American Customary (a.k.a Freedom) Units vs Imperial vs Metric

[Mr. Coffee]

My feeling is converting between units is kind of a pointless activity. What is more important is having a tactile sense of what those units are at scales we care about.

• A dime weighs about a gram. As does a good-sized insect.
• A hiker's water bottle full of water weighs a bit over a kilogram.
• You can walk a kilometer at a leisurely pace in about fifteen minutes. At a brisker pace it will take about ten minutes.
• Two normal steps are about a meter, depending on the length of your legs. Unless you are very tall and have very long legs a meter is an uncomfortably long step.
• Highway speeds are typically about 100km/h. Which makes estimating time easy: a 650 km drive will take something more than six and a half hours.
• A cyclist riding long distances tends to average between 18 and 20 km/hour.
• A strong hiker over non-insane terrain walks about 5 km/hour.
• 1 KWh is the equivalent of about 3 to 4 sticks of dynamite.
• Pi seconds is a billionth of a century.

 

[Jeremy McCreary]

My feeling is converting between units is kind of a pointless activity.

Not entirely. On EBR, I like to convert km to miles and kg to pounds in my head so our metric users can't trick me into thinking that they ride farther or faster or have lighter bikes than I do.
;^}

 

[Chargeride]

I hear Canadians measure distance in time.

 

[Stefan Mikes]

I hear Canadians measure distance in time.

No it is the American

 

[Roamers]

No it is the American

True. Everyplace we go locally is 15-20 minutes away.

 

[Stefan Mikes]

Not entirely. On EBR, I like to convert km to miles and kg to pounds in my head so our metric users can't trick me into thinking that they ride farther or faster or have lighter bikes than I do.
;^}

I tried 63 miles for Chargeride's 63rd birthday. It felt as long as his lifetime!

On the other hand, I'm pretty fond of miles. My InPost parcel locker is a mile away. My local grocery shop is two miles away. A coincidence?

My favourite riding distance is a 50-miler. If I've ridden for 70 miles, I'm proud!

 

[Stefan Mikes]

My feeling is converting between units is kind of a pointless activity. What is more important is having a tactile sense of what those units are at scales we care about.

• A dime weighs about a gram. As does a good-sized insect.

Heh, perhaps an American insect The biggest insect here, the hornet, weighs up to 0.6 gram.
For your reference, the Specialized SL Range Extender battery is 1.0 kg sharp

Did I already tell you 25.4 km makes a million inches? (I'm sure I did!)

 

[Chargeride]

I'll do it for you Stefan as long as your 21.

 

[Stefan Mikes]

I'll do it for you Stefan as long as your 21.

Just do 66 km next year, not in Turbo but on the flat

 

[Roamers]

We're great at directions also. Take a left where that monster Oak tree got blown down back in the 2018 storm.

 

[Jeremy McCreary]

Many occasions when the time to a place is much more important than the distance. For example, our nearest Trader Joe's is always 7 mi away, but the drive time can vary from 15 to 30 minutes depending on traffic.

Luckily, we have Google Maps to tell us the estimated drive time. If it's 30 minutes, I'll settle for Ralph's, which is a consistent 5 minutes from home but generally can't compete otherwise.

For places with consistent drive or ride times (or equivalently, average speeds), time is equivalent to distance. Hence the light-year as a unit of distance, as the speed of light in vacuum is the same constant for all observers.

 

[Chargeride]

Google maps has increased the use of time for distance.
When were driving somewhere with fiddly roads, I'll announce..only 7 miles, oh and 40 mins.

 

[Stefan Mikes]

Google maps has increased the use of time for distance.
When were driving somewhere with fiddly roads, I'll announce..only 7 miles, oh and 40 mins.

Once I was using a Polish satnav software called NaviExpert. I was to take a trip to a city perhaps 100 km away by expressway. NaviExpert estimated the time to some 4 hours. How come? The app knew there was a massive roadblock on the way and no chance for a detour...

 

[6zfshdb]

My 80 year old imperial brain takes too long to do conversions and I don't have enough years left to train it to think metrically.

 

[spokewrench]

My 80 year old imperial brain takes too long to do conversions

That's why I quit using inch tapes in the 1980s. I wanted a replace a rotted clapboard with one accurate to 1/32". Converting a line on the tape to a fraction was so distracting that I cut exactly 1" too short. Mm numbers are also easier to remember than inches and fractions.

A few years later, I told a neighbor that I preferred metric wrenches because they didn't need fractions. He said he hated metric wrenches and was good at the inch system. One day as he worked on his truck, his 9/16 wasn't quite big enough. He asked me what the next size was.

 

[Stefan Mikes]

his 9/16 wasn't quite big enough.

10/16? (Sorry, I don't know!)

A fun fact: M15 is not among standard car wrenches but, ironically, it is met on older bicycles with the wheel mounted to fork drops by a metric nut.

On last Saturday, my mate Krzysiek was to replace the inner tube in his vintage bike. I wanted to help him with any tools I had with me. No chance! He needed a 15 mm wrench (and it got stuck inside his frame storage). He didn't use Presta valves but Schrader. He had to be self-sufficient!

 

[Chargeride]

That's why I quit using inch tapes in the 1980s. I wanted a replace a rotted clapboard with one accurate to 1/32". Converting a line on the tape to a fraction was so distracting that I cut exactly 1" too short. Mm numbers are also easier to remember than inches and fractions.

A few years later, I told a neighbor that I preferred metric wrenches because they didn't need fractions. He said he hated metric wrenches and was good at the inch system. One day as he worked on his truck, his 9/16 wasn't quite big enough. He asked me what the next size was.

9/15?

 

[Roamers]

10/16?

Correct. 5/8"

 

[spokewrench]

10/16? (Sorry, I don't know!)

A fun fact: M15 is not among standard car wrenches but, ironically, it is met on older bicycles with the wheel mounted to fork drops by a metric nut.

On last Saturday, my mate Krzysiek was to replace the inner tube in his vintage bike. I wanted to help him with any tools I had with me. No chance! He needed a 15 mm wrench (and it got stuck inside his frame storage). He didn't use Presta valves but Schrader. He had to be self-sufficient!

In my wrench sets, M16 is the one they may skip. And M12. That's why I love 12-point. A loose fit can give a solid connection.

Torx seems to be the same. In one case, T20 worked fine to break screws loose. Then I discovered that they were T25.

 

[Stefan Mikes]

A typical metric car wrench set. The 15 mm bicycle wrench is not here. I also think I needed M18 for the nuts for the hub-drive motor.

I don't think Torx has any relation to Metric or American sizes.

I own this kit, just in case. I hardly ever need it.