Imperial Measurements Explained

[Lionelgee]

Hello All,

As I was only ever taught Metric measurements at school all the Imperial stuff found in Series Land Rovers are all a bit different to me.

I found this really good site which explains Whitworth AF and the like in spanners, bolts and threads amongst other things .... Accessed 17th October from, Imperial to metric socket and spanner size comparison charts. (http://www.baconsdozen.co.uk/tools/conversion%20charts.htm).

The following page also explains some of the history of different sizes - you need to scroll down to come to the definitions http://www.baconsdozen.co.uk/index.htm

Now all I have to do is hope that it is all good information and that people don't post up a flurry of corrections :)

Kind Regards
Lionel

[JDNSW]

Hello All,
........

Now all I have to do is hope that it is all good information and that people don't post up a flurry of corrections :)

Kind Regards
Lionel

Only real corrections I could spot was the table for wheel nut sizes - Series Landrovers changed the spanner size 1n about 1970, not 1972 (but not a sudden change!), and the earlier size is not 15/16" or 24mm, - it is 9/16" BSF (although the others will work).

Additional information - BA, although a very old and effectively obsolete thread, it is actually a metric thread, but with a narrower thread angle.

Whitworth is the oldest thread standard, and in most sizes UNC has the same threads per inch although interchanging the two is poor practice as the thread form is slightly different.

Although you are unlikely to come across them, in the nineteen twenties, thirties and even later, some popular engines used metric (French, not ISO) with Whitworth bolt heads and nuts. These were used on the DH Gypsy series aeroplane engines and on Morris car engines from 1919 into the thirties.

John

[87County]

Not meaning to be pedantic either :), but there's a misprint in the lower conversion list where .512" is shown as 11mm - obviously should be 13mm.