The Apollo Lunar Module Guidance computer was done in metric just had imperial displays since that is standard in aviation.
Why are SAE sockets formatted in fractions?
- Thread starter Crash Bandicoot
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The quick answer is there is no such thing as SAE sockets or measuring system.
There are "SAE" sockets and wrenches. They are based on the English/Imperial measurement system.
United States customary units - Wikipedia
What Is the Difference Between SAE & Metric Sockets? | Hunker
While the majority of bolt-type fasteners used in the United States conform to one or the other measurement scale, the difference between SAE and metric fasteners (and their corresponding sockets) is as profound as the difference between yards and meters: They are almost the same, but not quite.
Metric Policy
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i would say that if a numeric system based on the inch, ( .500 for 1/2" for example) was used, it would be easy for the sizes to get mixed up.
the difference in the systems make then easily distinguishable from each other.
metric based bolts are torque based, mean all 10mm bolts are supposed ro be torqued to X and 14mm and to be torqued to X. At least rhat is how i understand it, explained to me by a pump engineer. No specs need per unit, if it is size Y it get torqued to X value.
the difference in the systems make then easily distinguishable from each other.
metric based bolts are torque based, mean all 10mm bolts are supposed ro be torqued to X and 14mm and to be torqued to X. At least rhat is how i understand it, explained to me by a pump engineer. No specs need per unit, if it is size Y it get torqued to X value.
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This literally happened. The public didn't understand that 1/3 is bigger than 1/4, because 4 is bigger than 3. This was in the 70s or 80s, too. So our educational system has been failing the masses for decades. Lol
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Really? How did I never notice that? Lol. Been using clippers for 20+ years and never figured that out. Haha
If someone can't realize that a 1/2 inch socket is bigger than a 1/4 inch socket, then something is really wrong, lol.
Torque specs are way more complicated than that, regardless if the fastener is SAE or metric.
Plus it's really about the designed clamping force.
A fastener spec is not the system of measurement.There are "SAE" sockets and wrenches. They are based on the English/Imperial measurement system.
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United States customary units - Wikipedia
en.wikipedia.org
What Is the Difference Between SAE & Metric Sockets? | Hunker
While the majority of bolt-type fasteners used in the United States conform to one or the other measurement scale, the difference between SAE and metric fasteners (and their corresponding sockets) is as profound as the difference between yards and meters: They are almost the same, but not quite.www.hunker.com
Rather than calling them SAE, calling them english fractional would be much closer to the proper name.
There are also Metric SAE bolts as well. See the link below.
The term SAE for fractional sizes came from the normal automotive bench racers that seem to like inventing certain automotive terminology's. I suppose its the same ones that reinvent some of the automotive nomenclature as well. Including the spelling of the terms.
Like the new term for BRAKES on a vehicle are now, BREAKS.
J2295M_200606: Fasteners - Part Standard - Cap Screws, Hex Bolts, and Hex Nuts (Metric) - SAE International
This SAE Part Standard covers selected metric screws, hex bolts, and nuts manufactured in accordance with American Society for Testing and Materials (ASTM) and SAE fastener standards. This document covers fastener materials often used in ship systems and equipment but its use may be applied wherever
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I didn't say or claim they were. Said the SAE standard was based on the English/Imperial measurement system.
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If you read the links I posted, it was SAE who came up with the fastener standards (which in turn needed the matching tools), not "bench racers".
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Industry terms/nomenclature and bad spelling/grammar are completely separate topics.
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Well, that is how it was explained to me. I understand what you are getting at, but max torque value is commensurate to size of bolt, so it makes sense. This was from an engineer of a German pump company that I know. That is how they relay proper torque values to tech in the field, say in Saudi Arabia.
Would anything ever have a torque spec of 100ft lbs with a 10mm bolt, likely not.
It is difficult to explain, but I do agree that there is more to it.
That's just one factor, and yes obviously larger diameter thread fasteners can take more torque in general. But just the material the fastener is made of (ie, fasterner "grade") for the same exact sized fastener can drastically change the torque value. Thread pitch, dry or lubricated threads, application, etc ... some other factors involved. Look up torque specs for fasteners that include the size, grade, thread pitch, dry or lubed threads, and you can see how all those factors effect the torque spec.
Yes standards, NOT THE MEASUREMENTS stamped on a wrench. Using the term SAE to describe a size of an opening in a wrench is from the years of bench racers or ones sitting on a bench drinking a beer trying to figure out how to differentiate a metric measured tool from a tool that uses fractions of an inch to describe its opening. Never in the mid 50's was the SAE term used to describe an open box end wrench or sockets size capability.
It applies here, same passed on nonlogic. What really hurts is when so called professional writers or outfits use the incorrect nomenclature.
Basically the measurement of the distance across the flats on bolt heads IS stamped on the wrench/socket. What do you think a wrench or socket stamped with "1/2" means? What do you think a wrench or socket with "12 mm" stamped on it means?
There were fractional fasteners way before there were "bench racers" trying to figure out what size a fastener was or what tool to use on them. SAE had a major role in standardizing fasteners for the automotive industry. Ever since there were fasteners produced in fractional inch dimensions, there were also tools to match those fasteners.
Note in the article linked below that SAE was used over 100 years ago. It was even sometimes stamped right on wrenches. "Bench racers" did not invent the term SAE wrench or SAE socket. SAE did, and "bench racers" simply used the terminology.
The evolution of standard wrench sizes
progress-is-fine.blogspot.com
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The guy and his team mostly responsible for the development of the US space program, the early rockets through the Saturn V heavy launch vehicle were not Americans and grew up on the metric system. So there is that. LOL
To go back to your given examples, "SAE" is a common term to refer to fractional hardware and tools.
Nobody is selling "break pads" by that spelling. It's not an accepted term, no matter how many dopes have used the wrong word.
