How were driver sizes decided?

[King Bojack]

How did the industry settle on a 1/4, 3/8, 1/2 size etc....? It's something that's always puzzled me. You'd figure each companies ratchets would only work with their sockets or something.

 

[matthew]

Don't really know the answer, but I have seen pictures of older stuff that's female drive, or hex drive, and various square drive sizes (9/32", 7/16", etc). I expect several ideas competed for a while, but between square being reasonably easy to produce with the technology of the time, and firms following multiple standards gradually thinning out, square drive simply evolved into the standard design. And as the number of units sold increased, companies just went with it, and the companies standardized on the drive sizes that proved popular.

 

[JSBriggs]

There used to be 1/8, 9/32, and 5/8 but those are now obsolete.

-Jeff

 

[wafrederick]

I have one Cornwell socket that is 5/8 drive.Plan on finding 5/8 square stock and welding on a cheap 1/2 drive socket with no warranty on that piece of 5/8 square stock.There is 1 1/2 and spline too.There is one socket no one picks up,13 5/8" and this one is used in power plants.Use a forklift to pick this socket up since it weighs a thousand pounds.

 

[billymade]

I think WW II brought about a unique widespread standardization movement; to streamline and simplify the war effort... through mass production. I can only assume that this had a effect on tools as well; allot of documentaries on WWII (e.g. history channel etc.a), talk about everything from fasteners to engines went under a big effort to be standardized (effort to reduce specialization but to use "standard" things in many different things being produced)... this way production and duplication was eliminated. I'm sure there is info somewhere about this change but my google skills at the moment aren't bringing anything up!

 

[joecon]

There are other drive 5/8 is used by some ind. so nobody walks off
with the tools also on here there was a thered about a 7/16 drive.
I have some 5/8 adp.

 

[MotoDave]

I've got a very old ratchet and socket set that are 1" hex drive Gotta get some pictures up on here some day.

 

[laz]

This is an interesting topic. There's usually incentive to not interoperate, and lock consumers into your brand. See the stupidity in the US cellphone industry, for example.

I like the WWII explanation... but it'd be nice to know if it's actually true.

 

[Gregg33]

I got some antique stuff (mostly pre WW2) and there are a myriad of drives, 2 or 3 different hex drives, an 11/16" female Mossberg ratchet and of course regular 1/4, 3/8, 1/2 and 3/4 drives. Interestingly, almost all of the old drive ratchets/ bars I have, have been modified or have special sockets so that they can be used with the newer more common drive sockets.

Of course we also all use 1/4 hex screwdriver bits and many of use have older screwdrivers or nut drivers with interchangable bits that are often round with 2 tabs/ tangs to lock it in place

 

[AZ_Catskinner]

There used to be 1/8, 9/32, and 5/8 but those are now obsolete.

-Jeff

Snapon still has 1/8" drive, just a limited selection.