Why is it that nobody talks about imperial threads anymore? These threads were the standard that everyone went by. It does have a ring about it to name British Armstrong, Whitworth,British Standard Fine and not to mention CEI or BSC. It was quite clear that Whitworth was used as blind threads in alloy and BSF in steel. The CEI/BSC thread was unique in having 26 tpi. irrespective of diameter. Then some smart alec decided that threads should be "unified"..UNF and UNC! I mean what spanner in "unified" could fit the same nut as 1/4" and 3/16" BSF and Whit. In my nut assortment in the shed, I still have cadmium plated, (illegal plate)cycle thread nuts and bolts! Come on Chaps, lets hear it from the old school!!