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why is the US not Metric
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tooki:

--- Quote from: Cerebus on November 16, 2019, 12:19:22 pm ---
--- Quote from: KL27x on November 16, 2019, 07:36:32 am ---I think half of the metric fans think that US converting to metric will mean they don't need to buy SAE wrenches anymore. And even if American did, that will not happen.

--- End quote ---

What makes you think that anyone outside the US (and possibly Canada, eh!) buys SAE sized tools? Every single tool I've bought since about 1981 has been metric sized. I say 1981 because I remember having to get some secondhand imperial sized tools back then to maintain an antediluvian AJS motorcycle that some of us were restoring.

--- End quote ---
Well, for sure they’re not something you find at the local DIY shop, but for industrial settings, they are sold. For sure, classic car mechanics need them, and I guess some industrial machinery has them. Here in Switzerland, the big industrial tool supplier carries a surprisingly comprehensive selection of US customary tools, and a small selection of fasteners. PB Swiss, the big Swiss screwdriver maker, makes US customary hex keys and stuff, too.
Zero999:

--- Quote from: CatalinaWOW on November 16, 2019, 04:43:40 am ---It's hard to complain about someone not joining the modern world while refusing to use a smartphone or other device to access the intelligence of the world.

--- End quote ---
A smartphone is no good when you're covered in oil and grease or wet.


--- Quote from: forrestc on November 16, 2019, 02:12:02 am ---
--- Quote ---4'6" x 18" x 12" in gallons

--- End quote ---

Results in the following result:


--- Quote ---(4 ' 6 ") x (18 ") x (12 ") =
50.4935065 US gallons

--- End quote ---

Doesn't get much easier than that   :)

--- End quote ---
Nice, but that gives me the result in imperial 42.044622. It must be because I'm in the UK. I have to specify US gallons and you've forgotten the weight part of my calculation.


--- Quote from: vk6zgo on November 16, 2019, 01:11:32 am ---I haven't a clue what the conversion factor between cu ft & US Gallons is.
If I knew that, the whole thing would be done with two calculations. (with the values given, converting to decimal feet is obvious)
--- End quote ---
That's the problem and what about the part where I converted to pounds? With imperial, I'd have to look it up, but I can remember the conversion from kg to lb.


--- Quote from: KL27x on November 15, 2019, 10:43:42 pm ---Wow, freedom gallons. So many metric trolls. I think the metric trolls added up in this thread convert to 4.6 rstophers, imperial unit of troll. Conversion is 1 rstopher: 1.108 bsfeechannel.

Zero, you could also do the calculation in imperial all the way to cubic feet, then convert to cubic decimeters. Then convert L to gallons. At least if you do in cubic feet, you have that original parameter of 1 foot high vs 308.4mm. You do just ONE conversion to get Liters. You don't have to do extra conversion of all dimensions of the tank to metric, doing 3 extra steps vs 1.

The reason you convert all distances to metric is maybe you are more comfortable to think in metric? Americans think in imperial. That's your internal calibration, and it is probably not going to ever change. Same can be said about americans. We know what is 1.5m, but we don't intrinsically know if that is Tom Cruise or James Harden height. (Ok, I know it's way closer to Tom Cruise. But Tom Cruise or Kevin Hart? Getting tougher..)

When performing a calculation like your example, anyway you do it should be equally comfortable. I don't get unit loyalty.

--- End quote ---
The reason why I find the calculation easy is because I can remember all the conversions from metric to most common imperial/customary units. I'm not familiar with the conversion from cubic feet to litres.


--- Quote from: KL27x on November 16, 2019, 12:53:57 am ---Zero, I calculate for you. The cube root distance of a gallon is 6.136 inches. So a (freedom) gallon is a cube 6.136" per side, or 0.5113 feet, or 155.9mm.

This may be easier to use than mL:pint.

Of course when the numbers get so big or small they are not really relate-able, engineers commonly use cubic feet, or cubic meters or other stuff that is not a liter or a gallon.

--- End quote ---
Yes, I could have used dm, rather than cm to avoid the large numbers in the first place, but it's not a common unit, as cm, so I didn't think of it. The beauty of metric is, just shift the decimal place when numbers just get too big/small.


--- Quote from: KL27x on November 16, 2019, 07:36:32 am ---^ I think Catalina WOW is referring to another superfan of metric when he said that. The one from UK. Another country that changed from imperial to metric in recent history.

Maybe you guys are jealous that America still uses imperial and no one other than you guys care, lol.
--- End quote ---
What me? As I've already said, I couldn't give two hoots whether the US uses metric or not. It doesn't bother me. I'm just stating the fact that metric is easier, because the system is designed from the ground up, rather than imperial which has evolved organically. Although I was born long after the UK adopted metric, I have used imperial/customary quite a bit. I've worked for Lockheed Martin in the past and my current employer works on US projects, so I've had a decent exposure to the archaic imperial system and am well aware of how much of a PITA it is.

Interestingly my father, who was born just after the war in 1945, was studying at university, as a mature student at the time when the UK was going metric, in the mid 1970s. He was given the choice of taking the exams in either metric or imperial and chose metric, even though he had only used imperial for the first 25 or so years of his life. Although he could easily visualise imperial units such as lb/iin2, he chose SI because he could see how it makes calculations much easier.

Here's another calculation to illustrate the point: a 400V 3 phase geared motor is 80% efficient. It lifts a 500lb weight,  to a height of 12ft, in 30 seconds. Think about how you'd work out the power in metric (Watts) vs imperial (horsepower). Now calculate the current draw, assuming a power factor of 0.9. I'm not going to go through it, but to calculate the current you'll need power in Watts, a metric unit, so why not start with metric units in the first place?  Try again with 227kg and 365.8m. See how much easier it is.
KL27x:
America:
We know metric is better


--- Quote ---Here's another calculation to illustrate the point: a 400V 3 phase geared motor is 80% efficient. It lifts a 500lb weight,  to a height of 12ft, in 30 seconds. Think about how you'd work out the power in metric (Watts) vs imperial (horsepower). Now calculate the current draw, assuming a power factor of 0.9. I'm not going to go through it, but to calculate the current you'll need power in Watts, a metric unit, so why not start with metric units in the first place?  Try again with 227kg and 365.8m. See how much easier it is.
--- End quote ---

You know, America has heard of this thing called the watt. This is what we use for this for electronics. I'm sure your countries still use horsepower or CV to describe car engine power. So maybe you should tell yourself this.

The biggest problem for America is that if America ever (officially) changes to metric (not like it isn't already metric), there will be only 5000 Rowandans for us to feel smug and superior over. You guys seems to be really enjoying this (by giving so many examples that don't apply to us or to you or to 99% of average citizens).

Tooki:

--- Quote ---What makes you think that anyone outside the US (and possibly Canada, eh!) buys SAE sized tools? Every single tool I've bought since about 1981 has been metric sized. I say 1981 because I remember having to get some secondhand imperial sized tools back then to maintain an antediluvian AJS motorcycle that some of us were restoring.
--- End quote ---
I think all the people who complain about fastener sizes on this thread have had to do so at some point. Even you admit you haven't bought them because... you already own a set. :) I don't think this is going to change even if America were to change its road signs and speedometers and drivers licenses and for us to sell houses in square meters and for cops to call out APB on 20 yr old male, 1.68 meter, 70 kilo.

And I know you, Tooki, are not one of these guys. All of your posts are reasonable and practical. They know who they are. The ones making the imperial or dry gallon crack and such.

Re: fastener situation in America:
I'm not a mechanic or a machinist or a professional fabricator. When it comes to wrenches (spanners? I mean the bars of metal with the open end and the box end), I have only one set, and it is metric. I have lived here my entire life, and I have never purchased an SAE wrench. (Inexpensive sockets sets usually come with both, so that is all I have needed to date for SAE bolt, which is not common). This is all you need to work on most modern cars in the last 20 years (at least 20, which goes back before I started to do anything other than sit in class rooms and play computer games) as well as most power tools (that are pretty much 99.9999% imported).  But, I have only SAE set of hex bits. I find that the closest torx bit usually works for metric hex fasteners.*  And for some reason, I find hex screws are rather often SAE, even on imported tools. The metric hex fasteners is the odd duck in America, still, IMO. But that is just my single anecdote.

So Tooki, you are one up on me to even own a set of SAE wrenches. I have never.

*and if that doesn't work, a piece of hex bar and a belt sander will do the trick.
soldar:

--- Quote from: vk6zgo on November 16, 2019, 12:24:07 pm ---They are commonly known as "AF"(across flats).
...
Metric spanners are "across flats", too, but we don't call them "AF".
--- End quote ---


Originally spanners/wrenches were denominated with the size of the thread, not by the size of the head. Then they realized it made more sense to use the size of the head "across flats".

Kind of the same thing with pipes. Nominal 1/2" pipe thread has a diameter of 0.8125" because the denomination is not the measure of the thread but of the inside diameter of the standard pipe with that thread. These days pipes walls are thinner so in a 1/2" pipe nothing measures 1/2".
Zero999:

--- Quote from: KL27x on November 16, 2019, 06:46:06 pm ---America:
We know metric is better
--- End quote ---
I'm quite sure most well-educated Americans are aware of the superiority of metric, over imperial and customary, but there do seem to be those who won't have it and the same is true for those metric zealots who can't see why the US won't fully convert.

I fully understand why the US won't fully convert to metric, the same as why the UK still hasn't fully gone metric: the cost doesn't justify the benefit, despite what the metric evangelists might say.


--- Quote ---
--- Quote ---Here's another calculation to illustrate the point: a 400V 3 phase geared motor is 80% efficient. It lifts a 500lb weight,  to a height of 12ft, in 30 seconds. Think about how you'd work out the power in metric (Watts) vs imperial (horsepower). Now calculate the current draw, assuming a power factor of 0.9. I'm not going to go through it, but to calculate the current you'll need power in Watts, a metric unit, so why not start with metric units in the first place?  Try again with 227kg and 365.8m. See how much easier it is.
--- End quote ---
You know, America has heard of this thing called the watt. This is what we use for this for electronics. I'm sure your countries still use horsepower or CV to describe car engine power. So maybe you should tell yourself this.

The biggest problem for America is that if America ever (officially) changes to metric (not like it isn't already metric), there will be only 5000 Rowandans for us to feel smug and superior over. You guys seems to be really enjoying this (by giving so many examples that don't apply to us or to you or to 99% of average citizens).
--- End quote ---
Yes, I've heard people use horsepower for cars but kW is becoming more common and is exclusively used for legislative purposes: we have a law which restricts the maximum power output (Watts) andengine size (cm3) a young person can have in their motorcycle. It was introduced to stop youngsters buying monster bikes and getting themselves killed.

Granted, the examples I've given don't affect everyone, but they're both fairly common in the fields of engineering and construction. Forget converting between metric and imperial/customary, which was just a distraction. The point was, when working with SI units, one doesn't have to perform any conversions beyond moving the decimal place.
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