Help with imperial measurements

[Screwdriver]

This is perspective, Europeans know how long a meter is.

My architect can look at something and say that's X long and be with in 5mm this could be an 8m run.

What you are saying only holds for the generation that grew up with imperial measurements.

I know intuitively what 25,40,60,80kg feels like there for a I can extrapolate what the weights in the middle would feel like.
I would want to add many weights up when the base is 13

I appreciate that but it's not what I am trying to articulate. Having spent most of my life in the 20th century, I am too heavily invested in MPH to easily change my perspective but it is perspective that imperial excels in. Even that elusive parameter "time" is largely a base 60 system, one mile-a-minute being one mile-an-hour. They co-evolved as "human scale" measurements for all of our time/distance metrics and without dragging spacetime into the argument, they are two sides of the same coin.

More importantly, each unit is compartmentalised into its own reference frame. If I am casually discussing an item on the table my reference frame is inches, the coordinate system for the room might be feet, yards in the garden (or back yard...). If something is "miles away" the hyperbole is understood to take you out of the nearby into the far.

That subtle shift in spatial awareness simply due to the choice of unit should not be dismissed so easily. Thank goodness those crazy Europeans didn't insist on metric time! A day obviously relates to the spin rate of the earth, hours and minutes, though merely an invention, were chosen (and became generally accepted) because they fit comfortably into the human psyche.

In this modern technology era, we need to break time and distance down to literally unfathomable (!) units of measurements; nanoseconds and nanometers, light years and geological millennia. They can be understood scientifically but not empathically. I can distinctly remember how overwhelming it was when the compact disk arrived with the extraordinary capacity of 650Mb. How many books is that?

We are now in an era where everyday phenomena has become too abstract to easily fit into human comprehension so those duties are passed on to a computer to "understand it" for us. The metric system does a great job of bridging across exponentially larger scales but is less good at compartmentalising metrology to human scales of comprehension. Inevitably I suppose given the extreme precision we need to fuel the technology revolution but it would be a shame to throw away the more comfortable, if less useful, human scale imperial units.

It would be a shame because then we would be less inclined to do the math, exercise our brain and simply pass off the understanding to a robot to do for us.

 

[Kayos]

I appreciate that but it's not what I am trying to articulate. Having spent most of my life in the 20th century, I am too heavily invested in MPH to easily change my perspective but it is perspective that imperial excels in. Even that elusive parameter "time" is largely a base 60 system, one mile-a-minute being one mile-an-hour. They co-evolved as "human scale" measurements for all of our time/distance metrics and without dragging spacetime into the argument, they are two sides of the same coin.

More importantly, each unit is compartmentalised into its own reference frame. If I am casually discussing an item on the table my reference frame is inches, the coordinate system for the room might be feet, yards in the garden (or back yard...). If something is "miles away" the hyperbole is understood to take you out of the nearby into the far.

That subtle shift in spatial awareness simply due to the choice of unit should not be dismissed so easily. Thank goodness those crazy Europeans didn't insist on metric time! A day obviously relates to the spin rate of the earth, hours and minutes, though merely an invention, were chosen (and became generally accepted) because they fit comfortably into the human psyche.

In this modern technology era, we need to break time and distance down to literally unfathomable (!) units of measurements; nanoseconds and nanometers, light years and geological millennia. They can be understood scientifically but not empathically. I can distinctly remember how overwhelming it was when the compact disk arrived with the extraordinary capacity of 650Mb. How many books is that?

We are now in an era where everyday phenomena has become too abstract to easily fit into human comprehension so those duties are passed on to a computer to "understand it" for us. The metric system does a great job of bridging across exponentially larger scales but is less good at compartmentalising metrology to human scales of comprehension. Inevitably I suppose given the extreme precision we need to fuel the technology revolution but it would be a shame to throw away the more comfortable, if less useful, human scale imperial units.

It would be a shame because then we would be less inclined to do the math, exercise our brain and simply pass off the understanding to a robot to do for us.

The original link was posted as a bit of fun, as it amuses me that an archaic system is still widely used in allegedly civilised countries

You need to chill out a bit, my son is 10, very very clever, he will do well in life. However he has no idea what an inch or a pound is, and he has no need to know either

 

[Screwdriver]

The original link was posted as a bit of fun, as it amuses me that an archaic system is still widely used in allegedly civilised countries

You need to chill out a bit, my son is 10, very very clever, he will do well in life. However he has no idea what an inch or a pound is, and he has no need to know either

That's the first time I have seen that link!

I think it's funny when Curtis from CEE refers to anything other than metric as bananas. I'm all metric here....

 

[pressbrake1]

The one which truly pees me off is decimal inch, or whatever its name.

Micrometers, lathes, dro, milling machines are in decimals.
It’s fractions that drains my loins

 

[pressbrake1]

So if you were tiling a plane in mm (or decking out a boat) you'd probably round it off to the nearest mm.
I refer the honourable gentleman to the reply I made some moments ago.

As for "naming" a component identical to many others but with the wiggle room required to fit, does anybody else follow RRBuildings on Youtube? He makes very impressive post frame buildings.

Nothing is ever perfect so they might want an eight foot post with a 4 inch rebate and (typically) +1/8" to level to the not quite perfect concrete. He shouts down to the chap by the saw, "add an eighth to that one and just shy of a sixteenth to the other" etc. That's a human sized unit with its own name rather than a series of numbers.

Sounds about the same as "add 3mm to one and just shy of 2mm to the other one" but in the real world, thats more like a list of numbers than the name of a thing. The "thing" is mm and the measurement is just the number of those things. I don't want to overegg it but there is definitely a place for human friendly imperial measurements which can be more easily remembered or spoken than constant lists of numbers.

I think the problem is that the world never really made a firm commitment to wipe out imperial and go all in for metric. Sheets are still 8x4 (or 2440x1220), lumber is still 4x2 or a 6x2 and that is true even if they sell you a 100x50 or a 150x50. If I was on site and asked a lad to fetch me "three four by twos and two six by twos" I might be more confident than asking for "three hundred by fifty and two hundred by one fifty's". Even writing it down is a chore but the chore is the same when the numbers are spoken....

The pita is imperial wood sheets and metric plasterboard

 

[pressbrake1]

How do you mark out to 0.05mm when the tip of even an ultra-fine line marker is twice that thickness?

A scribe line when viewed and measured on my jig bore microscope is about 5thou so you have to line up with the correct side of the mark like you would using a sharpie.
So manually marking out with a rule and claiming 2 thou is bull

 

[merryman]

It isn't a bit of fun though. The use of different measuring systems is similar to the use of different languages and those who say everyone should speak my language is guilty of cultural Imperialism. I was brought up during the slow, and probably never will be completed, change to metric in the UK. I mostly think in imperial and change metric measurements to imperial in my head, this makes it far easier for me to read imperial drawings etc, than metric ones. Someone brought up with metric measurements will be doing the opposite, so finds imperial more difficult, but to say Americans shouldn't use any measurement system they like is, as I wrote above, cultural Imperialism, (no pun intended).

 

[Munkul]

I can quite happily measure, and mark out to +/- 0.05mm with a rule and even a tape - much to quite a few others surprise.

No you can't. You can't even measure your scribe lines that accurately. A vernier caliper doesn't even measure past 0.1mm. So how on earth do you know that you can mark out to that tolerance?

I'll go ahead and offer that I can aim for 0.5mm accuracy and hit +/- 0.25mm tolerance (ie half a mill) but again, I'm not really measuring the accuracy of my own markings. Most of the time it's all +/- 1mm anyway, if it needs precision the marking blue comes out.

 

[Screwdriver]

It isn't a bit of fun though. The use of different measuring systems is similar to the use of different languages and those who say everyone should speak my language is guilty of cultural Imperialism.

Oh I think it is. it is a shame that "imperial" has connotations regarding the British Empire but those pioneers of the industrial revolution which kick started this age of technology chose a measurement system, persuaded the world to follow and just got on with it. No one is saying "everyone should speak my language". At the time, if you wanted to join the party and share in the advancements that were being made, you kinda had to speak the same language.

So really, I just think it would be a shame to throw away all of the human sized imperial units for the reasons stated above. I mean who wants to drink a litre of beer (put your hand down @pressbrake1) or take a wrong turn and end up a kilometer off? It's just such an awkward word and while "click" is better it doesn't convey the deliberate vagueness of "a mile off" or "miles out". The metric unit is designed to be precise!

As for going wrong right at the start (I blame the ancient Babylonians) there are other examples where humanity has picked a wrong 'un. Benjamin Franklin guessed wrong about the flow of electrons so now every text book has arcane "holes" and positives are the absence of a thing. For a visuospatial learner, that's a real chore, all batteries are upside down..

Pi is another one. Show me where nature creates a diameter. Thats is an emergent geometric feature, derived from a radius which is the fundamental action in nature which causes diameters and circularity. Pick a pivot point and a stick et voila, there's your circles and diameters. Pi really ought to be the ratio of a radius to the circumference, instead we end up with zillions of "2's" where there ought to be none.

 

[Munkul]

My digital caliper measures to 0.01mm. Not that it is necessarily an accurate measure, as all measurements will have a systematic error at both starting and finishing points.

Just had a look at my vernier and it's graduated to 0.02mm, not 0.1, so part of my point was invalid anyway I think I'm thinking of my back marking gauge which is only to 0.1, and rightly so, as it's for marking plates etc for structural steel.

The other part of my point was, when interpolating by eye it's tricky enough to do it to 0.0X mm on a vernier scale. ie 0.05 isn't even marked on my scale, it's 0.04 or 0.06, and good luck falling between those two with any kind of repeatability.
How you'd mark from that, and then measure your marks, to that level of accuracy... that takes some laser eyes with 40/40 vision. Just not possible.
And CERTAINLY not possible with rulers/tapes.

 

[Maker]

Pick a pivot point and a stick et voila, there's your circles and diameters. Pi really ought to be the ratio of a radius to the circumference, instead we end up with zillions of "2's" where there ought to be none.

If you don't like Pi you can use Tau, equal to 2*Pi. Yes it tidies the circumference equation a bit but it uglies up the area equation, introducing a factor of a half. I'd say for every equation you can come up with containing 2*Pi, where tau would fit neatly, I could (Although I won't) find two more which use a single Pi, or 4*Pi, or Pi/n, or Pi^n, where using tau would make either no difference or an even bigger mess. Plus, it's easy to measure a diameter, usually not so easy to directly measure radius, so Pi is actually more useful for finding a circumference anyway.

 

[bigegg]

Pi is another one. Show me where nature creates a diameter. Thats is an emergent geometric feature, derived from a radius which is the fundamental action in nature which causes diameters and circularity. Pick a pivot point and a stick et voila, there's your circles and diameters. Pi really ought to be the ratio of a radius to the circumference, instead we end up with zillions of "2's" where there ought to be none.

It makes more sense when talking about area, though.
If pi had been c/r, then the area of the circle would have been ¼πr² - and various other formulae would have been even worse.

 

[Munkul]

I've just read one of the arguments for replacing Pi with Tau and I'm thinking to myself, all you have to do is double Pi I use circle equations quite a lot, but for area and circumference, so you're either doubling one, or halving the other... no difference!

 

[Screwdriver]

I've just read one of the arguments for replacing Pi with Tau and I'm thinking to myself, all you have to do is double Pi I use circle equations quite a lot, but for area and circumference, so you're either doubling one, or halving the other... no difference!

IKR but it was just an example of a deliberate choice for the definition of a parameter based on the technology of the time. Logically the fundamental value should be derived from the radius even if practically it is "easier" to measure diameter. When you do that of course you have to assume constant radius and equidistance from the focus...

In the same vein you might have thought someone would argue if you're going to go all metric, we need to get rid of the ancient Babylonian time base. If you did think that, you'd be right!

Count your fingers for the hours of the day, toes at night. Not so sure about a 10 day week though!

Clickspring would have a fit if they had to remake the Antikythera mechanism.

 

[bigegg]

I've just read one of the arguments for replacing Pi with Tau and I'm thinking to myself, all you have to do is double Pi I use circle equations quite a lot, but for area and circumference, so you're either doubling one, or halving the other... no difference!

On consideration, the equation:

e^πi+1=0

Isnt as ??????[1] with tau.


[1] head brain word list thing gone bye-bye.
Satisfying? Complete? Perfect?

 

[pressbrake1]

This is perspective, Europeans know how long a meter is.

My architect can look at something and say that's X long and be with in 5mm this could be an 8m run.

What you are saying only holds for the generation that grew up with imperial measurements.

I know intuitively what 25,40,60,80kg feels like, there for a I can extrapolate what the weights in the middle would feel like.
I wouldn't want to add many weights up when the base is 14

You couldn’t pick up 80kg with a jack!

 

[bigegg]

In the same vein you might have thought someone would argue if you're going to go all metric, we need to get rid of the ancient Babylonian time base. If you did think that, you'd be right!

Count your fingers for the hours of the day, toes at night. Not so sure about a 10 day week though!

Clickspring would have a fit if they had to remake the Antikythera mechanism.

The thing I always found fascinating is that the Babylonians split the circle into 360° of 60arc-minutes - which is one nautical mile at the equator, but is exactly equal to a regular mile somewhere around the latitude of Babylon...
Which means that presumably, they knew the world was a sphere(ish) shape.

 

[Maker]

On consideration, the equation:

e^πi+1=0

Isnt as ??????[1] with tau.


[1] head brain word list thing gone bye-bye.
Satisfying? Complete? Perfect?

Actually Euler's identity would still work with tau if you change it to a -1.

 

[Screwdriver]

On consideration, the equation:

e^πi+1=0

Isnt as ??????[1] with tau.


[1] head brain word list thing gone bye-bye.
Satisfying? Complete? Perfect?

You probably don't want to be messing about with log and exponents. Since the true Pi is twice faux Pi, you can get rid of that nasty -1 for a truly beautiful equation.

 

[Screwdriver]

Snap. Though I refer to the unity version where e to the i Tau is one.

<edit> while I am aware of some of the deeper mathematical issues, having been through that mill years ago, I have to Google it to err, double check of course. Otherwise it's all Greek to me...