Odd Socket Sizes?

[YoshiMoshi3]

• I x/32 " socket sizes are a bit "odd" that many people don't know about.
• Whitworth socket sizes 1/16 W, 3/32 W, 1/8 W, 3/16 W, 1/4 W, 5/16 W, 3/8 W, 7/16 W, 1/2 W, 9/16 W, 5/8 W, 11/16 W, 3/4 W, 13/16 W
  • 5/32 W is rare, AF dimension is unknown
• I know that there are BA socket sizes, 8 BA, 7 BA, 6 BA, 5 BA, 4 BA, 3 BA, 2 BA, 1 BA, 0 BA
  • Smaller AF sizes exist, for example 9 BA, 10 BA, little practical use
• A 57/64 " 12 point chrome deep socket that was made by Herbrand, Wright, and Firestone
• A 53/64 " 12 point chrome deep socket that was made by Duro-Indestro
• 6 point shallow sockets by Astro Tools 783111, 9.5 mm, 10.5 mm, 11.5 mm, 12.5 mm, 13.5 mm, 14.5 mm, 15.5 mm, 16.5, 17.5 mm, 18.5 mm, 19.5 mm
• 41/64 ", 45/64 " impact deep spline sockets, external hex drive (various manufacturers, Steelmen 78539 and 78540 are an example)
• 13/64 ", 15/64 ", ignition combination wrenches can be found in most ignition wrench sets
• 21.5 mm and 22.5 mm swollen lug nut sockets
• 20.6 mm spark plug socket (typically double marked with 13/16 " as well, likely manufactured to 13/16 " over 20.6 mm)
• 6.3 mm socket (typically double marked with 1/4 " as well, likely manufactured to 1/4 " over 6.3 mm)

Are there other sizes that I don't know about? Please post here.

 

[KnurledNut]

20.6mm spark plug socket
And those 6.3mm SK sockets

 

[humber2]

Add 9 and 10BA to the list.

I deduced those larger /64 sizes were within tolerance for Whitworth jaw sizes.

without mentioning whitworth they have a seamless inclusion into sets.

YMMV

 

[Kscardsfan]

I have a 29/32 and 31/32 socket for no better reason than I can.

 

[wantedabiggergarage]

One of my sets came with a 4.5mm socket.

 

[dscheidt]

Add 9 and 10BA to the list.

I deduced those larger /64 sizes were within tolerance for Whitworth jaw sizes.

without mentioning whitworth they have a seamless inclusion into sets.

YMMV

the 32nd sizes were the USS heavy nut series, which came in at the end of the 19th century and was largely obsolete by WWII. Production rationalization during the war killed the rest of it, except for a few outliers (19/32 shows up in electrical stuff still.) Ford used 25/32 on front suspensions until the early 70s.

No doubt people use these on metric and BS bolts, but they had a real use.

 

[Dave455]

The smallest Whitworth size, found as a hex nut, is 1/8, and those are rare.

BA sizes extend from 0 to 16, 0 being biggest, 16 being smallest. In practice the smaller sizes (smaller than say 10BA) are only found in very specialist applications (such as instrument manufacture) and the even numbered sizes are preferred. The smaller sizes tend to exist as screws only, so you will seldom find nuts.

If you think of BA as being the British equivalent of the Unified “numbered” series, you are not far wrong.

 

[cvairwerks]

Still use 3/32, 5/32, 7/32, 9/32 and 11/32" sockets on occasion. Generally when working with electronics or connectors and their mounting brackets.

 

[ecotec]

One of my sets came with a 4.5mm socket.

All of my 1/4” sets have a 4.5mm.

 

[vwpieces]

 

[cherrybomb]

I have a 29/32 and 31/32 socket for no better reason than I can.

Many real old SK 1/2 drive socket sets had these

 

[ecotec]

I have those, but I haven’t used them yet. It remains to be seen whether I will ever use them…

I have flip sockets with 1/2 sizes for swollen lug nuts.

 

[YoshiMoshi3]

20.6mm spark plug socket
And those 6.3mm SK sockets

Interesting. It looks like some of those 13/16" spark plug sockets have "13/16" stamped onto them and some of them have "20.6" stamped onto them. I wonder if they are machined to 13/16" or 20.6 mm?

Interesting about the 6.3 mm sockets, thanks for pointing that one out. I'm wondering if it's actually machined to 6.3 mm or 1/4 " and just stamped with 6.3 on it.

Add 9 and 10BA to the list.

I deduced those larger /64 sizes were within tolerance for Whitworth jaw sizes.

without mentioning whitworth they have a seamless inclusion into sets.

YMMV

9 BA and 10 BA, dang those seem very small

A 57/64 " 12 point chrome deep socket that was made by Herbrand, Wright, and Firestone
A 53/64 " 12 point chrome deep socket that was made by Duro-Indestro

57/64 " = 22.621748 mm
53/64 " = 21.034248 mm
7/16 W = 20.83 mm
1/2 W = 23.37 mm

Which whitworth sizes are you referring to? I don't think any of them are close, but there may be some rare whitworth sizes that are uncommon and not widely known that I don't know of, like X/32 W and X/64 W sizes

One of my sets came with a 4.5mm socket.

Thank you! I forgot that some of the smaller sizes do come in 0.5 mm sizes.

I have those, but I haven’t used them yet. It remains to be seen whether I will ever use them…

I have flip sockets with 1/2 sizes for swollen lug nuts.

Forgot about swollen lug nut sockets. I guess there are some that are out of the astro half sizes. Such as 21.5 mm and 22.5 mm, which are common in swollen socket sets.

 

[Kscardsfan]

Many real old SK 1/2 drive socket sets had these

Had to fix your Model T and A Fords.

 

[Dave455]

Interesting. It looks like some of those 13/16" spark plug sockets have "13/16" stamped onto them and some of them have "20.6" stamped onto them. I wonder if they are machined to 13/16" or 20.6 mm?

Interesting about the 6.3 mm sockets, thanks for pointing that one out. I'm wondering if it's actually machined to 6.3 mm or 1/4 " and just stamped with 6.3 on it.



9 BA and 10 BA, dang those seem very small

A 57/64 " 12 point chrome deep socket that was made by Herbrand, Wright, and Firestone
A 53/64 " 12 point chrome deep socket that was made by Duro-Indestro

57/64 " = 22.621748 mm
53/64 " = 21.034248 mm
7/16 W = 20.83 mm
1/2 W = 23.37 mm

Which whitworth sizes are you referring to? I don't think any of them are close, but there may be some rare whitworth sizes that are uncommon and not widely known that I don't know of, like X/32 W and X/64 W sizes



Thank you! I forgot that some of the smaller sizes do come in 0.5 mm sizes.


Forgot about swollen lug nut sockets. I guess there are some that are out of the astro half sizes. Such as 21.5 mm and 22.5 mm, which are common in swollen socket sets.

Just to help you out on the Whitworth.

Whitworth (BSW) and BSF nuts and bolts are generally found from sizes 1/8 and upwards, and in 1/16 increments.

Some sockets are dual marked, because up till the war, BSF nuts were one size smaller. After the war, both used the smaller size.

You will sometimes find 1/32 increments, but they are only usually found in smaller sizes, and are less common.

You have to remember that in the smaller sizes, the BSW / BSF sizes overlap the BA sizes, so a BA would normally be preferred. The only reason for using a BSW size, is if you are putting a screw into cast iron, where the coarser thread is better suited.

For this reason the /32 sizes are usually only found as screws, so no socket would be needed.

 

[Cruzan80]

I think I have a Husky 13/32 socket in 1/4"...

 

[Ohio Andy]

I purchased an SAE set of Wright Tools Wrenches and they did not include (and do not sell) 9/32" or 11/32 so I purchased Proto to fill the gap. They did not include 1-13/16 so I bought one.

I purchased a set of Wright Tools Metric Wrenches from 6mm to 32mm and neither Wright Tools nor Proto seem to sell a 31mm and I had a spot for one so I bought a Tekton even though I have never needed one and probably will never need one, but I was placing an order and I got tired of seeing this hole there and I am not likely to use it since I no longer work on any agricultural machines (I am long off the farm).

When I have an empty spot (these are in a tool roll with labeled spots) it is easier to tell if I missed a tool and left it out if the roll is full. That policy saved me of a missed item Friday as I went looking around to figure out where my two missing items were sitting.

Clearly neither 9/32 nor 11/32 are odd ball, but I suppose that 31 mm might be since so few things use it. I think there is an axle nut on some odd-ball car that has one, but I could be wrong.

 

[Cruzan80]

I purchased a set of Wright Tools Metric Wrenches from 6mm to 31mm and neither Wright Tools nor Proto seem to sell a 31mm

Thinking there is a typo here. Otherwise hard to sell a set ending in a number they don't make. Guessing 6-32?

 

[Ohio Andy]

Thinking there is a typo here. Otherwise hard to sell a set ending in a number they don't make. Guessing 6-32?

You are correct, it is to 32 mm. I fixed it above. A nice set. The sets came in a nice "roll" that does not roll that well but I can easily adhere it to a wall. I puth the sets into a Tekton roll because the Tekton rolls are very nice and the rolls I purchased were very inexpensive. I was going to sew my own but I could probably not purchase the materials for what I paid and it would not have been as nice. The Tekton rolls had spots open that the Wright Tools did not. I did that with one of my Proto Ratcheting wrench sets because the roll was a bit abused... And the Tekton rolls had different colors to distinguish Metric from SAE and when I bring both rolls it is nice to be able to just grab the right one without peeking inside.

 

[Cruzan80]

All good. I have done that myself.
OTHERWISE...
Just think of the advertising that could be done! We have a 6-79mm set (though we only produce sockets up to 36mm in that drive size). Amazing bargain! Get 40+ sockets for free (though they are invisible)...

 

[51dueller]

My Canadian Tire Maximum 300 piece socket set came with 7/32, 9/32, 11/32 and 15/32 sockets in shallow and deep. 7/32 and 11/32 are common enough. Gearwrench likes putting 11/32 in their wrench sets so I have that size but it doesn't bother me that my Wright set doesn't have it. I have 7/32 and 9/32 in a cheap ignition wrench set. Can't say I've came across a 15/32 fastener.

 

[matthew]

My Canadian Tire Maximum 300 piece socket set came with 7/32, 9/32, 11/32 and 15/32 sockets in shallow and deep. 7/32 and 11/32 are common enough. Gearwrench likes putting 11/32 in their wrench sets so I have that size but it doesn't bother me that my Wright set doesn't have it. I have 7/32 and 9/32 in a cheap ignition wrench set. Can't say I've came across a 15/32 fastener.

Doesn’t make much sense, but maybe a way to keep people rounding off 12mm fasteners with a 1/2” wrench.

Although I probably would stick with my separate metric and inch storage, I have thought about putting things in true size order before (3/8”, 10mm, 11mm, 7/16”, 12mm, 1/2”, 13mm, etc)

 

[nadogail]

I was told, back when I was still a kid, that the 19/32 and 21/32 sizes were to work on Ford engines, that was a long time ago.

 

[Semi-hole mechanic]

I was told, back when I was still a kid, that the 19/32 and 21/32 sizes were to work on Ford engines, that was a long time ago.

25/32 was also an old Ford size. **/32 were also common on old IH farm equipment.

 

[drokihazan]

I have a 1/4” BA socket set from Laser and a mixed 1/4” and 3/8” BSW Whitworth set from King ****. I have King **** Whitworth wrenches too.
Another guy I know who also works on a lot of Land Rovers has a set of universal Whitworth from Koken. I’ve never needed those, but they’re pretty unique. Older Land Rovers are full of BA in the dash and instrument clusters, and Whitworth in the drivetrain. Pretty much any Land Rover built prior to the introduction of Salisbury axles has a drivetrain full of Whitworth.

In all honesty, I’ve only worked on two Series trucks ever, and both were helping a friend, not a shade tree job myself. I’ve used a few of my BSW and BA sockets but I could have gotten by with a Knipex pliers wrench or a close-enough Metric/SAE size in every situation.

 

[Dave455]

I have a 1/4” BA socket set from Laser and a mixed 1/4” and 3/8” BSW Whitworth set from King ****. I have King **** Whitworth wrenches too.
Another guy I know who also works on a lot of Land Rovers has a set of universal Whitworth from Koken. I’ve never needed those, but they’re pretty unique. Older Land Rovers are full of BA in the dash and instrument clusters, and Whitworth in the drivetrain. Pretty much any Land Rover built prior to the introduction of Salisbury axles has a drivetrain full of Whitworth.

In all honesty, I’ve only worked on two Series trucks ever, and both were helping a friend, not a shade tree job myself. I’ve used a few of my BSW and BA sockets but I could have gotten by with a Knipex pliers wrench or a close-enough Metric/SAE size in every situation.

BA stuff is needed all the time.

Even when the U.K. adopted Unified threads, we never adopted the numbered series, so BA continued until ISO metric. Still does in some industries.

The Whitworth universal sockets are most needed in the aerospace world. Britool used to offer them, and most aircraft engineers who need them have a set of those.

KoKen are the only manufacturer to offer new Whitworth Universal sockets, though of course many offer regular sockets.

The advantage of Whitworth is that you need relatively few sizes, Four or Five will cover most sizes found on a car.

 

[YoshiMoshi3]

Just to help you out on the Whitworth.

Whitworth (BSW) and BSF nuts and bolts are generally found from sizes 1/8 and upwards, and in 1/16 increments.

Some sockets are dual marked, because up till the war, BSF nuts were one size smaller. After the war, both used the smaller size.

You will sometimes find 1/32 increments, but they are only usually found in smaller sizes, and are less common.

You have to remember that in the smaller sizes, the BSW / BSF sizes overlap the BA sizes, so a BA would normally be preferred. The only reason for using a BSW size, is if you are putting a screw into cast iron, where the coarser thread is better suited.

For this reason the /32 sizes are usually only found as screws, so no socket would be needed.

So British Standard Whitworth (BSW, Whitworth, W) and British Standard Fine (BSF, BS) wrench have the same distance across the flats? The difference between W and BS is just thread pitch? There are no unique sizes between the two? While British Association (BA) wrenches have unique sizes across the flats.

The uncommon whitworth sizes are 5/32 W, are there other /32 whitworth sizes that are uncommon that I cannot find a across the flat (AF) dimension for anywhere.

I'm looking to fill the gaps in my socket collection. I'm missing lots of inch sockets. I have a
Kobalt 1/4 " square drive, chrome, 6 point, socket set that includes, 5/32 ", 7/32 ", 9/32 ", 11/32 "
Harbor Freight Pittsburgh 1/4 " square drive, chrome, 6 point, socket set that included a 15/32 "
Kobalt 3/8 " square drive, chrome, 6 point, socket set that included 9/32 ", 11/32 ", 15/32 "

So I'm missing 13/32 ", 17/32 ", 19/32 ", 21/32 ", 23/32 ", 25/32 ", 27/32 ". Don't think I really have much a use for anything larger. But can anyone recommend a 6 point socket set that includes most of the more uncommon X/32 " AF sockets?

I have also been looking into odd drive sizes, I doubt any of them have any practical use today. As none of them are smaller than 1/4 "
9/32 " M square drive
5/16 " M square drive (10/32 ")
7/16 " M hexagonal drive (14/32 ")
9/16 " M hexagonal drive (18/32 ")
5/8 " F/M square drive (10/16 ", 20/32 ")
11/16 " F/M square drive (22/32 ")
13/16 " M square drive (26/32 ")
7/8 " F/M square drive (14/16 ", 28/32 ")
1.25 " M square drive
1/5 " M square drive

 

[wantedabiggergarage]

I believe the 9/32" drive size, was a WWII thing to keep enemies from capturing/using tools to be able to fix their stuff. (wasn't interchangeable on ratchet size)

 

[esben57]

The Whitworth universal sockets are most needed in the aerospace world. Britool used to offer them, and most aircraft engineers who need them have a set of those.

KoKen are the only manufacturer to offer new Whitworth Universal sockets, though of course many offer regular sockets.

A while ago I found some of these Tipco sockets. 3/16W UW13, all engraved RR174.
Not sure if they have a specific task although RR appears often on Tipco.

 

[dscheidt]

So British Standard Whitworth (BSW, Whitworth, W) and British Standard Fine (BSF, BS) wrench have the same distance across the flats? The difference between W and BS is just thread pitch? There are no unique sizes between the two? While British Association (BA) wrenches have unique sizes across the flats.

Whitworth's original system used larger heads than were actually needed, and the fine thread system used a size smaller head, to keep torque down (smaller size = smaller wrench), to keep from pulling threads in castings. Since Whitworth decided to use goofy[1] AF dimensions, tools are labeled with the thread size of the fastener they're supposed to fit. It's common to see a wrench bear both a W and BS size.

BA threads are a thing only a Victorian Englishman could have thought off. It's a perfectly logical metric (metric!) thread system, with sensible steps on everything, that was converted into imperial measurements, rounding at every alternative.



[1] there's a reason for them, but they're still goofy, and could easily have been nudged to a nominal dimension.

 

[Dave455]

So British Standard Whitworth (BSW, Whitworth, W) and British Standard Fine (BSF, BS) wrench have the same distance across the flats? The difference between W and BS is just thread pitch? There are no unique sizes between the two? While British Association (BA) wrenches have unique sizes across the flats.

The uncommon whitworth sizes are 5/32 W, are there other /32 whitworth sizes that are uncommon that I cannot find a across the flat (AF) dimension for anywhere.

I'm looking to fill the gaps in my socket collection. I'm missing lots of inch sockets. I have a
Kobalt 1/4 " square drive, chrome, 6 point, socket set that includes, 5/32 ", 7/32 ", 9/32 ", 11/32 "
Harbor Freight Pittsburgh 1/4 " square drive, chrome, 6 point, socket set that included a 15/32 "
Kobalt 3/8 " square drive, chrome, 6 point, socket set that included 9/32 ", 11/32 ", 15/32 "

So I'm missing 13/32 ", 17/32 ", 19/32 ", 21/32 ", 23/32 ", 25/32 ", 27/32 ". Don't think I really have much a use for anything larger. But can anyone recommend a 6 point socket set that includes most of the more uncommon X/32 " AF sockets?

I have also been looking into odd drive sizes, I doubt any of them have any practical use today. As none of them are smaller than 1/4 "
9/32 " M square drive
5/16 " M square drive (10/32 ")
7/16 " M hexagonal drive (14/32 ")
9/16 " M hexagonal drive (18/32 ")
5/8 " F/M square drive (10/16 ", 20/32 ")
11/16 " F/M square drive (22/32 ")
13/16 " M square drive (26/32 ")
7/8 " F/M square drive (14/16 ", 28/32 ")
1.25 " M square drive
1/5 " M square drive

Essentially, yes! dscheidt above said most of it.

Originally, Whitworth (BSW) bolts had big bolt heads. Nothing goofy about the sizing, they measured twice the bolt size, measured across the corners of the hex.

When the later BSF threads were introduced, they realised that the BSW bolt heads were a bit big, so used the same standard sizes, but just one size smaller.

Later on, most industry switched to the smaller sizes for everything, so just use the “BS” size on the wrench or socket.

BSC (cycle) and BSP (pipe) threads use the same sizes too.

Sizes such as 5/32 BSW exist only as screws, so you will not find a socket of that size.

Yes, BSW and BSF differ only in the thread pitch. BSW are optimum for cast iron, BSF for steel.

BA threads are about the most logical ever invented. A 0BA measures 6mm (yes metric, even though they are specified in Imperial units) and each successive size measures 0.9 of the previous.

Every BA nut measures (across flats) 1.75 x the thread size, so they are unique sizes, but perfectly logical.

 

[esben57]

Essentially, yes! dscheidt above said most of it.

Originally, Whitworth (BSW) bolts had big bolt heads. Nothing goofy about the sizing, they measured twice the bolt size, measured across the corners of the hex.

When the later BSF threads were introduced, they realised that the BSW bolt heads were a bit big, so used the same standard sizes, but just one size smaller.

Later on, most industry switched to the smaller sizes for everything, so just use the “BS” size on the wrench or socket.

BSC (cycle) and BSP (pipe) threads use the same sizes too.

Sizes such as 5/32 BSW exist only as screws, so you will not find a socket of that size.

Yes, BSW and BSF differ only in the thread pitch. BSW are optimum for cast iron, BSF for steel.

BA threads are about the most logical ever invented. A 0BA measures 6mm (yes metric, even though they are specified in Imperial units) and each successive size measures 0.9 of the previous.

Every BA nut measures (across flats) 1.75 x the thread size, so they are unique sizes, but perfectly logical.

Essentially our Enigma code system. Had we been invaded, any attempt to repair/dismantle anything would have been thwarted due to sourcing correct spanner types.

 

[username2]

I've got some ReStore bought 9/32" Snap-on extensions I was saving as a Christmas gift for a friend of mine.

I think what I really need is a Whitworth socket to go with.

 

[YoshiMoshi3]

I've got some ReStore bought 9/32" Snap-on extensions I was saving as a Christmas gift for a friend of mine.

I think what I really need is a Whitworth socket to go with.

What is modern day application for 9/32"? Also do you have any of the sockets, if so would you be able to take an overall length measurement of a socket?

 

[NoahG]

I actually used my grandfathers 31/32” socket installing some hose bibs on rain barrels today.

 

[four.cycle]

What is modern day application for 9/32"?

electrical stuff
now and then I'll run into 9/32" on a really OLD mower. #6 machine screw.
and... if I'm building a Briggs, I will pin the throttle lever with a 6-32 machine screw and nut so the buyer can't screw with the idle speed.