PLEASE!!!
"Imperial" is The British Empire. Whitworth (the original standard), BA, many others.
"American" will "often" mean UTS, SAE for slang especially in transportation. Yes, even into England during WWII to take advantage of US/Can's MASSIVE screw-machine capacity. UTS/SAE are inspired by Whitworth but 'simplified' with 60 degree thread (ISO took this feature) (in fact "Metric" is SAE but rounded to French units).
I won't argue one for the other. You do want to know the systems: most SAE sizes can be Coarse or Fine thread. Our popular 1/4"-20 looks like a 1/4"-28. This seems like a headache (and is) but is necessary to keep machines together.
As for Gallons: The English Kings had approved MANY "gallons", all different. The revolting colonies had carried with them mostly just two buckets, and all common products used the Wine Gallon. (Showing what was important!)
"Foot" is not the King. The transition from Liz's petite feet to Chuck's big stompers would be traumatic. The Imperial length is the Yard. This has an inglorious history: this king, that queen, tax evasion, fire in 1834. Multiple copies were made and shared with US and Canada; on a later re-check, they did not quite match. Actually the French were Yards ahead of the English world in fine measuring. Fairly soon the US adopted an exact fraction of the French meter as our reference (2.54mm is 1 Inch exact).
1 inch = 25.4 mm, I am bilingual in Metric and BSW / BSF threads.
There is an automobile series here, UNC, different from Metric here, threads have different profile.
There is an automobile series here, UNC, different from Metric here, threads have different profile.
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I just wish bars would serve me a pint when I ask for one. None of this "12-oz pint" BS. A pint is 16 oz in the US and 20 oz in Canada where we use the imperial pint for some bizarre reason.
Tom
Tom
Canada is part of the British Empire?
So they use Imperial rather than American measures?
A pint is close to a half liter, that should be the standard.
Here we get large and small mugs, 500 and 350 ml, in places serving draught beer.
So they use Imperial rather than American measures?
A pint is close to a half liter, that should be the standard.
Here we get large and small mugs, 500 and 350 ml, in places serving draught beer.
As a Briton I see it differently. Most people are right-handed, so this dominant hand should do the most important task whilst gear changing - steering the car - whilst the less safety-critical action of changing gear can be done with the less dominant one.
On our narrow Devon roads I prefer driving my left hand drive 1974 VW panel van as I can tuck in closer to the hedges and I have become fully 'ambidextrous' in driving! Horses for courses, so to speak.
It wasn't always this way! I remember owning a ruler when at school with the conversion etched into it 1"=25.39mm. The inch was later redefined in metric units.
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One thing I can’t explain is the 5 meter tape measures I saw in Home Depot. They only have inches on the tape!
Those of us in Land Surveying here in the States might deal in “US Survey feet” (yes, there’s a difference), yards, chains, links, rods, poles, leagues, perches and Varas. These might be somewhat dependent on the location of our particular practice, but we’re required to have at least a passing knowledge of the more obscure units regardless. Failure to understand them in the context of a particular survey can lead to blowing the whole job, along with possibly serious financial and legal consequences.
To further complicate matters, in may states we’re required to tie in to the local or state coordinate systems - which are usually computed in SI units. It all sounds nuts, but after a while it becomes second nature.
To further complicate matters, in may states we’re required to tie in to the local or state coordinate systems - which are usually computed in SI units. It all sounds nuts, but after a while it becomes second nature.
Good news: the US Survey foot will be deprecated December 31 2022.
If they are clever they will switch to meters 😀.
That change was only made when things started to require more precision and both mm and mils were being used, often in the same industry. Electronics being one of them.
In the U.K. we often abbreviate mm as mill when speaking, which causes no end of confusion in the USA. When we are talking about mills (1/1000 of an inch), we call them thou 🤷🏻♀️
Those of us who grew up on the water might deal in fathoms and knots, but in reality, I only needed an RDF (Radio Direction Finder) and a "sounding rod" which was made from an old fishing rod with a piece of tape marking the boat's draw, the minimum depth before running aground. Fancy boats had a purpose built RDF which we didn't have, so I used a pocket transistor radio and turned it for the null. There were a few Florida AM radio stations that could be heard everywhere we went including the Bahamas, so it was pretty easy to pick 2 or 3 and find yourself on a nav chart within a few miles. WQAM Miami used to have its tower in the water near downtown Miami. 560 KHz requires a pretty tall tower, and its lights were visible for miles.
Navigation was by charts, and an RDF. A compass and a wind gauge on top of the mast offered some info for guessing the course offset in still water. Out in the Gulfstream, all bets are off as you will always drift North sometimes a lot. Speed was usually determined by the wind, so no accurate measurements were needed, or possible in the 60's and early 70's.
Navigation was by charts, and an RDF. A compass and a wind gauge on top of the mast offered some info for guessing the course offset in still water. Out in the Gulfstream, all bets are off as you will always drift North sometimes a lot. Speed was usually determined by the wind, so no accurate measurements were needed, or possible in the 60's and early 70's.
Short for mili inch. Even in the US, all the automotive related machine shops I ever went to called them thousandths or thou. Mill was what you did to a cylinder head to increase the compression ratio or fix minor warpage...IE, how many thou did you mill off my head?
I moved to Canada from the UK three years ago. Canada has lots of good points but its adherence to imperial in building products frustrates me. I can see the convenience of complying with our neighbour’s medieval standards but still.
One phenomenon I cannot explain is the Robertson screw head (square bit). It has to be the worst head I have ever used and yet it is by far the dominant type in hardware stores here. I have removed many from my house during reconstruction and I summarily send them to recycling to hopefully be turned into something of practical use. I can only assume it is a Canadian invention and has protected status or something. Canada is like this!
One phenomenon I cannot explain is the Robertson screw head (square bit). It has to be the worst head I have ever used and yet it is by far the dominant type in hardware stores here. I have removed many from my house during reconstruction and I summarily send them to recycling to hopefully be turned into something of practical use. I can only assume it is a Canadian invention and has protected status or something. Canada is like this!
That's a ECX screw...there are drivers made for them.
ECX Drivers https://www.amazon.com/ecx-screwdriver/s?k=ecx+screwdriver
Mike
Deprecation of the US Survey Foot has long-term implications, particularly in the reproduction of old “metes and bounds” surveys on large tracts. It will always be used, just not for new surveys like it once was. Oddly enough, it’ll cause further complications in the form of one more conversion that will have to be made. 😬