Really though, the most ardent defence of USC units is fuelled by great amounts of Copium. The US Customary set of measurements is several independent systems of measurements which often radically different origins and sometimes irrational conversions, all stacked upon each other and dressed in a trench coat. For instance, the mile has Roman origins while the inch and foot were defined separately, much later, and with a lot of regional variation. The French foot was longer than the English foot, which is why Napoleon was listed as 5'2" tall while he was actually closer to 5'9", or 1.71 m, which was pretty average for the time.
Which one of these is more straightforward to calculate:
You are tasked with installing a rail along a 1 mile long bridge. You know you can use two half inch bolts to affix it every three feet. How many bolts do you need?
You are tasked with installing a rail along a 1,5 km long bridge. You know you can use two M12 bolts to affix it every metre. How many bolts do you need?
Conversions within dimensions in USC require you to memorise arbitrary conversion numbers. Conversions within dimensions in SI require you to move the comma a few spots.
Besides, if the US Customary system of units is so great, why did most of the world voluntarily switch to SI units?
This is exactly my experience. I've worked for four different manufacturing companies in the Midwest. Three of them were multi billion dollar companies. All four of those companies used metric almost exclusively.
Such a stupid misconception that is constantly reposted
start by putting metric units next to the SAE units in the labels
Eventually people get used to the units and then you phase out the use of them.
All science and most of the mechanical engineering is done in metric already. If you have a car made in the last 20 years ask the fasteners are already metric.
So it really isn't that hard..
Ford still uses SAE bolts/screws for door panels, but not always.I only keep metric sockets and wrenches in my box, but have to keep a 1/4" socket just for the random Ford I have to work on.
For anything construction-scale, all supplies sold in the US are based on 4x8' sheet goods and 16-24" on-center framing. I also concede that king George the 74th's foot length is more human-scale when dealing with large measurements: 20 feet vs 6096 mm. I still use metric when possible, however - I find it easier and more accurate.
For EVERYTHING else I've switched to using metric.
Context: I grew up in the US using imperial units and only pivoted to the metric system in 2020. If I grew up thinking in metric and building supplies/standards used it, it'd be superior in every way.
TL;DR I like my imperial/metric combo tape measure.
All plans use mm exclusively. Airport blueprints, for example, are in mm. At first blush it seems excessive, but it makes sense from a consistency & accuracy POV - 6.096m takes up 2 more characters than 6096 - they don't even need to specify the units "mm", because it is assumed, and anything else introduces room for error.
Divide a metre by 4 and you get 0.25 meters or 25cm
Dived a foot by 4 you get 3 inches.
Dived a yard by 4 you get 9inches
Metric here wins in my opinion.
Now let's go by 3
1m by 3 is yes 33.3r not great but 1m is 100cm and that's how it is.
1ft by 3 is 4 inches. Sure looks great now.
Except size resolution is far greater in metric in simple forms
Every inch is 2.54 cm obviously they dont round up nicely.
Once we have to go smaller than an inch we need 15/16s of a inch, smaller then a cm we drop down to mm.
10mm makes a cm.
In super practical terms i need a spanner, 16mm is to big, i get the 15 next.
5/8 is to big what do i get next?
(I know the answer)
Also another argument is well whats if you need half a mm etc we just use 0.5m or
0.7mm etc
Very small sizes for most everyone day to day.
Sure it's not great breaking it too 0.whatever, but metric does it so much smaller as imperial made that jump to incorporate a size smaller then an inch.
Division no is the problem in one unit, inch, feet, etc, because use fraccions instead of decimls, but the problem is the conversion from inch, feet to others (yards, miles), which is the source of a lot of errors, like those from the Mars probes or some catastrophigs breaks of bridges in the past, apart of some problems in physics, because using for weught and mass the same unit.
No, imperial are not human measures, never has been since humans count with 10 fingers.
I’m terrified of driving the day they move the US from miles to kilometers. People go well over the speed limit as it is. I can only imagine how many people would read the kilometer per hour speed limit as miles.
Human scale? Not yours or mines, measures of the ffoot, thumbs and random desires of a dead British King in the far past.
No problem in metrics, at least if I don't build a hut in the wood with an axe, then maybe using parts of the body for measures are usefull. Not the first furniture I made, also working in metal. Also in mathematic and physic the metric system is way better (Even NASA now uses the metric system since 2 probes crashed on Marte due to calculation errors in the imperial system)
Just wait for an American to tell you how it's easier to use fractions with imperial. I've legit seen them say shit like 3/8 of an inch is easier to think about than 9.5mm.
Woodworker in US here, and I prefer metric. Also consider the thickness of plywood is actually in metric now - "3/4" is actually 18 mm but they have to market it as 23/32.
I've chosen to join the other 8 billion people on earth.
Are you telling us that you are actually making, say a box, by measuring it with your hands and feet? That’s barbaric!
I’m guessing you actually use a tape measure like the rest of us.
Woodworking, sure. You have a piece of wood 2' 5 5/8“ long that you need to cut into quarters. Can you calculate that in your head? Metric is SOOOO much easier.
I like imperial for big things. like you said it's easier. For small things like 3d printing and such I prefer metric (basically anything with increments smaller than 1/16"). It just depends on what scale you need to work on.
There are (huge) costs to retooling production to move from imperial to metric. Even if a company wanted to make that move they'd have to transition in phases and will likely end up with additional equipment to maintain. There's also significant training for workers (who will likely commit errors in the beginning) which will impact production. And what happens to the old equipment? I'd guess a significant portion of that would end up getting scrapped and landfilled.
Perhaps I'm biased, but sometimes it's easier to work in fractions. Also, setting room temp is objectively better in F. I can tell the difference between 74 and 75. That said, I'm also a scientist so I'm permitted these opinions.