a customer gave me some witworth wrenches and sockets. i don't understand the measurements. wrenches marked 7/16 that are bigger than 3/4" . what are they measuring?
https://en.m.wikipedia.org/wiki/British_Standard_Whitworth Sent from my iPhone using The H.A.M.B. mobile app
Well I believe that is an English system of measuring so you might want to ask Uncle Google if he knows anything about them. You could buy a LBC and have fun as well.
Short answer - number on the Whitworth wrench [or socket] corresponds to a bolt diameter not the bolt head or nut size. All goes back to the late 1800's, many subtle changes over the years due to various factors. Ed
Hey TB33, Those Whitworth Tools came standard with our Greeves Motorcycle that was made in England. The bikes made us buy another complete set of tools. We already had the USA tools and a set of metric tools, now another set? They were just a little off of the measurements of the other tools. Jnaki Sometimes if not marked and they were sitting near the other tools, you thought whatever you picked up fit and after a short time, it did not. Whitworth is an old British standard for screw threads and sizes. You need the Whitworth size tools to work on your old Austin, Rolls-Royce, Jaguar, MG, BSA or other old British made automobile or motorcycle.
I'll take em, just kidding. It's true the wrench size is the diameter of the bolt. What you might not know, is early American tools used the Whitworth system for a while. Are they for sale???
i should have realized it would be an over simplified reasoning for the marks. 3/8 bolt= 3/8 wrench/socket. makes sense now. i was thinking elevator when it was just a lift.........
not for sale. i have been working on more and more early british stuff. i have collected a good selection of hardware and now i have the proper spanners....
Yes, the pitch of the threads were different too. I had a bunch of those wrenches and socket sets years ago, all shinny and chrome from Snap-On. I put them on ebay a few years ago and got an OBSCENE amount of money bid for them. As expensive as they were when I bought them they sold for much, much more. I bought them in the early 70's when I rode Nortons and drove a Morgan. I suppose they went to another person who was as anal as I was.
thanks, interesting that the info said some used witworth head size but metric threads. that could drive us nuts over here.
Well theres British Standard Whitworth or BSW, British Standard Pipe or BSP, Unified Coarse or UNF, Unified Fine or UNF, SAE or AF.......and then theres Metric but as I ask people..........what are those things at the end of your legs?, metres or feet? ..............they are feet and the various Imperial systems for me...........lol...........btw some BSW and UNC sizes use the same thread count but differ in thread pitch ..........any metric bolts or nuts found in my garage are immediately thrown in the garbage bin lest they pollute the pure Imperial fasteners given a safe and warm home............lol.........andyd
Well when the monarch/ruler died a new one would take his place and came with a new set of feet so the measure had to be altered. Eventually standardized as the Imperial System. But based on 12" to 1 yard and on and on. I grew up with that system but Canada officially changed, somewhat, to the metric system or System Internationale many moons ago. My students kind of know both so we have two official languages as well as one and a half, 1.5, systems of measure. I still think in Imperial but I have to say conversion is way easier with a system based on ten. Heck the whole world with one exception (other than scientific endeavours)uses it. I have some of the Whitworth on my TR6 and at times I'm at my wits end to find replacements!
Whitworth spanners make excellent wind chimes , I have one I made from all new whitworth stuff a coupla years ago ,other uses are unknown to me .....
Andydodge, I do exactly the opposite. Turf any Imperial nut or bolt so they don't get mixed up with my Metric fasteners. I gave away a good selection of Whitworth spanners to a gent who owned an old Rolls Royce as I had no use for them.
LOL...........like I said........what are those things at the end of your legs?................I'll save up any metric stuff I find for you...........lol...............Andy Douglas
I've got two sets of Whitworth and British Standard for use on the Merlin... Cost a lot years ago, but would hate to think what it would cost me now.
I forget the details but Pre War MG used Witworth heads and metric threads or something like that due to a good deal they got on used screw machines. You need to be real careful replacing hardware. Bob
If only it were that simple..... There are also: BA threads (British Association -used on Lucas electrics) , BSCy (British Standard Cycle -used on a lot of Brit motorcycles), BSB, (British Standard Brass-that's that weird thread used on old Lucas headlights) BSP has two versions, BSPP and BSPT. Then of course there's UNS, UNEF, NPT, NPS, NPSF for working on one of my old Chevys. Basically, although I have more than a thousand taps and dies representing all the threads listed above in my workshop, it will be pretty much a racing certainty that I won't have the particular tap or die that I need to clean up a thread on whatever the job is that I'm doing right now.
Hello, Our set of Whitworth tools went with both of our two Greeves Motocross/Scrambler bikes we sold in the first stage, 1964. But, when I bought my second Greeves Motocross bike in 1966, another small set of Whitworth tools came in a neat compartment attached to the bike. That was super handy when repairs were necessary out in the 100 mile desert races. It also held a couple of new sparkplugs for my two plug head. The 66 motocross bike had an extended swing arm for traction, too. Jnaki Once that portion of our desert racing era was over, all of the Whitworth tools went to the new owner of the 66 Greeves Motocross bike. Now, my garage was back to the standard USA and over in another tool box, the evil metric tools.
I am probably mistaken but as I recall whitworth wrenches stated the bolt shank measurement and not the head. I have some whitworth wrenches in my stuff from my old Limey bike days. Unless you just happen to be good at matching wrench size by looking at the opening or are working on Brit stuff they are just good conversation pieces. I would keep them use them when I needed too and be the kewl kid o the block.
Whitworth thread angle is 55 instead of 60 like Metric and Imperial, so even once each decade, when the Imperial/Whitworth pitch(threads per inch) is the same, things still likely will jam up. The nicely radiused roots of Whitworth threads were quite cool. I think the late great Carroll Smith may have said something like, "we had the perfect thread design available at one time. But we abandoned it " referring to Whitworth.
had a MG that had them , needless it had rounded head bolts when I got it , and got pretty good at using a fitsall wrench repairing it . when I restored it , I spent a small fortune on finding the bolts and nuts and a tool set from the Triumph dealer as he was the only place I could get a proper set , ( which I sold with the car , the guy who bought it had to have them when he found out I had a set ) was almost tempted on retapping the whole thing to SAE, since I replaced the prince of darknesses stuff already with the tinkerer from Daytons stuff .. ( still think lucas used the fog and moisture of the U.K. as part of the electrical systems )
i really appreciate all the responses. i had asked this same question to my friend "Dave the Brit" who is from that side of the pond, talks funny, uses odd expressions drives a series III 109 and plays "football" with a round ball [WTF?] and he replied "not a clue mate"
English Whitworth and BSF (British Standard Fine) were developed in the 19th century independent of the rest of the world, in fact that was the time when various countries were developing their own standards. As others have pointed out, wrench sizes refer to the bolt size (3/8 wrench for a 3/8 bolt) not the head size. The other difference seems to be, Americans made the bolt head a certain size and the wrench a hair bigger so it would fit over the head. The Brits made the wrench a certain size and the bolt head a hair smaller. So, American wrenches fit loose on Brit bolts and Brit wrenches won't go on American bolts.
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