In the beginning, and off the top of my head as I remember it ...
Each machinist was his own toolmaker. First you had to make or get your lathe. Then you made your taps. Having a tap you made a die. Now you could make a nut and bolt. There was no standardization of the screw threads, either in pitch, diameter or profile. Dimensions were as the machinist saw fit. If something broke the best bet was to take it back to the machinist who made it.
Some machinists were more successful than others. This meant it was another machinists time or money to obtain a duplicate set of taps and dies for manufacture of nuts and bolts. This led to a number of different standards.
Now I turn to my trusty 1909 Britannica. In 1841 Sir Joseph Whitworth proposed the adoption of a uniform set of screw threads that caught on very well in England.
With continuing standardization most of the individual based standards died out. Whitworth threads were gradually replaced by standard inch and metric systems but Whitworth persisted into the 70s at least. I would say Whitworth was in solid decline after WWII as tooling wore out.
Joe Bender-Zanoni
At 01:06 PM 6/22/01 -0400, Moos, Jerry wrote:
>Will someone please explain Whitworth to me? I've heard of it for years,
>but I've never understood what it meant. Some old TA cranks were marked
>"W", which I was told stood for Whitworth, but in reality all that meant was
>that they had English pedal thread. So what's the difference between
>Whitworth and ordinary English thread?
>
>Regards,
>
>Jerry Moos
>
>-----Original Message-----
>From: Wdgadd@aol.com [mailto:Wdgadd@aol.com]
>Sent: Thursday, June 21, 2001 9:53 PM
>To: mpetry@bainbridgeisland.net; lenoremeyer@hotmail.com;
>Classicrendezvous@bikelist.org
>Subject: Re: [CR]Witworth tools for British Bikes
>
>
> Most suppliers of British motorcycle spares stock reasonably priced
>Whitworth socket sets and combination wrenches, usually of asian
>manufacture.
>Maybe try Moore's Cycle Supply, West Hartford,Ct.(has website), British
>Marketing,Laguna Niguel,CA, or Fair Spares America, San Jose, CA. I have a
>set of Koken sockets I've used for years; not pro quality perhaps, but fine
>for hobbyist use.
>
>Regards,
>Wes Gadd