Next time you strip a bolt blame the Americans, Japanese and French

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This concerns something as simple as a nut and bolt! Screw threads and screw drivers where originally developed as a fastener for suits of armour. In those days each blacksmith would probably have cut his own thread to his own specification. Then as things go, some kind of standard was desirable and here in Britain we developed the first and best standard for bolts in 1841 as well as standards for pipes and other threaded implementations. For bolts the two most common standards where British Standard Whitworth and British Standard Fine. Now these were treads having a wave form; imagine cutting the bolt down its length, the tread would appear like a sine wave. This is the strongest form for a thread however, Whitworth bolts sizes referred to the diameter of the bolt and this annoyed American mechanics used to their own much later standard, AF (Across Flats) which used a weak, straight cut thread form and in which the bolt size referred to the distance across the flats of the bolt head. An agreement between UK and US was the Unified Thread Standard, no doubt made by politicians rather than engineers this again used the weaker straight cut thread form (Actually a truncated thread form) Metric bolts also use this weaker form So, if you strip a nut or bolt easily when tightening it you know who to blame! Now, I am sure I will be inundated with replies to this one! - Not! all the best urban