Its not the unit itself, but how the unit relates to their larger and smaller counterparts that makes one system easier to work with than the other. Remembering 1000 meters to a kilometer and 1000 millimeters or 100 centimeters to a meter is easy. Remembering 12 inches to a foot and 5280 feet to a mile is harder. Having everything be multiplied/divided by 10/100/1000 also means units can be converted just by moving the decimal place, something you can do as mental math easily and quickly. Quick, without a calculator and without paper tell me how many feet are in two miles, now tell me how many meters are in two kilometers. Another problem with feet and inches is that there isnt anything smaller than them. Metric has millimeters, and if you need even smaller than that theres micrometers and nanometers, which follow the same 1/1000th progression that other metric units do. With inches, if you wanna talk small stuff you have to use fractions, and fractions are tedious and unintuitive to do math on.
Youre still allowed to divide up a meter into fractions if it makes your math easier, my point with inches and fractions was that there is no way to describe something smaller than an inch with a simple integer number, there are no nano-inches, and if there were, they would probably be a new entirely arbitrary fraction of an inch.
Youre still allowed to divide up a meter into fractions if it makes your math easier, my point with inches and fractions was
I mean technically true, but I get the sense metric users aren't trained to use fractions. Do European carpenters use fractions, or fuck around with 7 significant figures?
1/2 = 0.5 1/3 = 0.333... just multiply them together. Pick as much or as little accuracy as you want, 5 x 33 / 10 gives you about how many cm you need. If you need a tighter tolerance, 5 x 333 / 10 is how many mm you need.
Silly Americans would have to learn how to multiply in their heads and how to turn fractions into decimals, but otherwise they could divide lengths in their heads just like everyone else on the planet.
A blade is usually 3.175 mm (1/8" in imperial), you can't subtract a multiple of that, then easily divide the result by 2 or 3 over and over without getting increasingly nasty decimals or losing precision.
Cutting a 100 cm board in half isn't 100/2, it's (100-.3175)/2
If you need to actually divide a board into sixths just do like every other carpenter and mark off lines and cut to the right of the line and not on it exactly. Your last board is short, but they always are whether you marked it off in inches or cm. Take a look at a job sites garbage bin when they're framing, there are tons of ends of boards that routinely get tossed because they couldnt get it exactly right OR they shim the shit out of the last board, lol. They definitely dont divide the board into sixths perfectly including the fact that the width of the blade is going to shave off about 330 mm or about an 1/8th inch
Yes, the fractions are exact, but when you need to measure something, you probably won’t have anything marked for 48ths or whatever arbitrary fraction. You still have to make an approximation to use the closest fraction available.
For the seven digit numbers you’re using, the loss of precision is less than one part in a million, which shouldn’t be an issue for cutting planks of wood.
Also, there’s nothing about the metric system that stops you from using fractions.
you probably won’t have anything marked for 48ths or whatever arbitrary fraction
except the fractions aren't just random, that's the nice thing about it being divisible by 12, almost all of the time you do have those markers, so yes, you do have 48ths
In this example we're talking about inches and an inch is not any more divisible by 12 than a centimeter. Generally you're not going to see 48 divisions crammed into an inch on a ruler. You can have a set of specialty yardsticks with divisions set up for dividing by 3, 5, 7 etc. but you could do that with a meter the same way.
The argument was that imperial was better because you could do an exact division and get 6 and 25/48".
25 48ths is 33.333 repeating 64ths. You still have to eyeball a third of a division, the same way you would have had to eyeball half a millimeter.
Its not the unit itself, but how the unit relates to their larger and smaller counterparts that makes one system easier to work with than the other. Remembering 1000 meters to a kilometer and 1000 millimeters or 100 centimeters to a meter is easy. Remembering 12 inches to a foot and 5280 feet to a mile is harder. Having everything be multiplied/divided by 10/100/1000 also means units can be converted just by moving the decimal place, something you can do as mental math easily and quickly. Quick, without a calculator and without paper tell me how many feet are in two miles, now tell me how many meters are in two kilometers. Another problem with feet and inches is that there isnt anything smaller than them. Metric has millimeters, and if you need even smaller than that theres micrometers and nanometers, which follow the same 1/1000th progression that other metric units do. With inches, if you wanna talk small stuff you have to use fractions, and fractions are tedious and unintuitive to do math on.
Quick, without a calculator tell me, if you have a 1m plank and cut it into half, then cut one half into thirds, and tell me how long each piece is.
In metric that's (1m-.125)/2, which a calculator tells me is 499.9375. Chop that into thirds and a calculator tells me it's 166.5625
In imperial (40"-1/8")/2 is 19 and 15/16", chopping that into thirds, 19 and 15/16"-3/8"= 19 and 9/16", and divide by 3 and you get 6 and 25/48".
No messy decimals, no loss of precision.
Fractions, and if you need something smaller than 1/256, there's thou.
Youre still allowed to divide up a meter into fractions if it makes your math easier, my point with inches and fractions was that there is no way to describe something smaller than an inch with a simple integer number, there are no nano-inches, and if there were, they would probably be a new entirely arbitrary fraction of an inch.
I mean technically true, but I get the sense metric users aren't trained to use fractions. Do European carpenters use fractions, or fuck around with 7 significant figures?
Europeans know how to do fractions and use them except we don’t need to apply it to measurements because our system isn’t bad lol
wrong
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Trust me yank, if you use metric your whole life it’s easier than imperial
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i mean north american machinists use thousands of an inch or (0.001") which is in the same realm as a micrometer
1/2 = 0.5 1/3 = 0.333... just multiply them together. Pick as much or as little accuracy as you want, 5 x 33 / 10 gives you about how many cm you need. If you need a tighter tolerance, 5 x 333 / 10 is how many mm you need.
Silly Americans would have to learn how to multiply in their heads and how to turn fractions into decimals, but otherwise they could divide lengths in their heads just like everyone else on the planet.
A blade is usually 3.175 mm (1/8" in imperial), you can't subtract a multiple of that, then easily divide the result by 2 or 3 over and over without getting increasingly nasty decimals or losing precision.
Cutting a 100 cm board in half isn't 100/2, it's (100-.3175)/2
If you need to actually divide a board into sixths just do like every other carpenter and mark off lines and cut to the right of the line and not on it exactly. Your last board is short, but they always are whether you marked it off in inches or cm. Take a look at a job sites garbage bin when they're framing, there are tons of ends of boards that routinely get tossed because they couldnt get it exactly right OR they shim the shit out of the last board, lol. They definitely dont divide the board into sixths perfectly including the fact that the width of the blade is going to shave off about 330 mm or about an 1/8th inch
Yes, the fractions are exact, but when you need to measure something, you probably won’t have anything marked for 48ths or whatever arbitrary fraction. You still have to make an approximation to use the closest fraction available.
For the seven digit numbers you’re using, the loss of precision is less than one part in a million, which shouldn’t be an issue for cutting planks of wood.
Also, there’s nothing about the metric system that stops you from using fractions.
except the fractions aren't just random, that's the nice thing about it being divisible by 12, almost all of the time you do have those markers, so yes, you do have 48ths
In this example we're talking about inches and an inch is not any more divisible by 12 than a centimeter. Generally you're not going to see 48 divisions crammed into an inch on a ruler. You can have a set of specialty yardsticks with divisions set up for dividing by 3, 5, 7 etc. but you could do that with a meter the same way.
Except I have several tape measures with 64ths, they aren't exactly uncommon and you can do 48ths with 64ths
The argument was that imperial was better because you could do an exact division and get 6 and 25/48".
25 48ths is 33.333 repeating 64ths. You still have to eyeball a third of a division, the same way you would have had to eyeball half a millimeter.
you don't have to eyeball it as much though
:oh-shit:
those both seem confusing