On 4/7/23 19:22, Emanuel Berg wrote:
The British o-ring standard BS was based on inch measurements. It was then adapted so all measurements are in mm to precision 0.1 mmmick.crane wrote:Or is "metric" one of these things spared by the Brexit Bonfire?It depends which gear your camp is since the metric system is partly implemented and partly co-existsBritish Standard Pipe still in use for plumbing and 1/4", 3/8" of specification I forget for camera mounts.Boxing gloves, drums ...
This standard is now adopted in the US by the SAE.So if you buy an o-ring in the US you will get a metric precision ring certified by the SAE who derive it from the British BS measurement which itself is metric, which in turn is derived from nominal inch measurements e.g. 3/32"