I just watched the demo just uploaded to YouTube titled Shapr3d Holes. Fairly basic and uses metric.
As I watched the video I realized that the only way I could relate dynamically to lengths in mm was to translate back through English/Imperial as I had memorized 1” = 2.54 cm and I can relate to an inch and that a meter is about 10% longer than a yard. A mm to me is just something small although I now remember that 8mm is about a 30 caliber bullet (0.30”). Furthermore I relate that 1” is about the length of the tip of my thumb to its first joint, 1 foot is about the length of my foot and 1 yard is about the length of my arm.
So, I wondered if metrically raised children/people have similar bio comparisons? Or any type of comparisons to everyday common objects? Inquiring minds, you know?
I was adout 10 years old when the uk converted to the metric system.
The imperial system was the norm for daily use 4” x 2”, 12ft etc was how things were explained to us at school. Our money was based on 12 pennies to the shilling. 20 shillings the pound which gave us 240 pennies to the pound. At the time of the change over I was told that we were changing our money to match the American system. We now have 100 pennies in the pound in the same way that there are 100 cents to the dollar. It was the metric system. Everything was now in 10’s and I was very surprised that America use the imperial system when I first visited the states because I really believed we had the metric system from them.
My brain works in both. At work I use a lot of timber I visualise it in the imperial sizes 4”x2” etc. but measure it in mm when I am working with it. The decking is 145mm wide but when I am working on a rough count I will measure the width of the area to be decked in feet and double it to get the 6” board count. Support spacing is easy I don’t count I just use the red markers on my tape to give me the 16” centres or the metric equivalents.
If I am looking for a short length of timber from the off cut pile my eyes will search for a piece about 2 foot long then cut it to 600mm!
The same with sheet material. An 8’x4’ sheet of ply is 2440x1220mm, asked for and loaded into the truck in imperial worked on and fitted in metric. There is no need to convert because I work in both.
There is no right or wrong. It’s there on both edges of the tape measure I use.
The only difference I have noticed these days is there are a lot of kids working in builders merchants who look at me with that strange glazed look in their eyes when I am asking for 2” no 8 screws because the materials are no longer sold with that size description. And the older assistants seem to be getting fewer on the ground.
Thanks Paul for your unique story. I too have no problems working in metric, having lived 5 years in France. The problem is association in real time. In the video, lots of lengths age moving around.
I was looking more for a response from someone born and raised in the metric system. Did their mother say, a mm is the width of a worm? Etc.
Even more difficult is the difference in vehicle efficiency: miles/gallon vs liters/100 km.
In Australia we are experiencing the worst drought for 100 (metric haha) years. i live in a farming district. water measurement has slowly changed from points/inches to mls in the last 20 years. i’m a scientist so when people get rain and talk in points of rain i ask them how big is their house and say “oh so you got 2.5 cubic meters of rain overnight”. old farmers just don’t grok that conversion. silly i know but i can’t stand imperial units. USA i am looking at you. ps. while australia is metric since 1966 people migrated from saying how many miles between places and now say how many hours. not km.
One of the hardest concepts between the two systems is vehicle fuel economy. In the US, a car that gets 30 mpg (miles per gallon) is considered ok. But in Europe the expression is liters per 100 km. 8l / 100 km is about 30 mpg but has absolutely no meaning to an American. We’ll see how this eventually goes as the US becomes more metric.