Why are SAE sockets formatted in fractions?

[Rmay635703]

Why ? Those are socket / wrench sizes. Outside of the US (and Canada), how common do you think SAE tools are ?

Many metric wrench, socket, nut and bolt sizes are extremely rare outside the US also.

It’s unfortunate that metric fasteners don’t have a single universal wrench and socket size for the head of the bolt/nut). Sadly metric hardware has close to a dozen Different Non-interchangeable standards as compared to 1x standard for sae wrench/socket size for all hardware.

At work the same size nut and bolt might require 3x wrenches and 2x drive sockets depending on the brand of fastener and country of origin.

Good design practices eh?

Why ? Those are socket / wrench sizes. Outside of the US (and Canada), how common do you think SAE tools are ?

SAE=Imperial if your in England you will still encounter Imperial parts, even on supposedly completely metric equipment .

That’s why a lot of old mechanics in all parts of the world remember that certain wrench sizes (in metric ) fit certain imperial sizes “good enough “

Certain metric sizes are extremely uncommon
more uncommon than English unit fasteners because the Euro zone manufacturers skip certain sizes altogether when making vehicles and heavy equipment.
Then those wrenches and sockets are not commonly in sets.
Other parts of the world will use the sizes Europe skipped resulting in the exact same issue as no sets contain certain size sockets/wrenches when you are in Germany for example.

 

[ZeeOSix]

Why ? Those are socket / wrench sizes. Outside of the US (and Canada), how common do you think SAE tools are ?

Why what? I posted what the common fractions used are. Doesn't matter if SAE tools are common or not. Those common fractions apply to scales too, like posted below.

 

[ZeeOSix]

I consider any fractions down to 16ths of an inch common, 32nds and beyond not so much. This is my personal opinion only, likely based on my ye olde SAE sockets and wrenches.

All the tape measures I have have a 1/32 resolution. Mechanics/machinist scale goes down to 1/64th.

 

[Rmay635703]

Why what? I posted what the common fractions used are. Doesn't matter if SAE tools are common or not.

No offense but fractions are grade school stuff.

In metric countries I have seen fractions next to a kilo for food measurements (instead of the grams measurement.

Like half a Kilo

The argument presented here reads like a millennial didn’t finish grade 8 and needs a calculator problem I see all over because of lazyness (yes I used to be considered a millennial, now I’m an Oregon Trail era kid supposedly)
Not sure why (to quote another closed thread) my generation behaves like r-word s

I had to learn this in 2nd grade, it’s not hard, you need a wrench of a particular size you grab it.

Now explain screw gage and penny scales, those actually are rather stupid even if there is a definition for them.

 

[ZeeOSix]

The argument presented here reads like a millennial didn’t finish grade 8 and needs a calculator problem I see all over because of lazyness ...

Probably same ones that can't read an anolog clock either.

 

[ZeeOSix]

Deleted - double post.

 

[CheezWhiz]

related question- why is the denominator always a power of two? what happens if i run into a 2/3 inch hex nut? i'm HOSED, that's what!!!

 

[Rmay635703]

related question- why is the denominator always a power of two? what happens if i run into a 2/3 inch hex nut? i'm HOSED, that's what!!!

Nothing weird like that exists.

That’s why unlike metric fasteners the
SAE follows one standard for each stud size

 

[CheezWhiz]

Nothing weird like that exists.

That’s why unlike metric fasteners the
SAE follows one standard for each stud size

It's 3/7 inch thread, 15 threads per inch. I also need a tap and die to clean the threads up. PLEASE ADVISE.

 

[DuckRyder]

related question- why is the denominator always a power of two? what happens if i run into a 2/3 inch hex nut? i'm HOSED, that's what!!!

 

[kschachn]

Here it is. It was the British who came up with the system during the industrial revolution. The system is based on the concept of one half.

Start with one. One half of that is simply 1/2. One half of that is 1/4. One half of that is 1/8. One half of that is 1/16. One half of that is 1/32. One half of that is 1/64.

Then it was just a matter of filling the gaps with 1/32, 2/32, 3/32,4/32 etc.

Yes. And related to my comment about the use of dividers and measuring strings.

 

[paulo57509]

What used to be a gotcha for me regarding metric fasteners and wrench sizes is the two standards used, ISO and JIS.

Example: M8 fasteners. ISO M8 have 13mm heads; JIS M8 have 12mm heads. Both are used on Asian imports. It got easier when I figured out that certain manufacturers use ISO (odd numbered), others use JIS (even numbered).

The GM mixed bag (the Camaro, SAE & metric falls into this category) is another *book of worms altogether.

*Book Of Worms - Bob Lais, circa 1990

 

[Rmay635703]

What used to be a gotcha for me regarding metric fasteners and wrench sizes is the two standards used, ISO and JIS.

Example: M8 fasteners. ISO M8 have 13mm heads; JIS M8 have 12mm heads. Both are used on Asian imports. It got easier when I figured out that certain manufacturers use ISO (odd numbered), others use JIS (even numbered).

The GM mixed bag (the Camaro, SAE & metric falls into this category) is another *book of worms altogether.

*Book Of Worms - Bob Lais, circa 1990

And if you have a nut and a bolt they usually aren’t the same size

And there are 6 different Euro metric standards each of which can require different size wrenches for the nut and bolt head

Look at the chart, pathetic situation try to use metric

The Right Way, The Wrong Way and The American Way | The Metric Maven

themetricmaven.com

The only wrench socket and hammer you will ever need

 

[Hall]

Why what? I posted what the common fractions used are. Doesn't matter if SAE tools are common or not. Those common fractions apply to scales too, like posted below.

You think scales in France or China or other countries that use the metric system use (imperial) fractions ? I work with chemists, technical people, etc based in Europe and they often try to provide US-based measurements and I always tell them "let me do the conversions". I don't expect them to know these values either. One person Europe that's here in the US tries to put conversions like this on tech docs:

Use 500ml (16.907 ounces) of chemical...

I'll "correct" it to (17) and they'll insist that it's "wrong". I remind them that no one will measure 0.907 add'l ounces and move on.

 

[ZeeOSix]

You think scales in France or China or other countries that use the metric system use (imperial) fractions ?

What's that got to do with the original question (post 97)? You asked a specific question, you got a specific answer, but now it's going off down some unrelated tangent rabbit hole. Who cares if countries that use the metric system understand fractions or not. Any human on earth should be able to understand fractions in general, regardless of what the context.

 

[ZeeOSix]

One person Europe that's here in the US tries to put conversions like this on tech docs:

Use 500ml (16.907 ounces) of chemical...

I'll "correct" it to (17) and they'll insist that it's "wrong". I remind them that no one will measure 0.907 add'l ounces and move on

I can easily measure an ounce down to a 0.1 ounce. If you can, then why not. Rounding 16.9 to 17.0 might not be good thing depending on what's being done, like mixing chemicals where the ratio is critical.

 

[supton]

I can easily measure an ounce down to a 0.1 ounce. If you can, then why not. Rounding 16.9 to 17.0 might not be good thing depending on what's being done, like mixing chemicals where the ratio is critical.

If it matters, shouldn’t the give the range allowed? +/-1%, +/-5ml, etc.

 

[Opelman]

WRT SAE vs metric, I find it interesting that the world has no choice when it comes to ratchet and breaker bar drive sizes. It's either 1/4", 3/8", 1/2", 3/4", etc.

Which also reminds me I need to post a picture of a 3/4" drive Craftsman ratchet I saw in my FIL's toolbox the other day. He's a retired owner/operator OTR trucker and has a set of BIG TOOLS.

Don't forget the ww2 Snap On 9/32 drive stuff. Biggest I used regularly was a 1" drive impact for bus lug nuts.

 

[Opelman]

Nothing weird like that exists.

That’s why unlike metric fasteners the
SAE follows one standard for each stud size

Except for 7/16 hardware.

 

[D60]

Except for 7/16 hardware.

9/16" also but 9/16" is kind of considered a "specialty" or "automotive" size and sometimes only at true fastener houses -- although I've seen it in Hillman stuff at my Ace Hardware. Many smaller "hardware" stores jump 1/2" to 5/8"