50:03 pm
content: Worst is going back to a right driving country while being in a left driving country for a long timeI still struggle in some situations. (like total brain lock up)I don't think there is wrong or right in this. It's about convenience.But I guess some countries are simply too stubborn.

author: IanB
author_rank: Super Contributor
timestamp: August 27, 2016, 06:52:54 pm
content: Quote from: nctnico on August 27, 2016, 06:46:55 pmOh? These days every car I have encountered has the indicator stalk on the left and the wiper stalk on the right.

author: Zero999
author_rank: Super Contributor
timestamp: August 27, 2016, 07:11:55 pm
content: Quote from: Jeroen3 on August 27, 2016, 09:33:24 amI think that's totally different.With imperial vs metric, it's easy to choose and both can easily be used, so long as the units are defined. As far as which side of the road to drive on is concerned: everyone on the same road network must do the same, otherwise chaos would ensue.Why hasn't the UK changed to driving on the right hand side? Probably because it would be too costly and the sudden increase in accidents that would follow when people forget.The UK changed to metric, as far as trade and industry are concerned, yet all the road signs are still in imperial, most likely for the same reason as above. I don't see why the US can't do the same, even if it is slowly phased in over a long period of time.

author: tautech
author_rank: Super Contributor
timestamp: August 27, 2016, 07:22:22 pm
content: Quote from: IanB on August 27, 2016, 06:52:54 pmHa, most here are the opposite. Indicator right and wiper left, isn't that the correct way?Most southern hemisphere built cars are this way and the first time I encountered the reverse was in a UK assembled Mk 2 Escort Sports I had for a while 30 yrs back. Previous to that I had a couple of locally assembled Mk 3 Cortina's and they both were indicator on the right.

author: IanB
author_rank: Super Contributor
timestamp: August 27, 2016, 07:38:17 pm
content: Quote from: tautech on August 27, 2016, 07:22:22 pmUsually I would say the indicator stalk should be on the opposite side from the gear stick so you can operate the indicators while changing gear. So ideally, British cars would have the indicator on the right. However, since mainland Europe has the gear stick on the right the auto manufacturers seem to have standardized on putting the indicator stalk on the left for all markets. Presumably it is easier to manufacture the wheel assembly that way without needing to make two versions of it.

author: zapta
author_rank: Super Contributor
timestamp: August 27, 2016, 09:33:46 pm
content: Quote from: Brumby on August 26, 2016, 12:15:49 pmLet me guess, you specify all your capacitors in pf.

author: Brumby
author_rank: Unknown
timestamp: August 28, 2016, 12:41:54 am
content: In the range of 10-12F to 10-9F, yes.Sometimes up to 10-8F.But you attempt at being 'clever' fails.The straw man is really getting a workout...!

author: Brumby
author_rank: Unknown
timestamp: August 28, 2016, 12:45:44 am
content: Quote from: jonovid on August 27, 2016, 06:40:44 pm"American"?Is the Imperial system now so on the outer that it's very name is fading from consciousness - and the system is now identified by it's minority user base?

author: guido
author_rank: Regular Contributor
timestamp: August 28, 2016, 01:01:02 am
content: I once was in the west of Ireland on a short holiday trip after a course in Dublin (those were the days..). We went out with some french girls in the evening and there was no pub in the village we were staying. So we drove with them to the next village a fewkilometersmiles away in their little Peugot. About half way we decided it would probably be better to drive on the other side of the roadLuckily there is no traffic in those parts of Ireland.Later i had a girlfriend for years from Dublin. She always talked about stones when she was talking about her weight (woman..). No idea at all what she was on about, the numbers did not say anything to me.By the way, they are going to change to right side driving in the UK too. Busses and lories first

author: zapta
author_rank: Super Contributor
timestamp: August 28, 2016, 01:13:06 am
content: My metric drill bit set. Got it at a local hardware store.

author: Brumby
author_rank: Unknown
timestamp: August 28, 2016, 01:25:04 am
content: OK.... I'll pay that.An interesting size selection. That's the Imperial compatible set, isn't it?

author: IanB
author_rank: Super Contributor
timestamp: August 28, 2016, 01:55:27 am
content: Quote from: Brumby on August 28, 2016, 12:45:44 amThe Imperial system of measurement is (was) used by the UK and by British Commonwealth countries. The USA uses the US Customary system of measurement. They are similar but not identical. For instance, one US ton is 2000 lb, but one Imperial ton is 2240 lb. One Imperial fluid ounce is equal to 0.96076 US fluid ounces. Not to mention that one Imperial pint is 20 fluid ounces, whereas one US pint is 16 fluid ounces.

author: zapta
author_rank: Super Contributor
timestamp: August 28, 2016, 02:38:32 am
content: Quote from: Brumby on August 28, 2016, 01:25:04 amHardware store here don't carry metric drill bits and 95% of the tape rulers are imperial only. Surprisingly enough, the sun is shining, the birds are chirping, and the illegals metrics at the southern boarder keep flowing in.

author: Brumby
author_rank: Unknown
timestamp: August 28, 2016, 03:49:46 am
content: Quote from: IanB on August 28, 2016, 01:55:27 amI was forgetting.Thank you. I stand corrected.

author: Brumby
author_rank: Unknown
timestamp: August 28, 2016, 03:54:53 am
content: Quote from: zapta on August 28, 2016, 02:38:32 amThere's no argument imperial measurements work - and for those familiar with them, to change might seem ridiculous - but I believe the metric system will eventually take over for all but some well established examples, such as altitude for aircraft. Some places will take longer than others ... but it will happen.

author: ivaylo
author_rank: Frequent Contributor
timestamp: August 28, 2016, 06:51:42 am
content: Quote from: Jeroen3 on August 27, 2016, 06:19:52 pmI could deal with that the few times I rented a car in the UK. Even the two lane, six way roundabouts could be navigated with a decent app and a watchful wife. Wasn't tempted to veer on the other side either. My biggest problem, I figured, on the narrow roads in Schottland (really, anything rural there is more like one lane) was that sitting on the wrong side I had no size perception for the opposite side of the vehicle. Kept missing the road, super scary... I thought myself an OK driver, never realized vehicle size perception could be so asymmetric.

author: zapta
author_rank: Super Contributor
timestamp: August 28, 2016, 07:04:24 am
content: Quote from: Brumby on August 28, 2016, 03:54:53 amAny specific timeframe or is it an open ended prophesy?

author: AntiProtonBoy
author_rank: Frequent Contributor
timestamp: August 28, 2016, 09:07:57 am
content: Quote from: m98 on August 26, 2016, 10:53:41 amFucking penguins, man.

author: Brumby
author_rank: Unknown
timestamp: August 28, 2016, 09:08:30 am
content: Quote from: zapta on August 28, 2016, 07:04:24 amPutting a timeframe on it is a risky exercise - but I'll go with this....2 generations after the last class on weights and measures has moved to metric.

author: Jeroen3
author_rank: Super Contributor
timestamp: August 28, 2016, 11:25:05 am
content: Isn't it part of the "make america great again" plan? They used metric to land people on the moon, now they rely on metricheskiy to get people to space.this forum does not handle cyrillic very well:??

author: madires
author_rank: Super Contributor
timestamp: August 28, 2016, 12:03:16 pm
content: Quote from: AntiProtonBoy on August 28, 2016, 09:07:57 amThe map seems to be a tad outdated. Fromhttps://en.wikipedia.org/wiki/Myanmar_units_of_measurement:Quote

author: doobedoobedo
author_rank: Regular Contributor
timestamp: August 28, 2016, 12:37:36 pm
content: Driving on the wrong side of the road is not a problem when driving abroad. However if you get a lift with someone it's hard not to head straight for the driver's seat.Gallons seem to cause the most confusion for Europeans when talking to a Brit, they seem to be under the impression that a gallon is ~3.79l (US) when it is actually ~4.54l (imperial).

author: poorchava
author_rank: Super Contributor
timestamp: August 28, 2016, 01:34:33 pm
content: Thing I wonder the most is why here in Poland and some neighboring countries (Czech Republic, Slovakia etc) most plumbing dimensions are in inches (eg a common size for the pipe that connects toilet reservoir to the water supply is 1/2 or 3/8 of an inch)Wys?ane z mojego HTC One M8s przy u?yciu Tapatalka

author: madires
author_rank: Super Contributor
timestamp: August 28, 2016, 01:43:01 pm
content: You can blame Sir Joseph Whitworth for that.

author: Brumby
author_rank: Unknown
timestamp: August 28, 2016, 01:45:55 pm
content: Hey!Sir Joseph was a good guy!!

author: b_force
author_rank: Super Contributor
timestamp: August 28, 2016, 01:53:41 pm
content: It's actually remarkable funny that the ratio of the votes is not so far off from the map image/real number.

author: nctnico
author_rank: Super Contributor
timestamp: August 28, 2016, 04:16:51 pm
content: Quote from: poorchava on August 28, 2016, 01:34:33 pmIn the EU water piping is a hit&miss. It basically comes down to every country having it's own 'standard' sizes.

author: meeder
author_rank: Regular Contributor
timestamp: August 28, 2016, 05:35:17 pm
content: Waterpipes are metric here in the Netherlands.

author: IanB
author_rank: Super Contributor
timestamp: August 28, 2016, 07:53:00 pm
content: Quote from: nctnico on August 28, 2016, 04:16:51 pmI do not think this is so (see below).Quote from: meeder on August 28, 2016, 05:35:17 pmGenerally speaking, pipe sizes may be quoted in metric or traditional units, but either way it will be the same pipe. For example, a one inch nominal bore pipe may also be described in metric as a DN 25 mm pipe.Such a pipe may have a variety of actual bore sizes and wall thicknesses according to the schedule (strength, or pressure rating of the pipe). There is an ISO standard for these sizes. For example, here is a table showing standard sizes in traditional and metric units:http://dacapo.com/uploads/documents/35-document.pdfSince pipes may be manufactured and shipped internationally, it would be very inconvenient if the sizes were not standardized.

author: ivaylo
author_rank: Frequent Contributor
timestamp: August 28, 2016, 08:09:23 pm
content: Quote from: nctnico on August 28, 2016, 04:16:51 pmYes, and some places still using the obsolete German Zoll measure -https://en.m.wikipedia.org/wiki/Obsolete_German_units_of_measurement, which seems to be an inch, but with a few alternate definitions.

author: Ian.M
author_rank: Super Contributor
timestamp: August 28, 2016, 08:19:30 pm
content: Metric and imperial copper water pipe are *NOT* compatible. You need adapters to reliably couple one to the other using compression fittings. Seehttp://www.wosupply.com/pdf/1_General_Products_82511_115.pdfIts normally close enough to bodge for low pressure work by swaging or expanding the pipe end when using solder fittings without solder preforms.

author: TimFox
author_rank: Super Contributor
timestamp: August 28, 2016, 09:32:48 pm
content: Let us not forget the standard tripod-mount screw thread for cameras, as found in several camera manuals: M6.3 (otherwise known as 1/4-20 UNC).

author: nctnico
author_rank: Super Contributor
timestamp: August 28, 2016, 09:54:56 pm
content: Quote from: IanB on August 28, 2016, 07:53:00 pmYou may wish but you can find various sizes of copper tubing in the EU for tap water: 8, 10, 12, 14, 15, 16, 20 and 22mm. And that is just copper tubing!

author: Monkeh
author_rank: Super Contributor
timestamp: August 28, 2016, 10:07:40 pm
content: In the UK you'll typically find 15, 22, 28, 35..We'll not speak of microbore.

author: nctnico
author_rank: Super Contributor
timestamp: August 28, 2016, 11:07:57 pm
content: I always specify PCB plating thickness in um (micro-meters).

author: VK5RC
author_rank: Unknown
timestamp: August 29, 2016, 04:55:43 am
content: +1 blueskull, metric is great for accuracy, imperial great for rough measures eg "6 foot high" and lathe work! Whitworth understood that well

author: VK3DRB
author_rank: Super Contributor
timestamp: August 29, 2016, 12:59:43 pm
content: The three remaining countries who still use ye olde imperial system are the three amigos: The USA, Liberia and the Myanmar. Maybe they should form a new trading bloc, called the blocheads.There is no reason why anyone should still be laying out PCB's using imperial measurements, except as an excuse for being mentally challenged maybe.

author: m98
author_rank: Frequent Contributor
timestamp: August 29, 2016, 02:07:02 pm
content: Quote from: blueskull on August 28, 2016, 10:58:39 pmSo why would you specify thickness via area density? This might make sense for people searching some mental calculation challenges throughout the day...I use µm for that. But I do actually use imperial units quite frequently, as I'm forced to use them in aviation. Well, I do understand that switching measuring systems here is, unfortunately, a bit impractical.

author: digsys
author_rank: Unknown
timestamp: August 29, 2016, 02:13:44 pm
content: Quote from: VK3DRBThat's uncalled for. At least try to be civil.

author: boffin
author_rank: Unknown
timestamp: August 29, 2016, 03:57:08 pm
content: Quote from: VK3DRB on August 29, 2016, 12:59:43 pmActually Myanmar is switching to Metric, there will only be two left.https://en.wikipedia.org/wiki/Myanmar_units_of_measurement#Adoption_of_SI_.28Metric.29_SystemHere in Canada we have an interesting dilemma. So much of our commerce and systems are with the USA, that lots of imperial things remain, especially in industries like construction.Pipe is still in inches (fractional inches)Machine Screws are typically UNC (#8/32, #10/32, etc)Houses are still built on 16" centres between studs.Some things are even uniquely Canadian, like a most wood screws have a Robertson head.but my favourite example is seeing plywood advertised in the store as: 4 foot by 8 foot by 19 mmI'd love to see everything go Metric, but it's hard when there's so much out there that is imperial. How big are the tires on your car 205/60 R15. The 205 is mm , the R15 is inches. Now that's screwed up.And don't even get me going about aviation where you have feet (altitude), metres(altitude in some places, visibility in some places), statute miles (visibility), nautical miles/hr (wind speed), degrees true (some wind direction), degrees magnetic (wind direction at airports, runways), pounds (weight of fuel), litres (what you buy your fuel in), gallons per hour (what you consume your fuel as) and so on...It's amazing there aren't more accidents like Air Canada 143 where they loaded a plane with lbs instead of kgs of fuel.

author: zapta
author_rank: Super Contributor
timestamp: August 29, 2016, 04:12:06 pm
content: Quote from: boffin on August 29, 2016, 03:57:08 pmThat's an amazing story. 0 fatalities.https://en.wikipedia.org/wiki/Gimli_Glider

author: Back2Volts
author_rank: Unknown
timestamp: August 29, 2016, 04:53:08 pm
content: I grew up with metric and used it for half of my life until I moved to the US. Today I am used to inches and feet, which I use regularly for most everything except when dealing with small measurements, where I may go to millimeters.The imperial system is clearly superior! See you guys in a while, I am going for lunch to have a 0.257 BTU veggie sandwich and a 0.05 BTU diet soda

author: Homer J Simpson
author_rank: Super Contributor
timestamp: August 29, 2016, 07:41:29 pm
content: https://youtu.be/LdnmNLDvZFo

author: boffin
author_rank: Unknown
timestamp: August 29, 2016, 08:02:06 pm
content: Quote from: zapta on August 29, 2016, 04:12:06 pmOh, and AC drove from their maint base in Winnipeg out to Gimli to fix the plane, and the maintenance guys ran out of gas on the way.C-GAUN went on to another 20ish years of service with AC, after relatively minor repairs.Canadians seem uniquely qualified at the task of landing widebody aircraft with zero fuel, see Air Transat 236:https://en.wikipedia.org/wiki/Air_Transat_Flight_236(which is even more amazing than ACA143)

author: R005T3r
author_rank: Frequent Contributor
timestamp: August 29, 2016, 08:33:12 pm
content: According to wikipedia, the 94% of the world population uses mm instead of inches... However, what system is used in Antarctica?

author: Cerebus
author_rank: Super Contributor
timestamp: August 30, 2016, 12:19:18 am
content: Quote from: R005T3r on August 29, 2016, 08:33:12 pmBy the minority population - SI units, as all the people on Antarctica are scientists. By the majority? Penguins, so probably fish based units.

author: thunderbuny
author_rank: Contributor
timestamp: August 30, 2016, 03:41:34 am
content: 3 eights? 2 quarters!???that is waaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaay to complialienated!metric much better!and not complialienated!

author: zapta
author_rank: Super Contributor
timestamp: August 30, 2016, 03:57:57 am
content: Quote from: ProBang2 on August 26, 2016, 01:02:18 am"der Narzissmus der kleinen Differenzen"

author: netdudeuk
author_rank: Frequent Contributor
timestamp: August 30, 2016, 10:06:47 pm
content: Both. If something looked to be an inch long I'd say 'inch' (not 25.4 mm) and if it looked two mm long I'd say 'two mm' (not twelfth of an inch). Etc ...

author: ebclr
author_rank: Super Contributor
timestamp: August 31, 2016, 11:35:29 am
content: I would suggest that make a GDP adjustment on the results of this research mm/inchesOn this way i guess more money is using inches than mm

author: Kremmen
author_rank: Super Contributor
timestamp: August 31, 2016, 12:20:56 pm
content: What? No - EU region is almost as big as USA; add China and USA is leftfarclearly behind:https://en.wikipedia.org/wiki/List_of_countries_by_GDP_(nominal)That assuming USA is the only significant imperial units nation and the rest are metric.

author: IanB
author_rank: Super Contributor
timestamp: August 31, 2016, 02:15:26 pm
content: Quote from: blueskull on August 31, 2016, 12:40:16 pmScience may use SI units, but engineering and industry very definitely use US customary units.

author: Cerebus
author_rank: Super Contributor
timestamp: August 31, 2016, 04:26:09 pm
content: Quote from: IanB on August 31, 2016, 02:15:26 pmBy 'engineering' one must assume you mean mechanics (as in car mechanic, washing machine mechanic) because I'm pretty sure that no mechanicalengineeris going to use units like slugs or poundals if they retain any vestige of sanity.

author: IanB
author_rank: Super Contributor
timestamp: August 31, 2016, 05:19:21 pm
content: Quote from: Cerebus on August 31, 2016, 04:26:09 pmI work in the chemical/process industries. It is universal in the USA for mechanical and process engineers, in both design and operation, to use inches, feet, pounds, psi, gallons, degrees Fahrenheit, BTUs, horsepower, and so on. Slugs and poundals are not part of the customary system of units, so no, you won't find those. But you won't find SI units in general use either.

author: rrinker
author_rank: Super Contributor
timestamp: August 31, 2016, 07:10:00 pm
content: I take it none of you has bothered to work on an American made car in the past 10 years or so? Almost all metric bolts. I had to buy a set of metric wrenches for a car built and assembled in Illinois.

author: IanB
author_rank: Super Contributor
timestamp: August 31, 2016, 07:15:49 pm
content: Quote from: rrinker on August 31, 2016, 07:10:00 pmBecause "American" cars now have worldwide content I suppose. Maybe commerce will do for metrication what the government has failed to do?

author: Cerebus
author_rank: Super Contributor
timestamp: August 31, 2016, 09:06:06 pm
content: Quote from: IanB on August 31, 2016, 05:19:21 pmChemical process? What mass unit do you use for a Mole?I really can't imagine quite how masochistic you have to be to do any real engineering in non-SI units. Carpentry, yes, heat flow, no. I'm old enough to have been schooled in both Imperial and metric units and I'll happily hack timber about in feet and inches, but the second I have to do anything that counts as more than mere arithmetic I go metric. I find it quite amusing that one of the last vestiges of the British Empire is American engineers using BRITISH Thermal Units.

author: IanB
author_rank: Super Contributor
timestamp: August 31, 2016, 09:12:19 pm
content: Quote from: Cerebus on August 31, 2016, 09:06:06 pmThe lb-mol. Such that 1 lb-mol of hydrogen has a mass of 2 lb.Yes, it's ugly, and being British I find it amusing. But, it's real. Engineers here really do work in these units, strange as it may seem.(But I'll let you into a secret. When we write design software we code it to work in SI units internally, and then we do the unit conversions for display)

author: mtdoc
author_rank: Super Contributor
timestamp: September 01, 2016, 06:02:51 am
content: Quote from: IanB on August 31, 2016, 02:15:26 pmScience and medicine in the US use metric/SI units. They always have AFAIK. For certain they have for the past 50 years. I did not realize this was not true in some engineering fields.I remember when I was in the 6th grade (1974) - they started teaching us the metric system in school and told us that the US would convert to the Metric system by 1980. Of course that didn't happen.I use metric units daily in medicine - though there weight is often given in in lbs and converted to kg for calculating drug dosages or IV fluid calculations. Temperature may be specified in farenheit since that is what patient's are familiar with. People want to know their height in feet and inches but any calculations are always done using metric units for length.At home all woodworking and building projects are always done using feet and inches.I actually think it is benefit to have to go back and forth between metric and standard US imperial units. It's good exercise for the brain. It's like being bilingual. I feel sorry for those only fluent in one language of measurement!

author: zapta
author_rank: Super Contributor
timestamp: September 01, 2016, 12:08:17 pm
content: Quote from: rrinker on August 31, 2016, 07:10:00 pmI am using Metrinch. It's a 6 points wrench set that is designed to be both SAE and metric. Works very well for me.

author: Bendba
author_rank: Regular Contributor
timestamp: September 01, 2016, 12:59:30 pm
content: Hi.I'll have my say in that one, I grew up in metric (Belgium) and moved in Australia and started working with older farmers who don't understand metric. So I got used to go from one to the other but I do like the imperial system for a few things.For example when you work on older machines, the part sizes seem to be from only a few common values whilst machines made in metric, it's all over the place.Also you can easily divide an inch by 2, 4, 8, 16 and even 32 with just a ruler or a foot by 2, 3, 4, 6, 8, 12, 18, 24... but in metric, except for dividing by 2, 5 and 10, you always end up with decimals.Though sometime you measure something to be for example 17.5cm and you want to mark 2/3, it's easier to use the metric side of the rulerThe other funny thing is with mm and mils, there is a lot of confusion. If you go to the store and ask for a piece of brass sheet 15 mils thick, you could well be told that they don't have any thick brass plates. Same with rain gauges, when you get 3/8 inch of rain, most people say 10 mils instead of 10mm.Anyway, I like both systems I have I great time watching people getting confused between the two.By the way, it seems that a lot of SI units get written wrong in Australia. It is very common to see things like M or mtr for meter, ltr or L for liter, W/h or W/H for watt hour, Kg or KG for kilogram,... and so on.

author: b_force
author_rank: Super Contributor
timestamp: September 01, 2016, 01:51:12 pm
content: Ehm, you can also easily divide metrics on exactly the same way?Just by different numbers.I see a lot of confusion in this topic about standards vs other standards.It's about how to scale up or down, so the mathematical equation between mm, meters and kilometers vs thou, inch, feet, yard and miles

author: Bendba
author_rank: Regular Contributor
timestamp: September 01, 2016, 02:02:44 pm
content: Quote from: b_force on September 01, 2016, 01:51:12 pmI reckon that's just a mind set, depending what one is used to.Metric people don't like 1000 mils/inch, 12"/foot, 3 feet/yard yet I've never heard anyone complain about having 60'/h, 24h/day, 7 days/week, 28, 30 or 31 days per month and so on.

author: b_force
author_rank: Super Contributor
timestamp: September 01, 2016, 02:11:02 pm
content: Quote from: Bendba on September 01, 2016, 02:02:44 pmI don't know about you, but moving the decimal just a few spots is a billions times easier than dividing by 36And time and days is exactly a bad (one of a kind) example. Which I think is a cumbersome system.You get used to it, yes, but handy to use in programming etc, no not at all!

author: IanB
author_rank: Super Contributor
timestamp: September 01, 2016, 03:15:06 pm
content: Quote from: Bendba on September 01, 2016, 12:59:30 pmThat's probably because "mils" are an American unit and you are in Australia. In Britain and Australia when people want to talk about 1/1000 inch they would say "thou". So you want a brass sheet 15 thou thick, not 15 mils thick.

author: Maxlor
author_rank: Frequent Contributor
timestamp: September 01, 2016, 04:28:07 pm
content: Quote from: Bendba on September 01, 2016, 02:02:44 pmActually Swatch tried doing something about that around 20 years ago, by introducing watches that ran on "Internet Time". Those divide a day into 1000 equal units (so a unit equals 86.4 seconds). There also are no time zones, which makes sense for something called "Internet Time"I don't think they were serious about it even back then, and unsurprisingly, noone really cares about it. I do like the idea though, it certainly would make coordination easier (consider: "let's have our intercontinental conference call at @400" vs. "let's have our intercontinental conference call at 09:30 CET") and timestamps shorter ("@395.8" vs. "09:30:00 UTC+1")https://en.wikipedia.org/wiki/Swatch_Internet_TimeAs for the number of days in a month or yeah: blame the universe!

author: Zero999
author_rank: Super Contributor
timestamp: September 01, 2016, 04:44:39 pm
content: Quote from: Bendba on September 01, 2016, 02:02:44 pmI bet people who write software libraries for date calculations do. Calculating the date and time of day is a PITA, especially when you've got leap seconds as well as leap years to take account of. It's generally done by calculating everything internally in seconds or a fraction of a second and everything else is calculated from there.

author: rrinker
author_rank: Super Contributor
timestamp: September 01, 2016, 04:49:48 pm
content: Quote from: IanB on September 01, 2016, 03:15:06 pmYou really want to confuse someone, say that something has to be 2 tenths or so. In precision machining, that is 2 ten thousandths of an inch, not 2/10. Common in machine shops in the US to say "thou" as well for thousandths too.

author: Cerebus
author_rank: Super Contributor
timestamp: September 01, 2016, 07:22:39 pm
content: Quote from: mtdoc on September 01, 2016, 06:02:51 amAmerican medicine tends to use different units for biochemistry than the rest of the world. So, blood glucose units are in mmol/l here in the UK, but mg/dl in the US. Here, anything that can be expressed in mol/l generally will be whereas the Americans seem to prefer g/dl.

author: TimFox
author_rank: Super Contributor
timestamp: September 01, 2016, 07:28:09 pm
content: Does anyone else ever use "dl", rather than expressing the volume in "l" or "ml"?

author: Cerebus
author_rank: Super Contributor
timestamp: September 01, 2016, 07:29:55 pm
content: Quote from: IanB on September 01, 2016, 03:15:06 pmAnd to further the confusion the American military uses compasses with 'mils' instead of degrees.

author: Cerebus
author_rank: Super Contributor
timestamp: September 01, 2016, 07:33:20 pm
content: Quote from: Hero999 on September 01, 2016, 04:44:39 pmThe common base unit in most date and time libraries is the Julian Day and fractions thereof, usually represented as fixed point binary.

author: Cerebus
author_rank: Super Contributor
timestamp: September 01, 2016, 07:44:35 pm
content: Quote from: TimFox on September 01, 2016, 07:28:09 pmThe only people I've seen make regular use of decilitres and centilitres are the French.

author: IanB
author_rank: Super Contributor
timestamp: September 01, 2016, 08:12:33 pm
content: I've seen cl from time to time on drink labels, e.g. a bottle of spirits may be 70 cl, but I've rarely seen it anywhere else. Never dl though, that's an odd one.

author: tautech
author_rank: Super Contributor
timestamp: September 01, 2016, 08:51:43 pm
content: Quote from: Bendba on September 01, 2016, 02:02:44 pmExactly so.I commonly work in both mm and inches, fractions or decimal points make little difference IF you're using them frequently.For most non-precision measurement there are numerous dividers/multipliers that you only need to remember to get the job done. For simple length ~40" = 1 m (39.37 if you must) and therefore 1 mm ~=40 thou/mil.Start adding 0.1mm to anything and it's ~4 thou/mil ....pretty easy IMHO.The one that gets me always is pressure conversion, I use PSI as much as possible for the stupid metric nazis can't/won't manage to use one standard unit.MPa, kPa, Kg/cm3, Bar, Atm and so on. Yeah, while they all have something in common and usually convert by factors of 10 why on earth should one have to jump through mental hoops just to get to a unit that is common and makes sense like PSI.Even in industries that I'm involved in in NZ PSI is still the most common pressure measurement unit and that's after NZ went metric nearly 50 years ago.

author: IanB
author_rank: Super Contributor
timestamp: September 01, 2016, 08:55:57 pm
content: I mostly like kPa, but bar is good too (= 100 kPa).kg/cm² is a big no-no (= 98.0665 kPa), but they seem to like it in Japan. I wish they wouldn't...

author: tautech
author_rank: Super Contributor
timestamp: September 01, 2016, 09:00:59 pm
content: Quote from: IanB on September 01, 2016, 08:55:57 pm= 14.7 PSI or 1 Atm

author: Maxlor
author_rank: Frequent Contributor
timestamp: September 01, 2016, 09:07:57 pm
content: We use dl here too for specifying softdrink serving sizes, usually abbreviated to something like "2 dezi" when talking. It's entirely possible that this usage was imported from the french; germans were confused when I used the unit

author: Muttley Snickers
author_rank: Unknown
timestamp: September 01, 2016, 09:09:43 pm
content: The thickness of my wallet is measured in microns the majority of the time.

author: Bendba
author_rank: Regular Contributor
timestamp: September 01, 2016, 09:28:37 pm
content: Quote from: IanB on September 01, 2016, 03:15:06 pmThat'd explain a bit. Though I commonly hear mechanics talk in mils, especially for engine parts clearances

author: Red Squirrel
author_rank: Super Contributor
timestamp: September 01, 2016, 09:39:39 pm
content: I prefer mm/metric. With mm, you can easily convert to cm, metre etc without even having to think about it. Not so much with feet and inches. And fractions of inches can get pretty ugly to work with too.I hate that lot of construction materials still use imperial, would really be nice if they switched to a metric system. Would take a bit of getting used to and a transition since a 2x4 would not be a 2x4 anymore, and framing spacing and plywood sizes etc would be a bit different etc but it should be done.

author: Zero999
author_rank: Super Contributor
timestamp: September 01, 2016, 09:49:40 pm
content: Quote from: Cerebus on September 01, 2016, 07:33:20 pmComputer time is normally calculated in seconds, or fractions of. It wouldn't be very sensible to use fractions of a day in time calculations because a day isn't always 24*60*60 seconds long.The day isn't a fixed unit of time. It's an astrological phenomenon, which repeats approximately every 86.4k seconds.

author: Cerebus
author_rank: Super Contributor
timestamp: September 01, 2016, 11:32:03 pm
content: Quote from: Hero999 on September 01, 2016, 09:49:40 pmActually a day is a civil phenomenon and lasts exactly as long as the civilization that uses it defines. This varies with geography and historical time. In Rome the day 5th October 1582 lasted 0 seconds as did the following 9 days. To account for this and other awkward features like leap seconds you need to know the day, and Julian days are what get used. The classic text on this is a book called Calendrical Calculations by Rheingold, and it gets a mention in the source code comments of every date and time library I've ever had the misfortune to have to delve into.

author: Brumby
author_rank: Unknown
timestamp: September 02, 2016, 03:14:21 am
content: Quote from: tautech on September 01, 2016, 08:51:43 pmI must! I must!

author: sleemanj
author_rank: Super Contributor
timestamp: September 02, 2016, 04:16:08 am
content: Blood glucose is an interesting case, depending on the country you are in, either you will measure in mmol/L (millimole per litre), or in mg/dL (milligram per decilitre) - both more or less could be regarded as metric measurements (SI units, one is measuring molecular concentration, and the other mass concentration), there's no particular consensus worldwide as to which is "better" - the split between number of countries that use mmol/L and those that use mg/dL are about the same.Blood glucose meters typically will have the option to switch the units for you as a configuration option.FWIW, I use mmol/L.

author: Bendba
author_rank: Regular Contributor
timestamp: September 02, 2016, 07:03:06 am
content: Quote from: tautech on September 01, 2016, 09:00:59 pmActually, 1 bar is not equal to 1atm.1 bar = 100 kPa1 atm = 101.3 kPaPlus, a manometer with a atm scale will show 1 atm at atmospheric pressure whilst a manometer in bar will show 0If you want to complicate things a bit more, start using mm of Hg or torr. (Blood pressure in some country is measured in mm of Hg, in others, it is in cm of Hg)

author: GK
author_rank: Super Contributor
timestamp: September 02, 2016, 07:45:43 am
content: Quote from: ivaylo on August 26, 2016, 07:48:30 amDoesn't sound like that much of a nightmare. I've restored (as in every bolt) a 1968 Land Rover which is assembled with:1] BSP (British Standard pipe)2] BS-Conduit (British Standard conduit; don't confuse with BSC)3] BSF (British Standard fine)4] BSW (British Standard Whitworth)5] BA (British Association)6] UNC (Unified National Coarse)7] UNF (Unified National Fine)8] Assorted thread sizes in metric.1] is used for the water jacket plugs in the head, 2] is used for the block welch plugs. 3] is used throughout the engine gearbox and axles with 4] restricted to the trans-brake assembly IIRC. 5] is used almost exclusively for the gauges/instrumentation with a little 8] thrown in. The fuel line fittings to the Solex (French) carburetor are also 8]. 6] and 7] are used throughout the body. 7] for sizes equal to or more than 1/4" dia. are specified directly in fractions of an inch while smaller are specified in Gauge#.

author: Gromitt
author_rank: Regular Contributor
timestamp: September 02, 2016, 09:04:44 am
content: Quote from: Cerebus on September 01, 2016, 07:44:35 pmWe use dl and cl in Sweden too./stefan

author: Galenbo
author_rank: Super Contributor
timestamp: September 02, 2016, 10:18:22 am
content: Quote from: Maxlor on September 01, 2016, 04:28:07 pm360 is a nice number, I can live with the 1.4% error this gives.No one needs week or month.

author: Galenbo
author_rank: Super Contributor
timestamp: September 02, 2016, 10:26:44 am
content: Quote from: TimFox on September 01, 2016, 07:28:09 pmWe never use Kl, our culture obliges to use m3 in that case.Our local popular word for m3 is ""kuup", derivated from "cube"

author: b_force
author_rank: Super Contributor
timestamp: September 02, 2016, 10:36:05 am
content: Liters (and cl, dl etc) are actually not a SI unit, m^3 and dm^3 are.

author: Cerebus
author_rank: Super Contributor
timestamp: September 02, 2016, 11:53:16 am
content: Quote from: b_force on September 02, 2016, 10:36:05 amThe status of litres is interesting. It is not strictly an SI unit but the CIPM adopted litres as an alternative notation for dm^3 in 1879, this was confirmed by the CIPM in 1948 and again confirmed by the CGPM in 1979 (Resolution 6 of the 16th CGPM). The actually phrasing used in 1979 wasconsidering that the name litre, although not included in the Système International d'Unités, must be admitted for general use with the System,decides, as an exception, to adopt the two symbols l and L as symbols to be used for the unit litre,

author: b_force
author_rank: Super Contributor
timestamp: September 02, 2016, 12:04:09 pm
content: Ok, well the only thing I can remember is all the red correction marks in reports when I was studying

author: Galenbo
author_rank: Super Contributor
timestamp: September 04, 2016, 11:17:01 am
content: Quote from: b_force on September 02, 2016, 10:36:05 amthere's a whole proliferation around SI. There's base SI, derivated SI, accepted SI, each preference of course dependent of local/personal preferences.

author: Brumby
author_rank: Unknown
timestamp: September 04, 2016, 12:35:36 pm
content: ... and then you have the local flavours - such as: Two sandwiches short of a picnic.

author: mtdoc
author_rank: Super Contributor
timestamp: September 04, 2016, 02:41:49 pm
content: Shorter than a bee's dick.....Is that in thous or mills?

author: TimFox
author_rank: Super Contributor
timestamp: September 04, 2016, 05:04:35 pm
content: Quote from: Cerebus on September 02, 2016, 11:53:16 amI was taught that liters were retained to use the old definition (1 gram = 1 ml of water at maximum density) for chemistry purposes, which is not exactly 1 ml = 1 cm^3.

author: Zero999
author_rank: Super Contributor
timestamp: September 05, 2016, 07:56:21 am
content: Mass is an odd SI measurement because it has kg as the base unit rather than g. It's the only SI unit with a prefix on the base unit.

author: Galenbo
author_rank: Super Contributor
timestamp: September 05, 2016, 11:21:47 am
content: Quote from: Hero999 on September 05, 2016, 07:56:21 amIndeed strange. and Mg is never used, people express it Tonnes here.The should better redefine 1 newgram is the old 1 kg.

author: Nuzzler
author_rank: Contributor
timestamp: September 05, 2016, 11:34:19 am
content: I feel like there should be an option to vote for "both" or "either". It would be nice to have just one system, but I've worked with the two for long enough that it doesn't really bother me much that there's two. Metric for the cars, inches for the woodworking, inches around the house, metric for cycling, metric for measuring misc small things, inches for measuring misc big things.- Nuzz

author: b_force
author_rank: Super Contributor
timestamp: September 05, 2016, 12:38:32 pm
content: Quote from: Galenbo on September 05, 2016, 11:21:47 amIt's not odd, just read the history about it and it's understandable.What people "normally" use, is mostly not according SI standards.In official reports and stuff you need to use things like 10^-3 kg or 10^6 kg etcJust in speech it's a bit annoying, so that's why people use mili, Mega etc.

author: KeepItSimpleStupid
author_rank: Regular Contributor
timestamp: September 17, 2016, 07:13:41 pm
content: My boss said numbers should be between 1 and 10. So, a 10k resistor is a nice thing.Pascals are absurd.PCB dimensions in mm is tough to visualize. e.g. 300 mm x 200 mm. I don't have a sense yet.Similarly mph is a smaller number than km/hPipe and tubing is another world. A 7/8 inch elbow bought in a HVAC store is a 3/4" plumbing fitting. 1/4 Refrigeration tubing is different than 1/4" tubing.The English/metric mix in a car was weird. I needed a metric swivel socket and I did not realize that 5/32 was close enough.I really like to use my feet and knuckle to thumb distance to estimate feet and inches.Machining is weird with everything in thousandths. The tables posted on the wall help with conversions.The tire thing is weird. Disk drives used to have English and Metric mounting systems.When measuring stuff, I'll sometimes see what the metrc dimension is and the English dimension is and use whatever is more convienient.Lumber is fractional all the way and I don;t like it. I'd much rather 1/10 of an inch, I think. Who ever thought of 1/128 of an inch?I have no real problem with the metric system in the sciences, but I prefer gallons of gas.Cooking is just as weird with teaspons, tablespoons, oz, cups and pints. It gets kinda nuts when mixing lawn chemicals.Food is labeled in both units in the US. Some containers have metricied and some haven't. Milk is sold by the pint, quart, 1/2 gallon and gallon.I really hated to have to buy two sets of tools. The metric adjustable wrench comes to mind.

author: Zero999
author_rank: Super Contributor
timestamp: September 17, 2016, 07:52:23 pm
content: Oddly I'm more familiar with metric units for some things and imperial for others. I think about the weight of people in stone (multiples of 14lb or 6.36kg), yet when I'm baking a cake, I weigh the ingredients in grammes. I measure my waist in inches, yet when I design a case, I use mm.

author: Cerebus
author_rank: Super Contributor
timestamp: September 17, 2016, 08:00:20 pm
content: Quote from: KeepItSimpleStupid on September 17, 2016, 07:13:41 pmImmediately to my mind that's about the size of a sheet of A4 paper or, if you prefer, a copy of most magazines - in fact it's 3mm longer and 10 mm narrower.I often find myself judging PCB sizes by how they differ from standard eurocard sizes like 100mm x 160mm and 200mm x 160mm as those are often the sizes one has around for prototyping.

author: Simon
author_rank: Unknown
timestamp: September 18, 2016, 06:32:13 pm
content: Quote from: Halcyon on August 26, 2016, 02:11:02 amI noticed that too.I tend to use inches like the romans did, as an estimating measure. inches and feet are good for describing something you can't measure. If I can measure it I use metres and mm.