Is it Time to get Onboard with Metric Measurements?

[Neil K Walk]

I can't believe we're still having this debate after several decades of the US being stuck in self delusion. Change will not happen. Progress only happens in response to some pitfall. The pendulum will continue swing back and forth.

[HodgdonExtreme]

Originally Posted by robj144

As a side note, in both systems, they really need to start saying that people have a MASS and not a WEIGHT. Everyone should be saying, my mass is ___, not my weight is _____. And yes, I know scales are measuring weight, but the units scales output are units of mass in both systems. There's an inconsistency there.

This used to irk me a quite a bit as well, but I've gotten over it. For those of us that never leave planet Earth; weight and mass are effectively interchangeable. No, it's not "correct" - and gravity is a bit different everywhere on Earth - but for anything short of extremely rigorous scientifics - it just doesn't matter at all.

It is a bit amusing, though, that most Americans have no idea the "Slug" is the actual imperial unit for mass...

I also think it's amusing that some auto makers rate their torque output in kilogram-meters, I thought the twisting force of torque was supposed to be RxF - so we should be talking about forces, not masses. Metric system has such a nice and defined unit of force (newton), so why *******ize your torque specification by using a mass instead?? Still, it just doesn't make any practical difference.

[Nama Ensou]

Originally Posted by Neil K Walk

I can't believe we're still having this debate after several decades of the US being stuck in self delusion. Change will not happen. Progress only happens in response to some pitfall. The pendulum will continue swing back and forth.

Most people now have an assortment of both metric and standard wrenches, and even seem to have a grasp of what either one looks like when guessing which one is needed.

In other news, Rome will never fall, Constantinople's walls will never be breached and Neil Young will never stoop to playing electric.

[RP]

Originally Posted by robj144

...As a side note, in both systems, they really need to start saying that people have a MASS and not a WEIGHT. Everyone should be saying, my mass is ___, not my weight is _____.

Especially if you're on the moon???

[robj144]

Originally Posted by HodgdonExtreme

This used to irk me a quite a bit as well, but I've gotten over it. For those of us that never leave planet Earth; weight and mass are effectively interchangeable. No, it's not "correct" - and gravity is a bit different everywhere on Earth - but for anything short of extremely rigorous scientifics - it just doesn't matter at all.

It is a bit amusing, though, that most Americans have no idea the "Slug" is the actual imperial unit for mass...

I also think it's amusing that some auto makers rate their torque output in kilogram-meters, I thought the twisting force of torque was supposed to be RxF - so we should be talking about forces, not masses. Metric system has such a nice and defined unit of force (newton), so why *******ize your torque specification by using a mass instead?? Still, it just doesn't make any practical difference.

Never even knew some use kg-m as a unit of torque. It doesn't make sense and the conversion by multiplying by g makes no sense either.

Another weird thing about torque is that its "typical" SI units are N m. But a N m is a Joule in the context of work and energy. So, if you said torque is measured in Joules, it's not technically incorrect.

[robj144]

Originally Posted by RP

Especially if you're on the moon???

Almost... a scale is measuring a force and in many cases the amount of gravitational acceleration at any location is pretty well known. So, the scale could "calibrate" and divide by the gravitational acceleration and output your actual mass which would be the same on the moon.

However, the amount of gravitational acceleration does vary a bit, so it would be an approximation of your mass if one used a universal number at every location.

[loco gringo]

Originally Posted by RP

Especially if you're on the moon???

Especially if you are on the moon!

[Bob Womack]

Originally Posted by RP

Is that a real TD or a kit car? I ask because I'd never seen a TD with wire wheels although I've seen TFs with wire wheels...Either way, it's beautiful....

The red one appears to be based on a VW Beetle chassis.


Bob

[HodgdonExtreme]

Originally Posted by robj144

Never even knew some use kg-m as a unit of torque.

Originally Posted by robj144

Another weird thing about torque is that its "typical" SI units are N m. But a N m is a Joule in the context of work and energy. So, if you said torque is measured in Joules, it's not technically incorrect.

It *would* be technically incorrect. There is a very distinct difference between energy and torque: Energy is a scalar dot product of the force vector and the displacement vector, while the torque is a vector cross product of a force vector and a distance vector.

So, while units describing both energy and torque are the same - the mathematics behind how those units interact is different - making the results mean different things...

[robj144]

Originally Posted by HodgdonExtreme

It *would* be technically incorrect. There is a very distinct difference between energy and torque: Energy is a scalar dot product of the force vector and the displacement vector, while the torque is a vector cross product of a force vector and a distance vector.

So, while units describing both energy and torque are the same - the mathematics behind how those units interact is different - making the results mean different things...

Of course, but they are both kg (m/s)^2.

[hubcapsc]

I think it would be a disaster for the building trade.

A 4x8 sheet of plywood becomes 121.92 X 243.84 centimeters.

16 inch centers become 40.64 centimeter centers.

Change the size of dimensioned lumber and remodeling
becomes a nightmare.

-Mike

[RedJoker]

Originally Posted by hubcapsc

I think it would be a disaster for the building trade.

A 4x8 sheet of plywood becomes 121.92 X 243.84 centimeters.

16 inch centers become 40.64 centimeter centers.

Change the size of dimensioned lumber and remodeling
becomes a nightmare.

-Mike

I think it could work. You list cm to two decimal places. I've been around construction enough to know that those dimensions you listed aren't accurate to 0.004 inches.

[Talentless]

Originally Posted by hubcapsc

I think it would be a disaster for the building trade.

A 4x8 sheet of plywood becomes 121.92 X 243.84 centimeters.

16 inch centers become 40.64 centimeter centers.

Change the size of dimensioned lumber and remodeling
becomes a nightmare.

-Mike

Every country in the world is able to build structures using metric.

For general construction where there is a legacy imperial system most builders round off the measurements to the nearest mm.

In Australia, New Zealand etc where we changed over to metic 50 odd years ago it has been a significant problem.

Also, we need a new gripe thread... its Litre not liter, centimetre not centemeter and kilometre not kilometer.

As we are the users of metric and not the USAat this time, I claim the correct spelling rights to metric

I'm off to the basement to avoid the incoming.....

[Silly Moustache]

Originally Posted by hubcapsc

I think it would be a disaster for the building trade.

A 4x8 sheet of plywood becomes 121.92 X 243.84 centimeters.

16 inch centers become 40.64 centimeter centers.

Change the size of dimensioned lumber and remodeling
becomes a nightmare.

-Mike

All building materials have been metric for years!
a "2x4" has been a 50 x 100 for as long as I've been buying wood.

[HodgdonExtreme]

Not long ago, I was doing an alignment on my car - which is a tedious process that requires several iterations of careful measurements to get just right.

For the first couple iterations, I was using my regular tape measure. A 32nd of an inch is about 0.032", which isn't quite precise enough for the job. So you really need to be dealing with 64ths - which is about 0.016". It is really, really obnoxious to work with 64ths of an inch.

Anyway, when I got back to my alignment job the next day, I accidentally grabbed my buddies tape measure, ruled in metric. At first I was gonna go find my standard tape instead, but decided to give metric a go for the job. One mm is about 0.040", so a half millimeter is about 0.020", which is just about the right level of precision for the job... And way, way, way easier to manage than 64ths of an inch.

It made the job much less tedious.